OVERSEAS INVESTORS CHAMBER OF COMMERCE & INDUSTRIES … · The project of ‘Documentation and...

OVERSEAS INVESTORS CHAMBER OF COMMERCE & INDUSTRIES (OICCI), KARACHI

State of Conservation Report March 2013 – May 2013

Prepared and Submitted by

Heritage Cell – Department of Architecture and Planning, N.E.D. University of Engineering and Technology, Karachi

Team Members: Ar. Farida Abdul Ghaffar (Acting In-charge Heritage Cell)

Ar. Tania Ali Soomro (Project Architect) Ms. Anila Rahim (Cad-Technician)

Conservation Guidelines - OICCI

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TABLE OF CONTENTS

Introduction 3 The Site and its Location 3 Background of the Project and its Objectives 5 Documentation & Data Collection 6 Description of the Building OICCI 7 Present State of Conservation/ Maintenance 9 Architectural Features of Significance 10 Alterations/ Interventions / Additions 15 Identified Problems in Building Materials & their Causes of Decay & Damages 23 Proposed Remedial Measures and Conservation Interventions 31 Conclusion 34 APPENDICES Appendix I: Cleaning of Stone Surfaces 35 Appendix II: Lime Mortar Treatments 37 Appendix III: Polishing of Marble Surfaces 38


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INTRODUCTION ‘Oversea Investors Chamber of Commerce & Industries (OICCI)” is located in the historic hub of the city of Karachi in Serai Quarter. Serai Quarter is famous for its historic stone masonry construction. OICCI is a listed heritage property of Karachi, notified and protected under the Sindh Cultural Heritage Preservation Act 1994; bearing the enlistment number 1995-084 in the records of Department of Culture, Government of Sindh. The G+1 structure of OICCI Building, is constructed on plot no. SR-2/8. It is a single unit building, however two annexes were added to the main building block as extension some decades ago (exact years are not known). Altogether three blocks exist at the site. The main building block is centrally composed. Each block will be discussed in detail separately according to their present status in later part of this report. THE SITE AND ITS LOCATION The site can easily be accessed through all types of public as well as private vehicles because of its prime setting on one of the busiest arteries, i.e Talpur Road (Woods Street) and Shahrah-e-Liaqat (Frere Road). Both the roads allow one-way traffic. There is also a secondary road for two ways traffic named as Hasrat Mohani Road (Grant Road). The magnificent and historic I.I. Chundrigar Road (Mc-Loed Road) is perpendicular to the Talpur Road (Woods Street).Thus this building can also be accessed while approaching the Talpur Road (Woods Street) from I.I. Chundrigar Road (Mc-Loed Road). Most of the plots neighboring the OICCI structure offer commercial activities. Apart from the historic structures, other new buildings are constructed with Floor Area Ratio (FAR) as 1:3 for residential and 1:6 for commercial plots as per prevalent building bye-laws. OICCI building has an independent compound with private open spaces. Over the passage of time, the building has attained few alterations and extensions, which have affected its original glory. The building façade facing towards the road directly attracts dirt and pollution throughout the day. This is the reason the whole boundary wall of the building is covered with dirt and soiling and is in severe need of cleaning.


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OICCI Building

LEGEND

Main access to the Building

N


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BACKGROUND AND OBJECTIVE OF THE PROJECT The project of ‘Documentation and Conservation Guidelines for Overseas Investors Chamber of Commerce & Investors (OICCI)’ is commenced by its in-charge officer in response to the decay and damages that are presently faced by this historic building, due to which the property is under threat and requires maintenance or conservation strategies to safeguard it from further damage. To document the existing premises of OICCI building, the Heritage Cell – Department of Architecture and Planning, NED University (HC-DAPNED) has been appointed as conservation consultant; and is assigned with the a scope of works as follows: Step I: Documentation (Mid February - March 2013) The first phase involved detailed documentation of the property using on-site measured survey and photographic records. Under this first stage of the project a set of complete drawings is produced following the principles of architectural conservation. The set of drawings include: 1. Site Plan 2. Plans ( different levels of the property) 3. Elevations 4. Sections (covering all details of the interiors and exterior) 5. Details of the important Architectural features Prior to documentation a set of drawings including Ground Floor, First Floor and Roof Plans were provided to the HC team but the authenticity of the documents was not proclaimed thus work had to be initiated from scratch; commencing from February 14, 2013, by a two member team of HC-DAPNED. Through an extensive twenty days field work undertaken by the team, data was collected on basis of which the first draft of measured drawings was produced. Stage II: State of Conservation Report – Proposals and Recommendations (April – May 2013) The second phase of the project comprises of preparation of a ‘state of conservation’ report which includes a detailed description of the identified issues and problems related to the maintenance and structural stability of the property. The report first identifies the values and characteristics of this listed property, which are required to be appreciated and retained in the proposed scheme; and further lists the alterations/ existing problems in the original building materials, along with remedies and/ or repairs recommendations. The report also incorporates a review on the previous interventions that had been carried out on the historic structure over the years. In the light of identified causes of decay and damage to the site, this report presents certain guidelines to be followed by all other consultants engaged in the project to prepare their proposals keeping in view the heritage conservation principles. The final proposals will have to be submitted to the Department of Culture Government of Sindh by the in-charge officer himself with a request for issuing an NOC to carry out the conservation works on said property.


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DOCUMENTATION AND DATA COLLECTION (Methodology and Constraints) Prior to formulating conservation policy for any monument, a detailed survey and documentation of the existing status of the building has to be undertaken. The data collected in form of photographs, site observations, notes and sketches, are then sorted, evaluated/ analyzed and finally used for developing recommendations. The various stages included in a conservation project are; Documentation (measured survey and photographic) Identification of Problems Analysis of Problems Suggestions for Remedies On the basis of all required information as gathered, a comprehensive conservation plan can be formulated. Documentation and data collection is the first and most important stage for initiating any conservation project. The purpose of documentation is to know the existing status and conditions of the monument, and be able to understand its problems in terms of materials, structural deformations and instabilities, deterioration and its causes, alterations, etc. The documentation surveys are carried out to know the monument and experience it in its exiting state. Information at this stage needs to be gathered with precision and should be very authentic. Carrying out a measured survey of the building/s at hand is the major component of the documentation stage. A Measured Survey includes precise documentation of building plans, elevations and sections. In the case of OICCI, there existed only the floor plans of the building. But they were much undeveloped and their authenticity was questioned too thus work on building plans and layouts were commenced afresh. It took 3 months rigorous efforts of field survey and preparation of measured drawings of the buildings. Besides preparation of measured drawings, a photographic documentation of the building was also carried out. The conclusions are drawn on the basis of visual observations undertaken during the site survey. All the practices, procedures and the techniques to be adopted in the conservation of this building are included in the proposed remedial measures. Quantification of remedial work does not come under the scope of this report.


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DESCRIPTION OF THE BUILDING Overseas Investors Chamber of Commerce & Industry (OICCI) established in 1860 as a forum of investors of Karachi. This forum served and still is promoting the foreign investments thus performing a notable part in the economic growth of the country. The existing building of the OICCI was opened in 1927 as the inscription on a stone plaque at the building reveals. Prior to this the forum was housed at a different location (un-identified). The ground plus one structure is constructed over a corner plot no. SR-2/8. Along with the main building block, there are two small structures added on both sides of the structure to incorporate the growing needs of the users and/or to incorporate various additional services. Main building with these two building blocks is oriented towards Talpur Road (Woods Street). This road allows traffic one way coming from I.I. Chundrigar Road (Mc-Loed Road) and going towards Shahrah-e-Liaqat (Frere Street). At the time of its construction under British rule, the boundary was low in height (Picture-1) as compare to what it appears today.

The overall construction of the building is carried out in pink Jodhpur dressed stone masonry, which was considered as the best quality building stone in the region. The internal walls are plastered with CC plaster and painted with several layers of enamel paints. The façade treatment is done very simply yet in a bold manner. All around the building runs multiple bends of cornice/ moldings at parapet level. At certain locations window openings are covered with net (jallies) but most of the windows still maintain their original design. The ‘U’ shaped building plan offers linear arrangement of various rooms with minimum architectural embellishments around a central hall which is currently bifurcated to serve two different organizations housed in same premises, i.e., one portion is occupied by OICCI activities and the rest is rented out to Burj Bank. The first floor of the building is lying vacant at present. Along South East and North West sides two blocks are added to the main building. These blocks are called as Annexes 1 & 2 respectively. The Annexes located along South East side is currently

Picture-1: At the time of Inauguration of the OICCI © http://oicci.org/index.php/about-the-oicci/


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vacant. Whereas the first floor of other annex is vacant. These later added structures on two ends of the plot reflect the development phase of the original historic content of the site, thus should be considered worthy of preservation and incorporated in the restoration/ renovation scheme. Façades of the Building The most significant feature of the building is its entrance portal on South West façade along Talpur Road (Woods Street). The architectural style of this portal is a typical representation of British Raj period architecture in the region. Simple in architectural vocabulary; the only dominating feature adorning this faced is the 25’ high Doric orders columns. It is a G+1 storey structure with a partial construction on second floor, having a total height of approximately 38 ft (from ground line till parapet wall). All around the 4 façades multiple bends of cornices run at a height of 27’-6” (approx). South East and North West façades are quite simpler with large window openings of approximately 7’ to 8’ high. These windows are intact in their original shape and size except three windows which were altered to incorporate the changes in internal layout of the building. North East façade is relatively simple with less windows and it is the most affected façade with time to time alterations. The ground floor is approached through a 65 ft (approx) wide front portal stepping up 8 steps. The first floor is accessed through a well maintained 6’ wide ‘U’ shaped RCC staircase located in the portion currently occupied by Burj Bank. There is a secondary staircase to reach to first floor. It is a 4 ft wide (approx.) timber staircase located in a corridor towards the left side of main hall in the area as currently occupied by OICCI. The timber staircase is not in use at present as it is messed up with extra storage stuff. The flooring of the entire building is done in pigmented black and white CC tiles. The CC tiles on both floors are in a good state of conservation; except for small patches where repair work is needed.

Area Occupied by Square Feet Square

Yards Square Meters

Area % w.r.t to Plot Area

Entrance Portal 689.13 76.57 64.02 2.08%

Main Building Block on Ground Floor excluding Toilet Block and the Service Area at back

10,486.76

1,165.20 974.25 31.69%

Main Building Block on First Floor including Toilet Block

10,895.71

1210.63 1012.245 32.929%

Annex 1 (located along right side of the Main Building Block)

1,509.77 167.75 140.26 4.56%

Annex 2 (located along left side of the Main Building Block)

1,519.16 168.80 141.13 4.59%

Toilet Block and the Service Area at back 528.00 58.67 49.05 1.60%

Total Covered Area 14,732.82 1,636.98 1,368.72 44.53%

Open Spaces 18,355.46 2,039.50 1,705.28 55.47%

Total Plot Area 33,088.28 3,676.48 3,074.00

Area Occupied by Square Feet Square

Yards Square Meters

Area % w.r.t to Plot Area

OICCI Building on Ground Floor 5260.77 584.53 488.74 15.89%

Burj Bank on Ground Floor 5,225.99 580.67 585.51 15.79%

Annex 2 on First Floor 1221.07 135.67 113.44 3.69%

Main Building Block on Second Floor 1332.708 148.08 123.81 4.02%


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PRESENT STATE OF CONSERVATION/ MAINTENANCE

The Overseas Investors Chamber of Commerce & Industry (OICCI) building has been fairly lucky in this regard as it has been in constant use since the time of its construction. Regular day to day upkeep rituals as well as occasional repair and maintenance procedures have made it possible for this historic premise to survive till the present day in a relatively better condition. But still the building has undergone various modifications over the period of time.

The building has been in use since its inauguration in 1927. During the eighty-six years span of its existence the building has undergone various changes and alterations, to accommodate the growing needs and activity developments. In order to keep the building in efficient use its continuous maintenance and regular upkeep processes were also undertaken by the successive managements of the building. Since the regular maintenance and upkeep processes for historic buildings are not considered as areas of specialization in our country, several interventions undertaken in good faith turned into a hazard for the historic structure. Some of them do not support the aesthetic value of the structure and mark a negative impression on overall ambiance. This study has been undertaken to understand and identify the problems and shortcomings of the conservation process for the OICCI building, with the objective to suggest possible guidelines for the betterment of the historic property as the historic building materials and construction techniques are unique to their time and no longer commonly practiced. Due to this fact, generally labor as well as common professionals are not aware of the qualities and behavior of old days’ materials, thus tend to suggest interventions which in the long run prove to be harmful for the historic materials. The exterior of the building is better preserved showing some forms of deterioration of lesser intensity that are the result of natural decay and climatic factors. However, the back-side of the building has severe deterioration at several locations. Ground floor of the building is fully occupied and thus in better state. The most affected part of the property is first floor which is abandoned since few years (exact time period is unknown). However the first floor slab is completely intact at present but it is feared that due to an abandoned space it may fall apart with the passage of time. At present, the wooden doors and partitions are in good condition. False ceiling at certain areas is damaged and covered with spider webs. The overall condition of the floor is good, it only needs thorough cleaning and slight repair works. Structurally the building is sound and no major deformations are identified. However, minor forms of material deterioration and decay related to both weather and water penetration include issues like disintegrated mortar joints, cracks, soiling and weathering of external stone surfaces, macro and micro biological growth etc. The mapping of all forms of damages and deteriorations helps us understand and identify the causes of damage and deterioration. The suggested remedies take this understanding into account, thus attempting to first rectify or eliminate the source of problem and then approach the repair and maintenance measures.


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ARCHITECTURAL FEATURES OF SIGNIFICANCE:

1. Independent Compound The ground plus one storey structure is built within an independent compounded plot with surrounding open spaces, not visible from the road due to a 11’-10” high boundary wall. The main building covers an area of 10,486.7609 sq.ft on a plot of 33,088.28 sq.ft. This type of compound structures represents a unique plan typology of colonial period which is dying and threatened as time is consuming. This type of construction is now rapidly becoming rare because of growing commercialization and demolitions for new developments and high rise constructions; resulting in the loss of this historic environment. 2. Entrance Portal This Architectural module is seldom found in the historic buildings of Karachi. It is the sign of a magnificent edifice, usually representation of some public amenity. The OICCI building has a very huge and a welcoming entrance portal. It is designed in such a way that it seems to be so elegant and classy yet less ornamented. It is a raised podium of 3’-6” high from ground line, holding four identical sophisticated Doric order columns topped by a rectangular crown, which inscribes the name of the building. The design of the entrance portal is 10’-8” (approx.) projected out from the building. This solid ingress creates an enchanting impression over visitors while getting into the main building block. (Picture-2)

Picture-2: Magnificent Entrance portal


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3. Doric Orders Huge Doric Greek orders are the symbols of the glorious past of the Raj Architecture in Karachi. In OICCI the vertical shafts of the orders (column) stand 25’ vertically high resting directly on a simple circular base of 4’-2” dia. The circumference of the column reduces gradually and forms a conical shape. The shaft consists of 20 concave grooves and they are topped by a smooth capital (Picture-3). Usually the height of the Doric order is six or seven times the diameter of its base (Great Architect Vitruvius’s concept).

Picture 3 (a, b & c): Doric - Greek orders in OICCI at the entrance of the building

a

b

a c

http://en.wikipedia.org/wiki/Fluting_%28architecture%29


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Picture-4: Balcony & the decorative Iron Grill

4. Balconies

Balcony is a platform that projects from the wall of a building and is surrounded by a railing, balustrade, or parapet. There are three European iron-grille balconies in main building of OICCI created by 1’-1” projected slab guarded with 3’ high iron grille and metal doors opening inside the room, to view the courtyard. The balcony slab rests on stone console (a structural piece of stone applied to the wall) from a wall to carry a superincumbent weight. The overhang entrance portal provides a shelter to the balconies (Picture-4).

5. Decorative Cornices

A cornice is generally any horizontal decorative molding that crowns all around the building. The function of the projecting cornice of a building is to throw rainwater away from the building’s walls. Or it is also used as a decorative element of the building. In OICCI building, the cornices have very less decorative aspect and their function is to crown the building and the window openings on top of the building (Picture-5).

Picture-5: Decorative Cornice moldings at various

locations


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6. Magnificent Entrance Doors The arched door at the main entrance is the most interesting feature of the OICCI building. Most of the other entrance doors to various spaces in this building are also designed with elaborate detailing of the wooden frames with panel shutters in teak wood/ glass and brass hardware. Mostly, the doors have double shutters with ventilators above and finished with polish. There is a large variety of doors design found in the building in varying sizes (Picture-6).

Picture-6: Entrance doors at various locations


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7. Windows In OICCI building, the windows are recessed in the wall and thus no window projections are found. Most of the windows made of teak wood with glass panels are guarded with iron bars for security reason. Window design and sizes vary in the building on various facades of OICCI building (Picture-7).

8. Roundels A roundel is referred to a type of an Architectural element, generally circular in shape and comprising concentric rings. In case of OICCI building roundel is used in three different manners. The one located at the crown of the main building block is the simplest one where the façade is decorated with a high relief by a roundel with a raised piece of circular stone. Other type of roundel is found above windows where windows are topped by two concentric raised rims of stone. The third type of roundel is observed at the lower part of the boundary wall having a circular recess in the wall encircled by a raised rim having another relatively very small raised circle in the center (Picture-8).

Picture-7: Recessed windows at various locations

Picture-8: Roundels at various locations


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ALTERATIONS/ INTERVENTIONS/ ADDITIONS Alterations and modifications are often observed in monuments and/or historic buildings that have survived to present day. Under certain contexts, such interventions are considered as part of the historic development of the building and shall not be disregarded under any conservation policy. The OICCI building is also an example where a lot of changes in the original layout were done over the years, basically to accommodate the growing needs and changing technologies. Since all these changes were undertaken to make the functioning of the premises of the building more efficient and have now become a part of the building since long, there is no reason to propose any kind of reversal to the original state as it may damage the building further. All these alterations and changes should be given importance, but on the other hand they need to be examined for any diverse effects to the building fabric. If such cases are identified their possible rectification should be proposed under a well formulated program. Since the building is in constant possession of corporate sector, it has also endured several rounds of repairs in past years. In those repairs several changes and alterations have occurred but somehow the building has tried to retain its original character and proportion of built and open spaces. From an in-depth observation of materials a list of alterations is prepared as not being part of the original. These alterations must be addressed timely to prevent the further decay to the property. It is also recommended that all such later alterations must be reviewed in terms of their present compatibility with the building and decision for retaining or removing them in the restoration process should be taken up categorically. These later additions or the alterations observed are discussed as under.


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1. Main Building Block a. Partition walls – Space subdivision

The OICCI building was initially designed to serve as the Chamber of Commerce and at present, it is shared by two different organizations. For this reason several rooms and spaces are sub divided through partition walls on both the ground and first floors. While entering into the building, the huge entrence lobby of the building is observed as a divided space. The central hall along the same axis is also divided into two. The hall’s floor finished with pigmented cement tiles with boarders running all round, is now disrupted by partition walls erected to bifurcate the space. Each half has its own false ceiling. Separately both the portions are further divided into small chambers or the offices to accommodate the staff. Various partition walls are erected with the use of glass, wood and cc blocks (Picture-9). These walls can be removed carefully to restore the central hall in its original shape.

Picture-9: Partition Wall


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b. Altered doors and windows

Few doors and windows are altered to adjust the growing needs of the organization. A window on South east (right) façade of the building is altered and is transformed into a door to provide a direct access to the annex located next to it. This door is provided with mild steel staircases to step down from plinth level to the ground. The last window in the row is also vandalized by taking out the window panes and blocking them with cc blocks and creating two small ventilators. This is done due to the placement of a rest room in that corner. Similarly two windows on North East (back) façade are completely blocked using cc blocks. All these closed and altered openings affect the aesthetic of the façade and are recommended to restore into original shapes and design (Picture-10).

Picture-10: Altered Windows at Various locations


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c. Defacing of Building Façade

The three façades of the building except the South West (front) façade are defaced by several amendments and additions of extra elements. These mainly include exposed electrical wiring and plumbing lines running along the entire lengths of the façade. Unsightly and unplanned ACs out door units have also been installed at various locations, and are attached very close to the building façades.

A revised plan for all services infrastructure is recommended to clean the façade. The outdoor Ac units can easily be accommodated on the roof top instead of mounting them on facades (Picture-11).

Picture-11: Defacing elements attached to the façade at various locations


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d. Misuse of the Space round Toilet Block

Layout of main building is in “U” shape. The open space as created due to “U” shape accommodates a detached toilet block along North East (back) façade. At present, the rest of open spaces within “U” shape are used to place AC plant and the generator along with the storage of broken furniture etc. As the space is currently too dark with the bad order of water seepage it has become a breeding place for mosquitoes and other harmful germs. The overall condition of that particular area is very unhygienic and untidy (Picture-12).

Picture-12: Misuse of the space of AC Plant Area


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e. False Ceiling

Various rooms on ground and first floors are decorated with false ceiling; not only to reduce the height of the room which is approximately 15’high (exact height could not be measured at certain locations due to false ceiling) but also to provide room for air conditioning ducts. The entire interior of the building is ventilated mechanically through air conditioners and the windows are rarely opened. There is a variety of false ceiling designs and materials used on both floors. Though there is no consistency found in false ceiling profiles, however, the condition of false ceiling is very good except at very few places, it requires little maintenance and repair (Picture-13).

f. Addition of toilet blocks

On first floor a toilet block is added above the original detached bathrooms structure standing on North East (back) side of the building. This unit was probably added to cater the growing needs of increasing number of personnel serving there but currently the first floor is lying vacant so as this toilet block. The floor is covered with dust and the walls with spider webs.

Picture-14: Back elevation of the toilet block

on North East (back) side of the building

Picture-13: False ceiling at various locations on both Ground & First Floor


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2. Annex - I On South East (right) side of the main building block an annex is constructed with RCC frame and block masonry walls finished in color-crete (pigmented plaster). It is comprised of a big hall accompanied by a small room, a small kitchenette and a rest room. This whole unit is left abundant since several years (exact date unknown). This act has gathered layers of dust on floors and webs on vertical surfaces. On back side of the annex is the facility of lavatory for the lower staff of the OICCI. The condition of this lavatory is very unhealthy with no provision of electricity. The white floor tiles are entirely covered with filth and are in intense need of deep cleaning (Picture-15 & 16).

Picture-16: Toilet block at back side of the Annex-I

Picture-15: Images of Annex-I along South East (right) side of the main building block


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3. Annex- II Another annex is located on North West (Left) side of the building. Constructed in RCC frame with block masonry walls finished in color-crete (pigmented plaster), this part is currently in use as an office and is well maintained. Its first floor is abundant like the rest of the first floor of the main building block (Picture-17). Various alterations are mapped below to understand and identify the causes of damage and deterioration. The suggested remedies take this understanding into account, to first rectify or eliminate the source of problem and then approach the repair and maintenance measures.

Picture-17: Images of Annex-II along North West East (left) side of the main building block


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IDENTIFIED PROBLEMS IN BUILDING MATERIALS & THEIR CAUSES OF DECAY AND DAMAGES

1. Lack of regular maintenance Over all the building is well maintained but deficiency of regular upkeep is also observed. Maintenance of historic buildings requires continuous conservation measures; decision making for which requires an appropriate understanding of the historic materials and their construction techniques, structural systems and their behavior, their defects and causes of decay, etc. In case of OICCI Building, a few conservation measures taken in past are evident from the present state of the building, which probably were carried out as the remedial measure perhaps some decades ago. Some alteration without any regard to the aesthetics of the building and sensitivity of the old-days materials were carried out. Conservation of historic buildings is an on-going task, where the objective is to keep the premises intact and surviving for the future generations to witness, in its true spirit and essence. Only on basis of appropriate knowledge one can take proper conservation decisions that would prove to be beneficial for the building, and ensure a longer life to the historic structure in question. The decision for conservation of Overseas Investors Chamber of Commerce & Industries (OICCI) is a positive step in this direction. By adopting an appropriate conservation strategy the stakeholders of this important historic property will be doing a positive contribution towards preservation of Karachi’s declining heritage.

2. Site Level/ non availability of natural gradient The site of the OICCI is spread over 33,088.28 sq. ft of area of land, out of which 44.53% area is occupied by main building and various other ancillary structures. Remaining 55.47% area is used for various activities including car parking. The overall external pavement (CC pavers) of the building is uneven and is not leveled. The faulty slopes at the site cause water trapping in rainy seasons and during washing of the premises. With the passage of time, the road level has gone up and thus a reverse flow of water is observed at the premises during heavy rains.

It is important to rectify the floor gradient properly by removing and relaying of cc pavers and introduce threshold at the entrance to stop water penetration from road to the premises in rainy days.

3. Deteriorating Stone

Stone decays with the passage of time but with precise care and regular upkeep, the life of same stone can be strengthened for beyond decades. The construction of OICCI Building is carried out in pink Jodhpur dressed stone masonry. At present, the conservation state of the stone is dissimilar on each of the façades. South West (Front), South East (Right) and North East (Back) façades are exposed to sun directly and are moderately in good condition. Where they are exposed to wind erosion, the sun rays help in drying out the rain and any moisture manifestation. On contrary, the North West (Left) façade is facing stone decay. This façade is actually covered with a temporary shed and along that façade; the ACs outdoor units are mounted to approximately each window. Constant water dripping from Ac units under shade is causing decay in stone surface. At certain points the stone wall is deteriorating due to rising dampness up to the height of 3ft maximum, which is assumed due to watering the plants placed adjacent to it (the wall). The


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moisture trapped in mortar joints or cavities in rubble stone masonry results in degradation of stone. Measures should be taken to stop the water penetration into masonry, or else this problem will become more crucial. It is highly recommended to place vegetation at a certain distance from the stone walls or some sort of clay pots underneath the plants be introduced, so that the extra spilled water do not affect the stone walls (Picture-17).

Picture-17: Deteriorating façade stone at various locations


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4. Soiled Flooring Surfaces

The flooring on ground floor is done in pigmented black and white cc tiles with black boarders all around it. This flooring is in fairly preserved condition except for a few locations where minor damage is observed in form of cracks and broken tiles. These damaged areas can be dealt with spot repairs/ replacements. Other than these few locations the rest of flooring tiles are intact and firmly in place. Flooring on first floor is completely dirt/ dust accumulated, to an extent that a common person would be unable to distinguish between the current and the original condition of the floor. Due to prolonged disuse and lack of regular cleaning/ maintenance this flooring presently appears in a bad state. The accumulated dust layer and soiling requires proper cleaning. Measures need to be taken to prevent any damage to this original flooring during the repairs of structural members. The floor has 100% potential of being restored entirely only if the proper cleaning and proper polishing is carried out. The tiled flooring of exterior surfaces has an accumulated layer of soiling, which is more intense in areas where faulty slopes do not allow rain water to flow till it evaporates through natural process. The entire floor requires proper cleaning and repair for broken tile pieces (Picture-18).

Picture-18: Soiled floors at various levels in the building of OICCI


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5. Dirt Accumulation and Soiling on Horizontal Surfaces The OICCI Building is located along the main road i.e. Talpur Road (Woods Street) and thus accumulates dirt due to heavy traffic and less vegetation and foliage between the building and road. So the environmental pollution has great impact on the building especially it’s South West (front) and the South East (right) facade whereas the rest of two façades are not affected much due to polluted air. The façades of this building show some signs of soiling, apparent by a change in coloring of stone, due to dirt accumulation, growth of mirco-biological film and bird droppings, especially on horizontal surfaces such as cornices and the windowsills etc. These would require proper cleaning using mild chemical treatments and scrubbing. More stubborn stains would require intense cleaning with stronger chemicals (Picture-19). See Appendix I.

Picture-19: Dirt Accumulation and Soiling on Horizontal Surfaces


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6. Black Crust Formation Besides general soiling due to consolidation of atmospheric dust, various locations of the property also show another form of stone deterioration i.e. the black crust formation. Presence of hazardous particles in air (air pollution) and constant presence of moisture results in formation of such type of black crust. The back crust forms on unexposed or shaded areas where sun exposure is very negligible, i.e. is usually the crevices of carvings or gaps of minor details or on vertical surfaces where rainfall striking on damaged horizontal ledges, produces a run off film down the wall. Black crust is a combination of runoff bio-film, dried pigeon droppings and dust accumulation when dry; this film turns into black crust adhering to the stone. The black crust is most likely to cause excessive weathering of the stone during humid climatic conditions, when water content in air is very high. Black crust is on OICCI Building is seen on vertical surface on North West (left) façade which is opposite to the sun direction, under cornices, in shaded areas under projections and in the carved areas of Ionic capitals (Picture-20).

Picture-20: Black Crust formation at various locations on the building


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7. Seepage

A brief examination of the ceiling on the ground floor indicated water seepage stains at a particular location in conference room no.1. Since no other source of water (supply / drainage lines) is observed at the particular point (above or below), it is assumed that this could be a result of any water leakage through ducts installed behind the false ceiling. Removal of a certain portion of false ceiling is recommended for further investigation of water seepage (Picture-21).

8. Macro and Micro Biological Growth

The biological growth is observed at OICCI Building due to localized issues of water penetration. Small patches of stone masonry are affected by this phenomenon. The problem of rising dampness is not found all over the site but the exterior floor is not leveled and cause the water (used for washing) and rain trap in these unleveled pockets and act as rising damp, particularly those sites which are not exposed to direct sun light. The moisture trapped in mortar joints or cavities in stone masonry results in promulgation of biological growth. As the plants are growing bigger they are dislodging the masonry and damaging the flooring. Measures should be taken to stop water penetration into masonry, or else this problem become more severe. The removal of such biological growth and prevention measures must be taken immediately (Picture-22).

Picture-22: Macro Biological growth at roof of OICCI Building

Picture-21: Water Seepage in the ceiling of Conference Room no. 1


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9. Staining due to Bird Droppings

The design of OICCI Building carries cornices of diverse sizes at different levels that inhabit birds in them. The problem of birds dropping is quite severe at the entrance portal right between the columns. It appears to be an ugly appearance to the building; and may also cause some damages to the stone because of their acidic content. Furthermore, the bird’s droppings play a vital role in the development of biological growth. Once the acidic content of these droppings came in contact to moisture there propagates a biological growth. Furthermore the placement of building in such a way that it faces the only landscaping of the site. The trees inhabit birds that eventually rest at the cornices, parapet walls and roof projections and leave their droppings. A constant cleaning of such bird droppings shall be exercised (Picture-23).

Picture-23: Bird’s dropping at the Entrance Foyer


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10. Water proofing of roof

An exercise of water proofing at the top roof slab was carried out some years ago using conventional method of applying bitumen followed by a layer of fabric sprayed with acrylic paint as a protective layer. There is a complaint of water seepage during rains as the water proofing layer is deteriorating and overlapping joints are opened at few places (Picture-24).

Picture-24: Top roof slab with water proofing layer


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PROPOSED REMEDIAL MEASURES AND CONSERVATION INTERVENTIONS

In view of the material problems identified in OICCI Building project, following list of remedial interventions is proposed. These include repairs, cleaning and consolidation where required; and maintenance measures. The general approach is to retain the original materials and design proposal with minimal additions or change. Each of the proposed intervention is described briefly as follows:

Sealing of cracks on walls The vertical surfaces of the entire building need close examination for any cracks or open mortar joints, before any cleaning of surfaces is attempted. In case of OICCI building no major cracks are observed. Cracks of a minor degree are visible in the mortar joints and other non-structural elements. These will be treated with lime based fillers. Any loose mortar should be brushed off, and the gaps or cracks will be repaired with fine lime mortar of approved finish color & quality. The damaged repair mortar of previous maintenance jobs must also be checked closely and if loose or disintegrating it should be carefully taken out and the gaps/ open joints repaired with proper grouting and filling material. For larger cracks or open mortar joints lime based repair materials are to be used. See Appendix - II for preparation of lime mortar.

Cleaning of stone walls (Exterior) The stone surfaces need to be cleaned as they show soiling due to dirt accumulation and soiling. In the first stage of cleaning all dry and loose dirt particles will have to be brushed off with hard brush, carefully ensuring that no loose particles of the stone itself are lost in the procedure. Such loose or detached pieces of stone should first be consolidated and repaired only then the general cleaning and washing should proceed. General washing of the entire stone surfaces will have to be done with mild soap and distilled water. Only after this initial cleaning, the more stubbornly adhering dirt patches, such as black crust formations, etc. will be treated. For a detailed, recommended process of stone cleaning refer to Appendix - I of this report.

Cleaning and repair of interior floor The internal floors must be cleaned and spot repaired for the identified damaged areas. The entire flooring needs proper cleaning to remove soiling and other stains, and polished after the repair and cleaning measures are satisfactorily undertaken. For a detailed, recommended process of cleaning of marble flooring refer to Aappendix - III of this report.

Re-painting of interior and exterior spaces In interior spaces the peeling paint layers indicate that all of these surfaces have been repainted several times. The walls and ceiling also have several accumulated layers of paint, which partly contributes to the peeling and chipping. All painted surfaces will first be cleaned and properly scraped to the extent that all previous layers of paint are removed and the plaster surface is clearly visible. The surfaces will then be sanded with a coarse grade emery paper. The surface will then be prepared for application of a fresh coat of paint (any water based); prior to which it should be ensured that no chemical treatments were previous applied on these surfaces which are causing the peeling of paint. If they were, then clean it for chemicals then apply paint layers. Water based paints are emphasized due to lime plaster applied on stone walls as old-day materials properties.


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Repair of damaged false ceiling (first floor) Small parts of the false ceiling are damaged and soiled with spider webs on first floor of the building (probably due to lying vacant over times). This will have to be repaired with caring repair technique; carefully cutting out the damaged area and patch-working with reproduced replacement of damaged portion.

Water Proofing of roof top In order to eliminate the water leakages through roof, proper water proofing of the roofs needs to be re-done. For this purpose the entire roof should first be properly cleaned and checked for the proper slopes, ridges and valleys. Apply bituminous waterproofing membrane in consultation with the manufacturer (Hy-Grip or equivalent) with appropriate detailing at the joints, corners, with precise care for overlapping between sheets and at the joint of parapet wall with the roof surface.

Under-utilization of Space The survey of the OICCI building shows that first floor is not in use and is left to decay. The abandonment is causing serious damages to the entire floor. The floors are subjected to dust/ dirt accumulation and the false ceilings are crumbling with the passage of time. The entire space can be revived very easily with emphasis on efficient space utilization, through which occupancy of the building can be increased to a great extent. The unused spaces of first floor should also be utilized with appropriate functions.

Prevention and removal of biological growth Presence of moisture is the prime cause for biological growth. The main sources of water in case of OICCI are identified and discussed above. The building is suffering with the problem of micro biological growths very minutely, so some appropriate measures for cleaning of surfaces soiled by organic growth can be carried out if the presence of such biological growth is observed. Macro plant growth can be killed by spraying with an appropriate weed killer. It is important to kill the roots and remove any humus which may encourage future growths. Acid can be injected by digging minor holes near the affected areas as well. Any gaps or cavities created due to the removal of plant growth should be repaired/ filled with lime mortar.

Long term maintenance program As the absence of any foliage attract dust, smoke and pollution of constantly moving vehicles, and leave a negative impact on the building façade directly, a long term maintenance program must be initiated.

Periodic Checking of Sealant Treatment on all External Surfaces The chemical sealants and repair mortars used on all external surfaces should be checked after every six to twelve months for any signs of damage of decay. Their performance against water penetration should also be checked on site after every rain. Any small indications of decay, damage or disintegration should be immediately attended and immediate measures should be taken to repair these damages before they get magnified. For a detailed, recommended process of sealant and lime mortar treatment refer to appendix -II of this report.


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Immediate Wiping of Floor Surfaces after Rains and Wet Cleaning As stated above the levels of the exterior floor is not leveled so after every rainfall all surfaces should immediately be wiped clean of any standing water pools. Any wet cleaning undertaken for the building must be properly monitored ensuring that water is not splashed or jetted with high pressure towards the façades. Each wet cleaning should terminate at proper drying up of all surfaces. Use of saline/ brackish water should be avoided at any cost.

Discouraging/ Controlling Birds to Perch In order to reduce the menace created by the presence of birds on the site, some measures can be taken to control bird population; and also discourage them from settling on to the ledges and horizontal surfaces of the building. A few techniques commonly used internationally include; Stretching a synthetic mesh of unobtrusive color across potential roosting sites such as deep ledges, window openings, roof ridges, etc. But these can have an unaesthetic appearance on the building Strips of gel applied on ledges where birds may roost. This provides an insecure footing, discouraging the birds from settling down. But once the gel dries off it can become a nuisance in itself, because it adheres to the surfaces rigidly and could not be easily taken off. Low voltage wires, with small electric charge, can be stretches between insulators along the ledges. Other known methods are trapping birds and removing them from site, shooting or scaring them away by producing noise. But these methods seem cruel and would be criticize by the bird lovers. Provide an alternate birdhouse in the premise. As a long term preventive measure regular cleaning of the areas which are soiled by bird droppings should be made as part of the continuous upkeep routine. This will ensure that the build-up does not happen and surfaces are washed off before the soiling becomes so severe that it would require professional cleaning measures.

The above mentioned remedial measures should follow a logical sequence to ensure optimum results.


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CONCLUSION: The conservation report is concluded by summing up the following remarks: Conservation of historic buildings is an on-going process, where the objective is to keep the premises intact and surviving for the future generations to witness, in its true spirit and essence. Only on basis of appropriate knowledge one can take proper conservation decisions that would prove to be beneficial for the building, and ensure a longer life to the historic structure in question. The decision for conservation of Overseas Investors Chamber of Commerce & Industries (OICCI) is a positive step in this direction. By adopting an appropriate conservation strategy the stakeholders of this important historic property will be doing a positive contribution towards preservation of Karachi’s declining heritage. Maintenance of historic buildings requires continuous conservation measures, decision making for which requires an appropriate understanding of the historic materials and their construction techniques, structural systems and their behavior, their defects and causes of problems, etc. Without gaining this understanding remedies should not be suggested, as they could result in damaging the original materials. Only on basis of appropriate knowledge one can take proper conservation decisions that would prove to be beneficial for the building, and ensure a longer life to the historic structure in question. Some guidelines are attached herewith as annexure.


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APPENDIX - I Cleaning of Stone Surfaces The stone surfaces of the monument show dirt accumulation as well as black crust formations at various locations. To clean the entire façades, chemical cleaning by the following process is recommended. Proposed method for cleaning of stone: Step 1:

Gently brushing off all loose particles; sand, dust, etc. Mapping of any loose fragments as well as dislodged pieces of stone should also be done at this stage. The particles or pieces of detached stone that are of substantial size should be examined for strength and if found in good state are recommended to be fixed to their original location by grouting and joining techniques. Step 2:

Temporary filling or repairing of the open mortar joints and decayed pointing is to be done before starting wet cleaning. Step 3:

Gently spray distilled water on the stone surfaces to be cleaned (starting from upper parts). Scrub with sponge or nylon brushes and rinse off the surface with spray of distilled water. Let the masonry dry off. If black patches of dirt or black crust are still observed then clean only these parts with an Ammonium Bicarbonate poultice, in the following way. Step 4:

Cleaning of soiling and black crust with ammonium bicarbonate solution. Before deciding upon the concentration of the solution to be used, treatment test samples should be done. The selected sample treatment areas should be characteristic of the deterioration or soiling found on the building. Sample areas should ideally be as inconspicuous as possible. It is recommended to adopt a sequential approach, starting with the least aggressive methods first and gradually increasing the applications until an acceptable level of cleaning is achieved.

If the biofilm is wet, it should be allowed to dry first. Dried bio-film will be brushed and surface applied with the ammonium bicarbonate poultice. Preparation and Application of the Poultice:

Prepare 10% solution of Ammonium Bicarbonate in water.

Dissolve the particles thoroughly, and sieve the solution through very fine fabric (e.g nylon stockings).

Add paper pulp to the solution till it gives a thick paste.

Brush off and clean the trial surface area.

Take the pulp in hand and squeeze off extra solution, then throw on the surface and gently spread with fingers.

Leave the poultice on surface, for a while, checking at each 10 to 15 minutes interval.

Take off the poultice at a time when the desired level of cleaning is achieved.

Brush the surface and wash off with water.


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It is recommended that the sample cleaning should be started with the least concentration of solution i.e. only 10% with minimum time of application i.e. 15-30 minutes. If the crust does not remove then only the concentration and time is gradually increased. But the concentration of solution should never go beyond 30% as this is the level of saturated solution. In case the higher concentration solutions also do not work then a sample with very small percentage (only 5%) of EDTA (Ethylene-diamine-tetra-acetic acid) can be attempted. Poultices should be prepared; first those with a solution in water of 10% ammonium bicarbonate then gradually increasing in concentration if the 10% solution does not give effective results. 25% ammonium bicarbonate up to 30% saturated solution of Ammonium Bicarbonate. If the poultice is required to be left for a longer time span then it should be covered with a sheet of polythene and left for a few hours. It is then cleaned by a sponge, dipped in distilled water. If algae persist in certain spots, these can be treated with biocide treatment. This is done with a solution of 10% benzyl chloride or 2% zefiran in water. But this should be done after the necessary repair works. Step 5: Repair work, where deemed necessary should be undertaken after cleaning with poultice and before biocide treatment. The lime mortar used in all repair works must be prepared according to the specifications given in Appendix III.

Re-pointing and filling of gaps with permanent lime mortar. The mortar is to be applied with metal spatulas, firmly pushed into the gap and further compacted with a hard sponge. The extra mortar on surface should be cleaned with a wet sponge.

If there are any deeper cracks or fissures these should be filled with mortar using hydraulic lime.

All horizontal surfaces of windowsills and cornices to be sealed, by covering the whole surface with a layer of lime mortar. Once the surfaces are sealed the water will drip over the edges of these surfaces. These areas should be regularly monitored and repaired whenever required, Step 6: If salts have penetrated inside the building, they will start to appear on surface in the form of efflorescence once the masonry is dry. These can be cleaned by paper pulp technique. This should be done after the problem of dampness penetration has been dealt with. First the building will be aired and allowed to dry completely. Salt deposits/salt crusts or efflorescence that appear on surface after drying, can be simply brushed off. The remaining salts can be cleaned with paper pulp technique. In this method, blotting paper sheets or paper pulp wetted with distilled water, are applied on areas that have crystallized salts. The paper is left to absorb all soluble salts, and then taken off. Repeat the process as many times as required till salt efflorescence does not appear any more.


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APPENDIX - II: Lime Mortar Treatments Lime mortar treatments are to be done for damaged or decayed mortar joints, as well as for re-pointing and filling of gaps in masonry. It can also be applied as a protective layer on horizontal surfaces, for prevention against further deterioration. Lime mortar of specified composition should be used for this purpose. It is observed that previous treatments of lime mortar are done along the junction of vertical and horizontal surfaces. The application of this repair mortar seems somewhat clumsy. The strength and porosity of these repair mortars need to be checked before a decision for their removal could be taken. If too porous and damaged/ cracked in most areas then it would be recommended to remove it from all places with gentle chiseling, hammering or scrapping. After a thorough cleaning of the loose mortar, all open joints and gaps in joints should be re-pointed with lime mortar. Loose stone fragments can also be consolidated by grouting with lime mortar.

Preparation of lime mortar for repair: The lime mortar to be used for repair works should have higher porosity and water absorption, whereas less density and strength than that of stone. Their binder-aggregate ratio is different from the ones normally used. Generally, binder and aggregate ratio in mortar is 1:2 or 1:3. Whereas, laboratory tests of old plaster samples of British period repair lime mortar, show lime (binder): sand (aggregate) ratio of 3:1. This lime mortar has better cohesive properties, thus recommended for used in all repair works. The lime mortar prepared for repair of joints, filling of gaps, and protective coating of horizontal surfaces should either have a ratio of 3:1 (lime : sand) or it should be 1:3 (lime : aggregate) in which two parts of the aggregate should be of crushed limestone of the same type as used in the construction of the building. This mortar should have higher porosity and water absorption capacity, whereas less density and strength, than that of stone used in the building. In addition to this the mortar samples collected from the site should also be sent for an analysis of their composition and properties and the repair mortar prepared in accordance to the findings.


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APPENDIX - III Polishing of Marble Surfaces (Floors/ slabs)

File the surface with Silicon carbide paper – starting with rougher paper and then gradually with finer paper.

Finally the surface is polished with cloth and some metal oxide like tin-oxide (better for most stones) or lead oxide. (Jewelers use similar method for polishing stone).

For building stone mechanical disks are used for polishing stone slabs.

Starting first with 180 paper (wet with water); then 250, 320, 500, and end with 600

For very rough stone surface smooth it first with machine and then finish with finer grade paper.

OVERSEAS INVESTORS CHAMBER OF COMMERCE & INDUSTRIES … · The project of ‘Documentation and...

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