Insulation & Airtightness Continuity Report with Shadow Study
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Transcript of Insulation & Airtightness Continuity Report with Shadow Study
Insulation Continuity and Airtightness in Construction with Solar Study
Student Name: Jonathan Flanagan Student Number: G00262330 Date: 21/01/15 Revision: 01
Galway Mayo Institute of technology
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Table of Contents Cluain Mhuire Seminary Background ..................................................................................................... 3
Insulation Continuity ............................................................................................................................... 4
Airtightness ........................................................................................................................................... 19
Solar Analysis ........................................................................................................................................ 25
References ............................................................................................................................................ 28
Galway Mayo Institute of technology
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Cluain Mhuire Seminary Background
Fig. 1.1 Cluain Mhuire Seminary
Cluain Mhuire Campus was built in 1920 and is located in Wellpark, on the Monivea
Road approximately one mile from the city centre. Its original function was that of a
Redemptorist Monastery which opened its doors in c.1940 for students that were
undergoing training for the priesthood. The G.M.I.T. campus was later founded in
1998 is currently in operation as the Centre for Creative Arts and Media specialising
in courses in art & design, textiles and film & documentary. The Campus is listed on
the NIAH website as being listed as a protected structure
The chapel sits east of the main four storey monastery building, it features high
ceilings with trussed arches, stained glass windows (some damaged due to
vandalism) and hand cut limestone masonry and externals stone walls with a
thickness of 620mm. The altar is to the South of the building with a number of
confessional boxes featuring arched entrances along each side wall. There is a
narrow stairway to the rear of the building leading up to a gallery overhead. A small
sacristy is located to the South-West of the chapel just off the main alter with its own
entrance door. The site itself is not extremely historic as seen from the old the OSI
maps of Galway. The monastery was built on a blank site. In our Detail & Design
project we are required to provide a new modern extension on the existing site and
also carry out retrofitting and refurbishments on the existing protected structure, this
ties in with our Innovative Architecture module as we are to improve the buildings
energy standards. The fact that it is a protected structure may limit our design
interventions to the buildings envelope. Airtightness and insulation will be looked at
in depth in order for us to achieve the energy standards required for both the existing
buildings and its extension.
Galway Mayo Institute of technology
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Insulation Continuity
What are U-values?
Put simply, a U-value is a measure of the rate at which a material loses heat built up
inside it. A high U-value in a material demonstrates a poor thermal performance and
a low U-value indicates a good thermal performance. We want good thermal
performance of course.
U-values are one of the most important factors in predicting how a building will
perform in terms of energy efficiency and carbon emissions.
All new building projects and upgrades to existing structures must comply with the
building regulations set out in TGD Part L 2008 for buildings other than dwellings and
TGD Part L 2011 for dwellings. U values are first calculated at the early stages of a
project to meet these requirements.
Fig. 1.2 Table 2 Elemental Heat Loss Method TGD Part L (2008)
This table is extracted from TGD Part L and shows U-values required to meet the requirements set out in the document at or below these values at different parts of the buildings envelope. It is smart to follow these regulations especially if you want to future proof your design, in this case you will try to achieve the lowest U value possible for each element of the building which will have you crossing over into the realm of the passive house standard. The most important parts of this table that are relevant to my project have been highlighted in red.
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Variety of Insulation: There is an abundance of Insulations available from many different manufactures at home here in Ireland and Internationally with some manufacturers providing environmentally friendly options. Different thicknesses and material properties will have different U values associated with them. Natural low density Insulation’s like sheeps wool would require a larger dimensional thickness than a high denisty Insulation. This section of the report will highlight the most suitable options that can be used in the extension and existing structures build up.
Existing Wall
Fig. 1.3 West facade of existing chapel structure
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Below we can see the existing external masonry wall built up inside u-wert.net U-
value calculator, it is currently achieving a U-value of 2.07 W/m2K which is showing
us that the building is suffering in its thermal efficiency.
Fig. 1.4 U-wert.net U-value calculator
Fig. 1.5 U-wert.net Illustration of the different layers within the wall build up
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For the existing building and new extension I have decided on a choice of three
different Insulations to test and report upon:
Existing Proposal:
Aspen Aerogel Spaceloft
Fig. 1.6 Aspen Aergoel Spaceloft 10mm blanket
Aspen Aerogels' Spaceloft® is a flexible aerogel composite blanket designed for
insulating buildings. It can be used both externally and internally on existing or new
walls and is screw fixed to surfaces using thermally broken mushroom head fixings
that ensures no cold bridging.
The following is a list of Aerogel spacelofts’s physical characteristics:
Lambda 14mW/mK to 18mW/mK
5mm & 10mm blanket thicknesses
Excellent Vapour permeability (μ = 5), Extremely Hydrophobic – withstand hydrostatic Head test to 80cm
Euro Fire class C or A2
Will not promote mould growth, first class indoor air quality test result
Good impact sound absorption, up to 20% light transmission
This product is considered to have a clean environmental profile.
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Proposed Wall Build up with Aerogel Space loft inside U-wert.net calculator:
Fig. 1.7 U-wert.net U-value calculator
As we can see if we use 20mm of Aerogel Space loft within the above wall build up
we shall achieve a U-Value of 0.54 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.60 W/m2K for
alterations to existing buildings.
Fig. 1.8 U-wert.net Illustration of the different layers within the wall build up
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Gutex Multitherm
Fig. 1.9 Gutex Multitherm
Gutex Multitherm is a moisture resistant insulation wood fibreboard with single-ply
construction and homogeneous cross section, it is an ideal sarking board for exterior
walls under facade facing.
The following is a list of Gutex Multitherm’s physical characteristics:
Uniform board dimensions make installation quicker and easier
Homogeneous, single-ply construction
Makes structures wind-tight
Superior moisture resistance due to hydrophobic treatment
Ideal for upgrading the thermal insulation of existing structures
Reduces thermal bridging
Maximum protection against the heat in summer
Significantly improves soundproofing
Regulates humidity
Allows vapour diffusion
Wood is a sustainable, recyclable natural resource (natureplus® certified)
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Proposed Wall Build up with Gutex Multitherm inside U-wert.net calculator:
Fig. 1.10 U-wert.net U-value calculator
As we can see if we use 40mm of Gutex Multitherm within the above wall build up
we shall achieve a U-Value of 0.55 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.60 W/m2K for
alterations to existing buildings.
Fig. 1.11 U-wert.net Illustration of the different layers within the wall build up
Galway Mayo Institute of technology
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Calsitherm Climate Board
Fig. 1.12 Calsitherm Climate Board
Calsitherm climate board is a very good choice for insulating historic and heritage buildings
with stone masonry walls which require insulation to avoid degradation and damage while at
the same time balancing a strong thermal performance with breathability and protection
against moisture.
Calsitherm is manufactured from calcium silicate which is a micro porous rigid insulating
material which allows an existing stone wall to breathe whilst lowering the buildings energy
consumption. It is installed internally within a building, which fits in with the requirements not
to make alterations to the external façade and is made available in sheet 30mm and 50mm
in thickness. It also inhibits the spread of mould because of its high pH value.
Fig. 1.13 Calsitherm applied around an arched doorway
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The following is a list of Calsitherm’s climate board physical characteristics:
Reduced heating costs Easy to work with and install Increased value of the restored building Improvement of room climate Custom profiles available Interior insulation of existing buildings Maintain brick-, stucco- and ornamental facades with additional thermal
insulation Effective utilization of the heating system when quickly heating interior rooms
in public buildings,meeting rooms and offices Humidity control and generation of a healthy room climate in hospitals and
charitable institutions Increase in comfort and mould damage prevention Dry Bulk Density: 200 - 240 kg/m³ Thermal Conductivity: 0.066 W/mK Measured Thermal Conductivity: 0,059 W/mK
Water Vapour Transmission Rate: 6
Porosity: 90%
Proposed Wall Build up with Calsitherm inside U-wert.net calculator:
Fig. 1.14 U-wert.net U-value calculator
As we can see if we use 60mm of Calsitherm within the above wall build up we shall
achieve a U-Value of 0.57 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.60 W/m2K for
alterations to existing buildings.
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Fig. 1.15 U-wert.net Illustration of the different layers within the wall build up
Note: Lime plaster layer on the internal envelope to provide airtightness layer and
allow masonry wall to breathe
Extension Proposal:
Gutex Multitherm
Proposed Wall Build up with Gutex Multitherm inside U-wert.net calculator:
Fig. 1.16 U-wert.net U-value calculator
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As we can see if we use 130mm of Gutex Multitherm within the above wall build
up we shall achieve a U-Value of 0.26 W/m2K which falls within the TGD Part L
(2008) requirements for our external walls to achieve a U-value under 0.27
W/m2K for new buildings and extensions.
Fig. 1.17 U-wert.net Illustration of the different layers within the wall build up
Aerogel Space Loft
Proposed Wall Build up with Aerogel inside U-wert.net calculator:
Fig. 1.18 U-wert.net U-value calculator
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As we can see if we use 60mm of Aerogel Space Loft within the above floor build up
we shall achieve a U-Value of 0.244 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.27 W/m2K for new
buildings and extensions.
Fig. 1.19 U-wert.net Illustration of the different layers within the wall build up
Decided Insulations:
Existing Chapel
For the existing chapel building I have decided to use Calsitherm as the choice of
interior insulation.
Fig. 1.20 Sample of Calsitherm
Reasons for deciding upon this insulation:
Prevents the spread and growth of mould on walls which the chapel suffers
from
Enables wall to breathe preventing the build-up of moisture.
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Achieves a high performance U-value at a mere 80mm in thickness when
applied internally.
Custom profiles available as there will be a need for this option as the existing
building has many different wall profiles.
Environmentally friendly.
Improves quality of air and thermal comfort
For the extension building I have decided to use Gutex Multitherm as the choice of
insulation.
Reasons for deciding upon this:
Makes structures air-tight.
Moisture resistant due to its hydrophobic treatment.
Reduction in thermal bridging.
Provides protection against heat in summer months.
Acts as a great soundproofing material as extension is located next to a road.
Allows walls to breathe.
Cheaper than Aerogel.
Improves quality of air and thermal comfort.
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Floor and Roof Choice with calculations:
Proposed Roof Build up with Gutex Thermoflat inside U-wert.net calculator:
Fig. 1.21 U-wert.net U-value calculator
As we can see if we use 160mm of Gutex Thermoflat in our roof build up we shall
achieve a U-Value of 0.22 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.22 W/m2K for new
buildings and extensions.
Fig. 1.22 U-wert.net Illustration of the different layers within the roof build up
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Proposed Floor Build up with Gutex ThermoFloor inside U-wert.net calculator:
Fig. 1.23 U-wert.net U-value calculator
As we can see if we use 140mm Gutex Thermofloor within the above floor build up
we shall achieve a U-Value of 0.242 W/m2K which falls within the TGD Part L (2008)
requirements for our external walls to achieve a U-value under 0.25 W/m2K for new
buildings and extensions.
Fig. 1.24 U-wert.net Illustration of the different layers within the floor build up
Galway Mayo Institute of technology
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Airtightness
Airtightness is the resistance to inward or outward flowing air leakage through
unintentional leakage points through gaps and cracks in a buildings envelope. It is
influenced by the air pressure and temperature differences inside and outside of a
building. It can fluctuate accordingly to changes in the weather.
Fig. 1.25 Locations of air leakage in a building
Correct airtightness procedures and installations will remove unwanted draughts in a
building that not only affects human comfort within a building but will also remove
mould growth, condensation, rot and high moisture levels.
There are many reasons and benefits for making your structure airtight. It saves on
energy consumption to heat the building as studies show that air leakage accounts
for 50% total heat loss in leaky buildings. If you then make these buildings airtight
you will see that cost savings on the heating bills alone, this also contributes to
reduced C02 emissions created from heating systems. In a standard medium sized
office complex, the energy savings made each year in an airtight building are 700GJ
which converts to the reduction of 48 tonnes of C02.Other benefits include reduced
need for heating systems resulting in savings in running costs and plant room sizes.
To determine how airtight a building may be, you must carry out an airtightness test
using the blower door system. A door with a variable speed fan and controls is
placed around the jambs of an external open door of a building, all other external
doors and windows are shut and internal doors and windows are left open. The
operator turns it on and forces air into the building at a rate of 50 pascals and
records the current air leakage with a laptop that is connected to the blower door
sensors.
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Fig. 1.26 Blower door test setup on external door of a house
The result should achieve an airtightness of five air changes per hour at fifty pascals
or lower to be certified as being airtight and fall within the requirements of TGD Part
F (2009).
Airtightness Membranes and sealants
There are many different methods you can employ at the detail and specification
stages of your building design to promote airtightness in a building.
There are many different types of elastic and elastomeric gun applied sealants that
can be applied to movement joints in heavy structures, lightweight wall components
and joints between metals and plastics, that allow movement tolerances up to 50%.
The only drawback is that these sealants have an expected life span of 20 years and
need to be reapplied after, these are costly sealants to invest in for making your
building airtight. Service channels and route penetrations passing through floors and
walls must also be detailed to be airtight.
There are also new intelligent membranes arriving on the market with the ever
increasing need for making buildings air tight. One of the company’s that is prevalent
in Ireland promoted by Ecological Building Systems Ireland is Pro Clima which have
a range of membranes, tape seals and gun applied adhesive sealants.
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Pro Clima Intello Plus
Fig. 1.27 Intello Plus Applied tover insulation and Rafters
The most efficient air tightness membrane they have on offer is the Pro Clima Intello
Plus, it acts as both an air tightness and vapour check layer. Offers a greater
protection to all thermal insulation in walls, roofs and floors. Has a high diffusion
airtightness in the winter season and a greater diffusion openness in the summer
season. It allows for rapid drying in summer due to its low diffusion resistance. It is
very durable and is fully recyclable and has a high nail tear resistance due to its
reinforcing layer.
Pro Clima DA Membrane
Fig. 1.28 Pro Clima DA Membrane Overlapped and sealed
Is an airtighness membrane and vapour check layer for installing above roof rafter insulation and as a general vapor check layer. Provides protection against weather during the construction phases of a project and is water resistant and water proof.
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There is also a range of gun applied and tape adhesive sealants available on the
market from Pro Clima.
Orcon F
Fig. 1.29 Bead of Orcon F applied at base of Pro Clima membrane
Is a multipurpose flexible joint adhesive for interior and exterior applications, it has a
high adhesive strength on substrates, creates airtight outdoor joints for exterior
roofing refurbishments. Provides wind proof bonding of roof under lays. Has a high
resistance to humidity and on site durability as it is a solid acrylic glue.
Tescon No.1
Fig. 1.30 Tescon No.1
Is a flexible multi-purpose adhesive tape for bonding interior and exterior airtightness overlaps and joints
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It is used to create a airtight permanent seal between overlaps of membranes, roof underlays and joints between membranes and smooth surface such as OSB, Plaster boards, window frames and door frames. It also creates a sealant for service penetrations.
Tescon Profil
Fig. 1.31 Tescon Profil
Tescon Profil is used to seal angled joints and corners which is suitable for sealing around reveals at windows, doors, planed timber, corners and roof light windows. It also provides a grat protection against piercing in corners due to its strong adhesive quality.
Choices of membrane adhesive and tapes:
From my research into airtightness tapes, membranes and adhesive sealants I have come up with the choices I will be using to make my extension and existing building airtight.
Here are the following choices with reasons for doing so:
Pro Clima Intello Plus Membrane
Proclima Tescon No.1 Adhesive Tape
Orocon F adhesive Sealant
Will be used in the extension building as it provides high diffusion tightness in winter
and maximum diffusion openness in summer. It offers the solution to structures that
are difficult to protect against condensation e.g. flat roofs, which the extension
contains. It protects against the growth of mould which is prevalent in my existing
structure, which would also be of benefit to the buildings occupants. It also lasts upto
60 years and is fully recyclable.
Tescon No.1 will be used to seal joints between breaking and overlapping Intello
membranes so that there is a continuity of airtightness throughout the building. The
tape also lasts upto 60 years when applied.
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To seal Joints between Airtightness layers and substrates a bead of Orcon F will be applied to these surfaces to make them airtight with each other.
For the existing building providing an airtightness layer is not an option as the external walls are made from limestone which is suffering from moisture penetration from the rain, installing an airtightness membrane would stop the wall from breathing which it needs to do so to dry out the already penetrating moisture when it can.
It is not viable to make the external wall moisture resistant as this would alter the external fabric of the building which is not allowed from a protected structures point of view.Therefore a lime plaster mix installed internally will have to suffice to act as a airtghtness layer.
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Solar Analysis
Methodology A solar analysis was carried out using Revits Sun Path and Shadow display and settings to show how shadows were cast upon the existing structure, proposed structure and other surrounding buildings. The solar analysis consisted of setting up these views at different times of the year as well as at different times of the day as follows: March 21st @ intervals of 09:00 am - 12:00pm – 03:00pm – 06:00pm June 21st @ intervals of 09:00 am - 12:00pm – 03:00pm – 06:00pm December 21st @ intervals of 09:00 am - 12:00pm – 03:00pm – 06:00pm
These dates and times were set in the sun paths settings in revit and the location of the site was also set in revit to display the most accurate shadows upon the structures.
Fig. 1.32 Screen shot of sun settings within Revit
The shadows were then enabled in revit and plan views were taken in the 3D model space to show how these shadows were cast at the different date and time intervals.
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Fig. 1.33 Screenshot of Sun Path and Shadows
Sun Light Analysis / Shadow Study The full illustrated analysis can be viewed on the Sun Light / Shadow Study Drawing provided with this report. On the 21st of March throughout the day starting from 09:00 am the chapel overshadows the extension and the main building overshadows the chapel up until 03:00pm. It then shifts and the Northwest façade of both the chapel and extension get the benefit of the sun. By 04:30pm the chapel and extension are still benefitting from the sun. On the 21st of June throughout the day starting from 09:00 am the chapel overshadows the extension and the main building overshadows the chapel up until 03:00pm. It then shifts and the Northwest façade of both the chapel and extension get the benefit of the sun. By 04:30pm the chapel and extension are still benefitting from the sun. On the 21st of December throughout the day starting from 09:00 am throughout the day starting from 09:00 am the chapel overshadows the extension and the main building overshadows the chapel. At 03:00pm the chapel and extension are still overshadowed. By 04:30pm the chapel is benefitting from the sun and the extensions northwest façade begins to benefit from sunlight.
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Conclusion To Comply with Part L regulations of the Technical Guidance Documents I would propose to incorporate Photovoltaic Solar Panels into the extensions West Elevation Facade, this area of the building would benefit mostly from the sun’s rays and heat based on my analysis. I could also achieve this with another alternative by placing Inkjet Printed Solar Cells on to the glazing of that portion of the building which could also serve as an artistic design for the facade. The building would also benefit from heat genereated from soalr gain through the glazing and the extensions exterior fabric.
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References Photographic
Fig. 1.1 Cluain Mhuire Seminary - Killian Deveraux, Arman Barazenda
Fig. 1.2 Table 2 Elemental Heat Loss Method - TGD Part L (2008)
Fig. 1.3 West facade of existing chapel structure - Killian Deveraux, Arman Barazenda
Fig. 1.4 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.5 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.6 Aspen Aergoel Spaceloft 10mm blanket -
http://www.jetsongreen.com/images/old/6a00d8341c67ce53ef01287766b820970c-500wi.jpg
Fig. 1.7 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.8 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.9 Gutex Multitherm - http://www.ecologicalbuildingsystems.com/workspace/images/products/Multitherm_160_kl.JPG
Fig. 1.10 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.11 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.12 Calsitherm Climate Board - http://www.ecologicalbuildingsystems.com/workspace/images/products/Calsitherm-
Boards.GIF
Fig. 1.13 Calsitherm applied around an arched doorway -
http://www.ecologicalbuildingsystems.com/workspace/images/products/Calsitherm-Installation.GIF
Fig. 1.14 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.15 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.16 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.17 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.17 U-wert.net Illustration of the different layers within the wall build up - Jonathan Flanagan
Fig. 1.18 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.19 U-wert.net Illustration of the different layers within the wall build up – Jonathan Flanagan
Fig. 1.20 Sample of Calsitherm - http://markstephensarchitectss.files.wordpress.com/2014/06/img_7578.jpg?w=300&h=200
Fig. 1.21 U-wert.net U-value calculator – Jonathan Flanagan
Fig. 1.22 U-wert.net Illustration of the different layers within the roof build up - Jonathan Flanagan
Fig. 1.23 U-wert.net U-value calculator - Jonathan Flanagan
Fig. 1.24 U-wert.net Illustration of the different layers within the floor build up - Jonathan Flanagan
Fig. 1.25 Locations of air leakage in a building - http://www.energyexams.com/images/pie_chart_0000.jpg
Fig. 1.26 Blower door test setup on external door of a house -
http://upload.wikimedia.org/wikipedia/commons/d/d5/BlowerDoor.jpg
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Fig. 1.27 Intello Plus Applied tover insulation and Rafters -
http://de.proclima.com/media/gallery/INTELLO_.jpg.674x252_q95_crop_box-%5B0,%203,%20674,%20257%5D_image_id-
620.jpg
Fig. 1.28 Pro Clima DA Membrane Overlapped and sealed -https://www.isoproc.be/images/uploads/products/pro_clima/DA/pro-clima-DA-DUPLEX-regendicht-damprem-lcuhtdichting-bebording-renovatie-dak-sarking-etancheite-air-frein-vapeur-resistance-pluie-voligeage-renovation-toiture.jpg
Fig. 1.29 Bead of Orcon F applied at base of Pro Clima membrane -https://www.isoproc.be/images/uploads/products/pro_clima/Lijm/pro-clima-ORCON-lijm-luchtdichting-beton-verbinding-vloer-baan-colle-etancheite-air-sol-membrane-accordement.jpg
Fig. 1.30 Tescon No.1 -http://buildingindustry.org/bundles/brainforcefrontend/images/uploads/posts/original/images/5I/Innovations/72b375162edf45ef086a7357fb3ff204.jpg
Fig. 1.31 Tescon Profil -http://www.ecologicalbuildingsystems.com/workspace/images/products/p_tescon_profil_02_150x100_cmyk.jpg
Fig. 1.32 Screen shot of sun settings within Revit - Jonathan Flanagan
Fig. 1.33 Screenshot of Sun Path and shadows - Jonathan Flanagan