Communication in engineering

CCOM 206

Affordable housing solutions for

underprivileged and remote communities.

Stasik Nemirovsky

McGill Faculty of Engineering

June 26th, 2017

Abstract

Although technology has made some great advancements in past centuries, significant portions of the

earth’s population are still struggling to achieve a safe place to call home. The reasons for that vary;

Natural disasters, political issues forcing people to flee their homes or simply lack of resources and

capital. The following research paper explores some of the presently available solutions that intend to

provide people with safe and affordable housing solutions. While there are many solutions available,

this research will focus on three alternatives: Earthbag construction, Geodesic domes and 3D printed

houses. The different solutions are evaluated based on their durability, costs and availability.

From my point of view, providing under-privileged communities with safe and affordable housing

solutions is not only a challenging engineering task, but also our duty as a society to ensure everyone’s

right for basic living standards. While all the solutions presented in this paper are viable solutions,

following the analysis below, I found that geodesic domes standout thanks to their strength, low cost,

ease of construction and versatility.

1. Introduction

In contrast to what most of us may think, with a rapid growth in the world population, safe housing

solutions are currently under greater demand than ever before. In fact, the shortage is so significant,

that India alone is facing a shortage of 17.6 million houses [1]. Although technology revealed some great

advancements in the construction industry, significant portions of the earth’s population are still

struggling to achieve a safe place to call home. The reasons vary from political issues that force people

out of their homes to simply lack of resources or capital.

In recent years, many fascinating technologies have been introduced to solve the problem of affordable

housing. In the following research paper, I am exploring some of the presently available solutions that

intend to provide people with safe and affordable housing solutions. Although there are many

alternatives available, In this paper I focus mainly on three solutions: Earthbag construction, Geodesic

domes and 3D printed houses. In addition to analyzing different aspects of each method, I will try to

conclude on the current best method to solve the problem, based on its durability, costs and availability.

2. Background

The global shortage in housing is not a new concern. Governments and non-profit organizations around

the world have been trying to deliver sustainable solutions throughout countless past and ongoing

endeavors. Unfortunately, in spite of all efforts, shortage in housing is still a present concern due to

several factors:

• Exponential population growth – especially in developing countries.

• Natural disasters.

• Refugees due to political and armed conflicts.

• General poverty and luck of resources in third world countries.

One of the key elements in achieving a sustainable solution is the development of affordable and safe

housing solutions, while considering the unique set of climate and resources available at different

locations on the globe.

A few of these suggested solutions are the following:

2.1 Earthbag construction:

As stated by Canadell, Blanco and Cavalaro, “Among the possible materials for the construction of such

shelters, the most abundant regardless of the location is the earth or soil available in the environment”

[2]. Since ancient times, when a community was in need of housing solutions it was intuitive to utilize

the locally available materials. The Earthbag construction technique was developed in this context.

This method of construction uses degradable bags, filled with locally available soil and sometimes

binding elements, to form livable spaces by stacking them together [2]. Earthbag houses can take

different shapes and sizes with some structural limitations.

In recent years, with the development of

customized bags and house plans, the

construction of such houses has spread

around the world. One key influencer in this

field, which made a significant contribution

to the design aspect, is the Iranian architect

Nader Khalili [2].

“They (Earthbag houses) represent

sustainable, rapid and low-cost alternatives

for the construction of social housing,

emergency shelter and ecovillages with the

resources available at each

location.[2,p.270]”

Figure 1 - Earthbag shelter in the making. http://www.theshelterblog.com/wp-content/uploads/2014/07/earthbag-house-roof-framing.jpg

2.2 Geodesic domes:

Geodesic domes were introduced as an alternative housing solution in the mid 20th century. The

majority of their development is associated with the work of the inventor Richard Buckminster Fuller

who obtained several patents regarding the design of geodesic domes [3]. The Geodesic dome, as its

name may give away, is a structure shaped as half a sphere consisting of a uniform framework of

intersecting great circles [3].

The unique geometry of the framework and the

spherical shape, introduce significant benefits

both from an engineering and cost-efficiency

point of view. In addition, recent complementary

designs of joint solutions have simplified the

construction of such domes, to allow for quick

erection and self-labour (citation).

2.3 3D Printed houses:

3D printing is one of the fastest growing technologies in the past few decades [4]. Many of us may not

know but, in fact, as Hager states, “The first 3D printer was invented in 1984” [4]. This technology uses

different materials to construct 3D objects mostly through extrusion, but not only. For most of us, 3D

printing is associated with small-scale, toy-like models, but recent advancements in the field have

introduced some exciting ambitions. Although the use of 3D printing technology for the construction of

houses have not reached yet to a fully commercialized stage, the Chinese company WinSun Decoration

Design Engineering Co built the first

3d printed house in 2014 [4].

3D printing construction, once fully

commercialized, is expected to

reduce the costs of construction and

the construction time.

Figure 2 – Geodesic dome framework. http://i2.wp.com/ultramoderntinyhouse.files.wordpress.com/2016/02/what-about-a-dome18.jpg?w=1040

Figure 3 - 3D printed house in progress. http://assets.inhabitat.com/wp-content/blogs.dir/1/files/2017/03/Apis-Cor-3D-Printing-Construction-889x432.jpg

3. Analysis

3.1 Earthbag construction:

In fact, similar methods have been widely used in militaries around the world for construction

and reinforcement of bunkers. Beside its ability to absorb high-energy impacts, earthbag

construction features tremendous rigidity and durability. As a proof, based on experimental

studies regarding structures under static and dynamic loads, this construction method is now

recognized and approved in california, with some restrictions on structure dimensions [2]. In

addition to its durability, earthbag construction is also very low on costs. If we disregard the

labour hours, which may apply to most cases as the simplicity of the method allows for self-

building, the main structural cost remains the degradable bags. The appropriate bags are sold

for as low as 30 cents per bag, according to “New Mexico Dirtbags” company. Once the soil and

binder are fully compressed and cured, a process which may take a few days [2], the actual bags

stop from playing a structural roll and that, as a result, eliminates any future need to replace

them. That essentially decreases the cost of maintanence on such structures to zero. Apart

from that, as for availability, the greatest advantage of earthbag construction, is the fact that it

could be used absolutely anywhere on this planet. Even though soils differ depending on

location, simple binding additives such as clay can be added to the mixture to compensate for

lack of stickiness [2].

3.2 Geodesic domes:

Since their early development in the 50’s and 60’s of the 20’s century, geodesic domes have

proven to be exceptionally strong structures. According to Balbaert, “Domes are mostly made

of triangular pieces, distributing evenly the forces applied to the structure, and have a high

strength-to weight ratio” [3]. Whether built with timber or metal framework, domes are

extremely strong, mostly thanks to their unique geometry. In addition, he states, “this means

that a strong structure can be obtained with a small amount of materials, building a dome can

lead to 40 % savings in materials” [3]. Considering that, as a result, costs of construction are

generally lower when compared to conventional housing. Using pre-fabrication methods also

allow for quick assembly, which then reduces the labor hours required as well. On top of all

that, thanks to its unique geometry, the ratio of surface area vs. living area makes the geodesic

domes energy efficiency. “Due to its shape, the ventilation is more efficient and the heating has

less losses. Geodesic domes are able to save up to 50 % on energy costs compared with other

structural shapes with the same volume” [3]. When considering maintenance, the modular

nature of the structure also allows easy access to make any structural repairs or replacement of

damaged beams, if ever needed. As a result, costs of maintenance minimized extremely. As for

availability, although geodesic domes may seem to be complicated to build, recently developed

structural joint designs are now available at low costs and can make the construction process

very quick and simple. With the use of simple power tools, geodesic domes can be easily self-

built [4] anywhere where wooden beams are available. The choice for external covering

depends on different aspects such as weather and space designation, but can generally be

flexible, considering the locally available resources.

3.3 3D printed houses:

As a relatively new technology, there are still many ongoing improvements to the

implementation of this technology. Up until today, 3D printed houses were using either

concrete or similar mixes to construct the foundations and framework of a house [5].

Therefore, the expected durability of such houses is similar to conventional modern concrete

houses. One of the main advantages of this method is the fact that materials waste is

significantly minimized which leads to costs saving as well as smaller environmental footprint.

Another cost-effective aspect of such technology is the mobility of the printer. According to

Hager, “Mobility of the printer is considered as the main advantage as it may be transported all

over the world, thanks to what, a cost of transport of the material and its storage on a building

site will probably disappear” [5]. 3D printing also eliminates much of the required work force

for construction, which can be also seen as an economical benefit. Other than that, in the

future, as printers become more widely used, they can be transported to different locations

and help out communities around the world in constructing their future.

4. Conclusions:

All three alternatives may seem as a good alternatives as part of a global solution to the

housing shortage crisis. However, as the shortage keeps growing, it seems that in order to solve

the problem in an efficient way, a quick self-built allowing technology should be implemented.

If communities in need could have been provided with pre-fabricated kits, or the appropriate

facilities to make those, we could then tackle the world-wide shortage simultaneously and

catch up. The way I see it, pre-fabrication is a key factor in a successful solution delivery, as it

allows for high volume production and relatively simple and quick construction process, on site.

As many underprivileged communities may be lacking the appropriate logistics, pre-fabrication

is an elegant way around it that could also create local jobs for low-skilled workers.

As a conclusion, I am strongly advising of implementing the geodesic domes alternative on a

global scale. The domes could be easily pre-fabricated with low-technology and then quickly

installed on site. This will allow for high volume construction in a short period of time, that

could be performed with very simple logistics and local manpower. The domes also feature high

energy- efficiency, which is important when looking for a sustainable solution that will serve

those communities for the long run.

References:

[1] V. W. Y. Tam, "Cost effectiveness of using low cost housing technologies in construction," in 12th East Asia-Pacific Conference on Structural Engineering and Construction, EASEC12, January 26, 2011 - January 28, 2011, Hong Kong, Hong kong, 2011, pp. 156-160.

[2] S. Canadell, A. Blanco, and S. H. P. Cavalaro, "Comprehensive design method for earthbag and

superadobe structures," Materials & Design, vol. 96, pp. 270-282, 4/15/ 2016. [3] J. Balbaert, J. Park, R. Marimon, A. Serfozo, M. Cazelles, S. C. Domenic, et al., "Design of

sustainable domes in the context of EPS@ISEP," in 4th International Conference on Technological Ecosystem for Enhancing Multiculturality, TEEM 2016, November 2, 2016 - November 4, 2016, Salamanca, Spain, 2016, pp. 105-112

[4] J. C. Bohlen, "GEODESIC-DOME HOUSES USING TIMBER TECHNIQUES," Building Research & Practice, vol. 2, pp. 106-111, 1974.

[5] I. Hager, A. Golonka, and R. Putanowicz, "3D printing of buildings and building components as the future of sustainable construction?," Procedia Engineering, vol. 151, pp. 292-9, / 2016.