EcoHouse Research

Jonathan Willis (MEng, 2012)

 

This study examines the operations of TECHO as they work towards their vision of a Latin America without poverty. Initial research was carried out in Ecuador to gain an understanding of the main programme that they implement: the construction of transitional shelters for those who are without a safe and secure home. Social surveys, structural assessments of existing shelters and participation in the construction of transitional shelters provided key insights into the constraints of the programme.

 

In response to these findings, further investigations have been carried out at both the micro and macro levels: looking at the design of the transitional shelter as well as whether it is feasible to provide them on a global scale.

The transitional shelters take the form of single-room occupancies using open-frame timber construction techniques. The main components are made from softwood timber, wood-based panels and corrugated galvanised steel sheets, all of which are effectively exposed to external environmental conditions. The particleboard currently used for sheathing in Ecuador is not graded, and therefore the exact strength of the shelter design is unknown. Due to the fact that limited types of panel are allowed to be used in external conditions, experimental tests were carried out to assess the reduction in strength under varying moisture contents for a range of wood-panels: three of these were graded using the European Standards employed in the UK and the final samples were MDP brought back from Ecuador. Additional research was also carried out into the relative joint strengths that are possible when using different fastener types in wood-panels. From these tests recommendations can be made with a view to replacing the particleboard that is currently used with plywood. Guidance can also be provided with regard to ensuring that future material selection utilises sources of graded material.

 

In order to assess whether this programme can feasibly be implemented at a global scale, models for population growth and poverty levels were used to predict annual construction rates. It was assumed that transitional shelters would be required to house all those living under the $2.00 poverty line. The quantities of timber required for these shelters could then be assessed relative to models of roundwood production based on historical levels. It was found that at most a 3% increase in the production of wood-panels was required, and these increases fall away over the course of the projections until 2050, when the population is expected to be close to its peak at around 9 billion people.

 

As well as evaluating the production requirements that would be needed, current forest sustainability was considered by examining the changes in forest area and growing stock. Despite reductions in forest area globally, the total growing stock - and therefore available roundwood - is increasing. By also considering the fact that the recent global focus on sustainability and environmental impact has ensured that policies are put in place for the protection of forests, it is likely that in the future the prospects of a truly sustainable timber supply are good.