The HiLoTec Project
The HiLoTec Project was carried out by University of Minho, Portugal, and Mota-Engil S.A. Construction Group, between 2009 and 2013.
Sustainability and low cost housing were the main objectives for the HiLoTec project. The project aims at developing a simple and innovative construction technology for the sustainable self-construction of small buildings in developing countries with seismic hazard.
The construction technology combines both natural and tradition building materials with more advanced construction techniques.
The country which was chosen for the case study was Malawi due to its demographic and socio-economic characteristics as well as for the interest shown by governmental and non-governmental institutions.
The project main phases were the following:
(1) Choosing a target country for the case study;
(2) Reconnaissance visit of Malawi;
(3) Gathering of information from Malawi (uncluding soil samples from Malawi);
(4) Architectural and structural studies;
(5) Construction technique developement;
(6) Thermal performance studies;
(7) Proposal of new Compresed Earth Block with interlocking;
(8) Production of blocks for testing;
(9) Material and structural testing;
(10) Final arquitectural and structural design;
(11) Project dissimination.
The first phase of the project, held between October 2009 and March 2010, aimed to assess local Malawi conditions for the development of the HiLoTec solution and collect the following specific information of the country:
- Available construction materials
- Architectural legacies
- Types of organization of territory
- Available labour skills
- Characteristics of local industry
- Media communications;
- Transport and energy resources
- Building construction know-how
- Needs and expectations of the target population
The second phase compromise the analysis of Malawi soils, the study of new stabilized earth mixtures, an architectural study intended to define the needs and conventional building characteristics in Malawi and the study of new constructive systems, including the seismic structural behaviour. This phase also includes the adoption of this new solution to the socio-cultural needs and functional requirements. The target population is rural and city families of lower incomes, which seek for better houses.
On the final stage, a real dry stack ICEB house was study tested on a shaking table (in an earthquake scenario). This type of test is considered to achieve the most representative results of the behaviour of structures under earthquake loading in a laboratory environment. The construction of the mock-up took 24 days and the resulting house has an appealing look even without render. In general, the construction of the mock up was considered a success.
During the shaking table test the maximum measured peak ground acceleration (PGA) reached a value 1.8 times higher than the most severe case studied of a magnitude close to 6.5 for Malawi. It can be concluded that the mock up had reserve strength for the maximum expected PGA of Malawi.
The knowledge gained in the all phases of HiLoTec project was used to produce a construction manual of ICEB houses. The production of the manual was a collaboration between the University of Minho team, the Mota-Engil S.A. team and an external designer. In this manual, each construction step, from the soil selection to the production of CEBs and from the foundations up to the installation of the roof has been covered. Although the manual uses graphical mediums and minimalistic text content to make it understandable for self-construction.
University of Minho and Mota-Engil S.A. wishes that this manual will bring to the world a higher living standard for those who will construct the HiLoTec houses, bearing in mind that construction sustainability and the social responsibility will always be part of human kind development.