| Climate responsive building |
|4. Case studies|
The main points:
• The selection of examples is restricted to those that give interesting information and where the data are secured
• The indoor and outdoor air temperature is monitored simultaneously by the use of dry bulb thermometers
• The surface temperature is monitored in a few cases. The results are therefore sometimes less significant than expected, but nevertheless clearly illustrate the tendency.
In this chapter the thermal performance of various buildings in different climatic zones is compared, based on the indoor air temperature, which was recorded by extensive monitoring.
The building examples represent mainly built houses whose performance is monitored during their daily use, rather than abstract models or theoretical configurations. The complex situation of a house in use is therefore incorporated.
Assessment of performance
The study of these examples helps to assess the influence of construction systems on the indoor climate in quantitative terms. It provides a good idea in which range the indoor climate can be influenced. It also shows that climate control, in a purely passive way, has limits. Miracles cannot be expected: clear advantages however can be achieved.
Selection of examples
The aim was not to include as many examples as possible, but two criteria were used as a guide in the selection:
• Only examples with reliable and validated data were used.
• Only examples giving clear information, allowing conclusions to be made, were used.
Focus on air temperature
It was not an easy task to achieve reliable recording of the indoor climate in remote locations and in different climatic zones. The study was, therefore, in general, restricted to the air temperature only.
Often the air temperature does not show a very drastic difference in the performance of the system, although the difference is felt acutely by the occupants. This is due to the fact that other factors also play a significant role. To gain a comprehensive comparison, surface temperatures, air humidity and air circulation would have to be considered as well, which would require a wider and more scientific framework to the research program, which was not the purpose of this study.
The recording of the air temperature only, however, gives a clear picture of the tendency and it has to be kept in mind that the real differences are larger than the results would suggest.
List of examples and main focus
In this chapter the following examples and construction systems are studied and compared:
1. Hot-arid zone
Experiment in Ghardaia, showing the influence of night ventilation.
2. Hot-arid zone
Computer-simulations in Ghardaia, demonstrating the influence of many variables separately.
3. Hot-arid zone
Buildings in Orissa, comparing the performance of fibre concrete tiles (FCR) in single and double layers, of clay tiles, and of buildings with differing storage mass.
4. Hot-arid zone
Experiment in Cairo, comparing a well-designed mud structure with a concrete structure of very poor design.
5. Hot-arid zone
Buildings in the Dominican Republic, comparing four different roofing alternatives: corrugated iron sheeting, palm leaves, micro-concrete tiles (MCR) and a brick vault.
6. Temperate zone
Buildings in Kathmandu: houses of good quality, making proper use of the sun’s radiation, compared to poorly designed "concrete box" type houses. Also the effect of a passive solar floor heating system is described.
7. Temperate zone
Buildings in New Delhi, India; well-designed mud structures compared to well-designed conventional concrete/brick structures; and comparing fibre concrete roofing (FCR) and asbestos roofing.
8. Temperate zone
A possible solution for a movable louvre system, which can be manufactured in local workshops without sophisticated equipment.
Mountain hut in Langtang National Park, Nepal: a rather sophisticated trial with a solar wall in a difficult and remote situation, under high-alpine conditions.
No example in warm-humid zone
In the warm humid zone the air temperature is rather even throughout the day and throughout the seasons. The indoor air temperature thus hardly fluctuates at all. The main objective of adapted construction is to improve the climate by proper air circulation and its influence is, therefore, difficult to assess. Recording the indoor temperature provides little information. This is the main reason why this zone is not represented by an example.