Built Environment

Overview

Traditional Bunong houses are circular, narrow and tall with thatched roofs, however the houses in Pu Ngaol are more similar to a traditional rural Khmer Cambodian house. These are built square or slightly rectangular, almost entirely of wood and a corrugated tin roof. There is sometimes a balcony platform or an area underneath to sit outside. Half the space in the homes are open, for families to sleep and sometimes cook all in the one area. Traditional houses in Cambodia are built on raised stilts with access via stairs or ladders, to protect them from flooding in the wet season and allow wind to pass underneath that creates a natural cooling effect. 

Wood is the most common material used in rural construction, particularly houses, fences for livestock and handicrafts. Concrete is rare in Pu Ngaol and more common in cities, where the Mekong and other rivers are dredged for their river bed sand to mix into concrete. Sometimes concrete or clay fired bricks are used in rural areas for more expensive houses for a modern look in combination with wood. Timber in the forest is cut using diesel powered chainsaws around 10-20 km away from the village. Buffalo carts or a walking tractor are used to take the timber back to the village. In the past there used to be a saw mill but it was closed due to the crackdown on illegal logging.

Carpenters and builders in rural areas like Pu Ngaol are not formally trained, but have learnt skills from older generations with skills in the village. Skilled community members will volunteer their time and coordinate the construction of any new homes, even if the home is not theirs. For smaller houses, skilled people are not hired and the community members work together. Skilled people are typically hired for larger buildings, often from the surrounding villages or from Vietnam. 

Current situation

There are 108 houses in Pu Ngaol. Houses are not close together and will have their own outdoor space for farming managed by the family. Two or three generations of the same family commonly live in the same home. 

Pu Ngaol’s Community Meeting Hall is an open plan, concrete structure with a corrugated iron roof, and a squat toilet facility connected to a septic tank. Wire mesh is in place of the windows to allow air flow throughout the space. The closest medical centre is in Toul Village. The Memang Primary School was rebuilt in 2018. It is made from concrete and hosts three classrooms, and a squat toilet and handwashing facility. Holes in the upper walls are a common feature of concrete buildings in Cambodia as a no cost cooling feature, allowing natural air flow and heat  to escape. These outlets are angled downwards to prevent rainwater from entering the classroom. Metal grates are in place of the windows to allow similar cooling air flow, while keeping the classroom secure.

Older buildings made from harder wood are in good condition, however, the availability of hard wood from the forests have been in decline. Newer structures made from softer wood are more vulnerable to termites. Some buildings in the village have concrete bases beneath each wooden stilt to reduce the risk of termites. Termites will also target bamboo. Bamboo is fast growing and community members generally cut older bamboo during a week-long period during the moon cycle when the bamboo is stronger and the sugar content is at its lowest. The bamboo is then soaked in water and mud for a week to 20 days before being used in construction or scaffolding. The bamboo typically grows close to homes in the village, however, is becoming less available due to overuse or clearing to make room for farming.

Projects

11 Alternative building materials and designs?

Residents of Pu Ngaol have traditionally used methods to produce their built environment, which have been optimised over generations to suit the situation and environment. Rapid change in land use, access to materials, technology and climate may have made traditional methods less suitable. Can you think of methods to upskill and implement new approaches to the built environment that are culturally appropriate?

12. More resilient buildings

Excessive logging has made sourcing building materials more difficult and has environmental consequences and not all residents of Pu Ngaol have building skills. Additionally, termites in Pu Ngaol pose a threat to houses and buildings made from wood and bamboo. What ideas can you come up with to develop more resilient and lower maintenance structures while considering cost and locally sourced materials? 

13. Safe and accessible river

The Ou Te River  that runs through Pu Ngaol is essential for community livelihoods, however, rising and falling water levels are often unpredictable and dangerous. What ideas can you come up with to improve safe access to the river all year?

14. Heating and cooling buildings

Pu Ngaol has a hot and humid climate throughout the year. Traditional methods of passive cooling are becoming less effective as the dry season is also growing longer and hotter due to the impacts of the climate emergency. Can you come up with any ideas to build on the low cost heating and cooling solutions for climate resilient buildings in Pu Ngaol?