Architecture and design are usually seen as the creation of something new, but renovating existing buildings is also a way for architects to impact the built environment. Renovating, rather than building something new, is a way to reduce environmental impacts of construction and to reduce costs, which is especially important in low-cost development projects funded by donors. In 2019-2020 I learned this while working for architectural NGO C-re-aid and managing the renovation of two primary schools in the village of Shimbwe, just north of Moshi in Northern Tanzania. Our goal was not just to repair the old, but rather to improve it and to create something new through better design using sustainable building techniques. The school renovations were made possible by a donation from Child & Family Foundation from Austria and with help from volunteer groups of Belgian construction students.
Need for school renovations in rural Tanzania
Shimbwe village has four primary schools, out of which C-re-aid renovated two. Shimbwe Chini Primary School was built in 1948 and Sia Shimbwe Primary School in 1975, and both had more than 200 students trying to learn in a deteriorating environment. The roof sheets were leaking and the timber infested with termites, the floors had deteriorated so much they were impossible to keep clean, and the walls had cracks and were covered in dirty paint that was falling off. During rains, the classrooms were also cold because they lacked ceilings and window glass.
Both schools are government schools, but getting money from the Tanzanian government to do renovation works is difficult and slow. The construction of a teachers’ house in Sia Shimbwe had already been ongoing for 15 years but was still not complete. At Shimbwe Chini the school had tried to raise funds for the renovation works among the villagers, but was unsuccessful.
The school buildings also had structural issues, mainly ones caused by soil erosion. Shimbwe is located on the lower slopes of Mount Kilimanjaro, and the sloping landscape combined with a wet climate and heavy rains causes soil erosion on one side and soil accumulation on the other side of the buildings. The school buildings had no rainwater management systems like gutters or drains, and the foundations were not strong or deep enough to handle being exposed after the soil had started to erode away, which was causing cracks in the walls. Lack of water management was also making the sloped and muddy environment unsafe for the children.
The focus of the school renovations was the classrooms, but we also renovated the other school buildings, including toilets, offices, teacher’s houses and a dining room at Shimbwe Chini. The school kitchens were one aspect that we immediately identified as needing to be completely redone and redesigned. Both schools only had a temporary, very smoky kitchen in a closed wooden room with hardly any ventilation. The cooks were cooking on the ground on top of three bricks using firewood. This method of cooking is not only uncomfortable and unhealthy for the cooks, but also uses a lot of wood, creates a lot of smoke, and has a high risk of fire.
It was important for us to discuss with the schools to understand their priorities. Most of the teachers were not from Shimbwe but had been sent to work at the school by the government. To have housing for these teachers is important, so that teachers report to school on time each morning. Shimbwe Chini and Sia Shimbwe schools both had two houses for the teachers, but these houses lacked electricity and plumbing, and one of the houses in Shimbwe Chini was already old and deteriorated, while one of the houses in Sia Shimbwe was still unfinished. As a result, teachers were often absent and it was difficult to find enough teachers willing to work at the schools. If there is no teacher, a classroom is of no use, and so we also renovated the teachers’ houses and installed electricity and water.
Promoting sustainable construction materials and techniques
C-re-aid is dedicated to promoting sustainable and ecological building materials and techniques in Tanzania. Hence, reducing the environmental impact of the school renovations – including reducing the use of cement and amount of waste created – was one of our goals. Since 2012, C-re-aid has researched and experimented with various sustainable building techniques and assessed their suitability to the Tanzanian context, including rammed earth, earthbags and recycled waste.
Over the last few years, the main building technique C-re-aid has been promoting is compressed earth blocks or CEBs. These blocks are made by compressing a mixture of earth and sand into a brick using a special machine, in our case a manual one. A small amount of cement or lime is usually added in order to make the blocks water-resistant. At Shimbwe Chini Primary School we rebuilt some badly cracked walls using CEBs that we produced on site, reducing the need to buy and transport materials.
At Shimbwe Chini we also built a new toilet block using CEBs, since the old toilet was too small. There is no sewage system in Shimbwe and toilets only have a simple pit where the waste accumulates, which leads to maintenance issues once the pit is full. Previous toilets at the school had simply been taken down when the pit was full and a new toilet built elsewhere. Building new toilets regularly requires funds, and the reason the school currently didn’t have enough toilets was that they had run out of funds while building the new toilet block. Our solution was to build a double pit composting toilet where one pit is designed to be used for five years. When the first pit is full the users switch to using the other pit, and movable squat pans facilitate an easy changeover. During the next five years the second pit is also filled, but meanwhile the waste in the first pit has time to compost and essentially become soil. The first pit can then be safely emptied even manually and the school can switch back to using this pit. The pit can also be emptied by a truck if the funds are available.
We also tried to reduce the environmental impact of the school renovations by using lime instead of cement plaster for the new CEB walls in the classroom and for playground earthbag benches. For the new toilet block and dining room at Shimbwe Chini we also experimented with using limewash as a low-cost alternative to paint. We mixed pigment with the limewash in order to create more color and linseed oil in order to create a dirt and water-repellent surface. The finishing created by the limewash is not as smooth as on the walls painted with regular paint and we could only use a couple different colors, but I believe the limewash can age better than the paint on which any dirt – of which there is a lot in a primary school – clearly stands out.
Reuse of old materials
An important aspect of reducing the environmental impact of construction is making use of what is existing. Renovating instead of building a new school is an important aspect of sustainability, because this prolongs the lifespan of the building. Throughout the school renovations, we found many ways of reusing old building materials, including reusing old but good quality roof sheets from classrooms to cover verandahs, repairing and reusing wooden classroom doors in toilets, and reusing stones and bricks from old foundations and demolished buildings for new foundations and verandahs. This approach not only reduced the waste created, but it also made it possible for us to have a greater impact with the same budget.
Reuse is very common in Tanzania, where people use old materials to reduce costs. These constructions often end up looking temporary and unstable, but what we wanted to show in Shimbwe was that with some good repairs and design, reuse can also create beautiful results. One example of reuse in the school renovations is the dining room at Shimbwe Chini Primary School.
The dining room previously had largely open walls that were good for ventilation, but the wooden frame covering these openings was damaged and didn’t provide enough security. Meanwhile, one of the classroom blocks had large wooden windows that were also damaged but made of very strong wood. When we placed new steel windows in the classrooms, we took the old wooden windows, and using pieces from the worst windows it was possible to restore some of the better ones. We then used these restored windows to close the openings in the dining room wall in a new creative way. With some additional wood filler and paint, the windows and the dining room were completely transformed.
At Shimbwe Chini Primary School we also built a new playground using almost exclusively recycled materials. The main element was three earthbag benches that could also be used as an outdoor classroom. We also built swings and a hopscotch track out of old tires, and a slide and tipiis using recycled wood from old doors and roofs.
Improving the learning environment through school renovations
Throughout the two school renovations in Shimbwe, we wanted to use design as a tool to improve the school environment, not just to repair what was existing. As an addition to the classrooms, we designed and built new verandahs that make the environment more pleasant during the frequent rains, reduce the amount of mud in classrooms, and in Sia Shimbwe also provides outdoor seating. Meanwhile, the new doors and windows we installed are more durable and provide better security while being also a design element.
Another new space we designed and built in both schools is the kitchen. In both schools we designed the new kitchen to be open with only store rooms closed, which not only creates a healthier cooking environment with more ventilation, but also reduced building costs. In both schools we also built a type of Lorena rocket stove that is designed to fit the pots used by the school and that uses less firewood and creates less smoke.
But the most important aspect of the school renovations was of course the classrooms. Repairing leaking roofs and broken floors was a priority, as was installing electricity and new window glass in order to make the classrooms more comfortable during cold and cloudy weather. We also repaired broken desks and made some new furniture, including teacher’s tables and chairs. New paint with plenty of colors finishes it all and gives the schools a new look. Both schools are still missing nursery classrooms and ceilings, so there is more work to do when the funds are available. But meanwhile, the primary school students of Shimbwe Chini and Sia Shimbwe can continue their education in a healthier, more comfortable and more inspiring learning environment.
