Elementary School
Darmang, Ghana

The village of Damang, located 50 kilometers north of Accra, resembles many other villages in Ghana. In 2014, the village chiefs and the NGO VPWA recognized the need for a new school to improve the educational situation, as many children were not attending school and the existing one was overcrowded. Since 2007, the Volunteer Partnership for West Africa has been active in the eastern region of Ghana, and has already implemented various projects such as a youth center since 2011 and a street library for surrounding villages.

The construction of the new school building aims to strengthen VPWA’s commitment and improve support for the local community. At that time, the public village school was in need of renovation and had too many students. Another school, privately run, was also overcrowded and was in inadequate space, that didn´t even had partitions between classrooms. The project program established by the local organization and our future partners consisted of building a kindergarten, a primary and a secondary school as well as toilets.

Our involvement in the project began coincidentally, when the director of VPWA asked a former volunteer for support in the school project. Originally, it was about architectural assistance and fundraising, but this led to the establishment of the We-Building association in order to apply for funding. This initial collaboration was a significant learning experience for us. In development cooperation, there are many relevant factors, such as communication with local partners, needs assessment, research and fundraising. However, this presentation mainly focuses on construction and design aspects.

It was a large, empty, vegetation-rich plot, which slopes gently and rises from the road. This new building was intended to complement the existing youth center which is only 100 meters away. It is located at the end of the village and has a very typical jungle-like environment. The village serves as a center for numerous smaller communities that are about a half-hour walk away.

The surrounding villages are very poor and a lot is built with clay, since such constructions are cheap for the community itself. These buildings are very simply constructed, they require many repairs over time and have a short lifespan overall. They are not even built to last. These are some of the reasons why earthen construction, although very prevalent, is viewed by the local people as something associated with poverty. Here you can see the execution and the inadequate protection against rain, which is crucial when building with earth.

In this case, the earth is washed away over time and thus also the protection of the wooden structure, which serves as reinforcement. The usual construction method with cement blocks and concrete is considered the standard for new buildings and this is how most people envision a new building. The approaches that offer sustainable or design-oriented alternatives face numerous challenges. Earthen construction is deeply rooted in Ghana, as shown by the mosque in Larabanga, built in the 15th century.

Despite maintenance and restoration, it still stands and testifies to Ghana’s long tradition of earthen construction. The basic idea was to deviate from the typical longitudinal school form, which can be found in almost all school buildings in the region, and to try to develop a concept that would be more suitable for elementary school children. The lot was large enough and there was enough space to experiment a little. We started with a typical floor plan and then broke it down into its basic elements, the classrooms.

Now that we had basic elements, we could try out different concepts, create different spaces and see what is feasible within the proposed program. The planned complex is to consist of 12-15 identical units 7×7 meters, arranged around courtyards with one unit per age group. This modular concept allows for flexibility, phased construction, and adjustments without changing the concept and creates an atmosphere similar to a small town instead of a typical school. As expected, there were changes in the final site plan.

The toilet building was slightly shifted, the program and future plans were slightly modified. The core idea of the individual units, which form smaller courtyards, has remained. The project was planned in phases and to begin with six classrooms for the elementary school, with the option for expansion in a few years. It is essential, to consider the future development of the project and possibilities for different future scenarios to keep open, even if these ultimately deviate from the original plans.

After agreeing on the concept, we found that a very similar construction style and room layout is widespread in the Ghana, Togo und Benin regions. The typical compounds allow multiple households to share a courtyard. This typology is flexible, it allows for the construction of buildings as new needs arise and makes the courtyard the central living space. Smaller units could more easily adapt to the sloped terrain, and since all classrooms were identical, the construction should be streamlined, so that the workers could repeat the process and master it through repetitions.

Another advantage of this circular principle is that it allows the use of classrooms as part of the outer enclosure, which can significantly reduce their overall length and costs. As for costs and resources, there is not much difference between a classroom wall and a fence wall, and that can be a major burden on the financing of the entire project. These were the final plans.

In addition to the central courtyard in the middle, the smaller entrance areas were another important component of the design, providing a different sense of scale and a gradation of spaces. The classroom itself has a floor plan of 7×7 meters with windows on both sides, which allow for cross ventilation and another very important design element, namely the roof opening, through which the lighter hot air can escape. All of this, along with the fact that the classrooms do not have a suspended ceiling -which increases the overall volume of the space- led to a much better microclimate in the room and to a much better learning environment for the students.

Another aspect, that improved the breathability of the classrooms and reduced cement consumption, was the introduction of stabilized, compressed earth blocks. These clay blocks are a good alternative to the commonly used cement blocks. They are made from a mixture of earth and clay, which in this case is stabilized with cement. They were first introduced in the 1950s in South America as a somewhat more modern adobe construction technique. The production of the blocks is labor-intensive and requires machines to press them.

The characteristic holes improve stability, by allowing for interlocking during installation. Additionally, installations and pipes can be accommodated through the holes, without breaking walls and adding reinforcements like steel, bamboo or concrete for additional structural stability. The decision to use material was made after we contacted Samuel, who produced his blocks only half an hour away from the construction site. His goal was to produce these blocks locally and receive more orders. The blocks are more sustainable, comparable in price to common cement blocks, and allow for faster construction.

The clay bricks are relatively easy to assemble and they can be stacked almost like Lego bricks. After the completion of a wall, the joints are filled with a mud based on earth and can either remain as they are or be painted with various coatings to be protected against rain.

Theoretically, the blocks can be used as a load-bearing wall system, using the holes for reinforcement and the U-shaped blocks for the beams. But this is more intended for residential construction, where the rooms are smaller. In this case, due to the sloped terrain, the seven-meter span of the classroom walls and a somewhat complex roof structure, it was decided to use a concrete frame system as the main load-bearing structure. All non-load-bearing walls were made with compressed earth blocks.

The plot had an average slope of 10%, even steeper in the back part of the lot, so that the construction area was closer to the street. Even with small buildings, this meant that there were height differences of almost one meter from one diagonal corner to the other. Construction began in September 2017, to take advantage of the majority of the dry season and had an expected duration of six months. The site was cleared of vegetation and the positions of the buildings marked- a task in which local children also helped.

Due to the different orientation of each classroom, we had to determine each point using triangulation with three measuring tapes. Excavation, the most labor-intensive part of the construction, has begun. Once the foundation trenches were dug, work could begin on the formwork for the concrete columns. The contractor suggested the use of modular plastic formwork, which was a great idea. Basically, this eliminates the need for a wood formwork, which on average can only used twice before it becomes unusable.

The plastic elements can be maintained properly and can be used multiple times. Regarding the budgeting, the price was comparable to the usual use of wood, since the equipment had to be rented. Nevertheless, this is a much more sustainable construction method, as it saves wood and provides a high-quality aesthetic. Additional plastering of the final surface becomes unnecessary, provided the concrete is sufficiently compacted. These elements can be used for all modular elements, usually for supports, as in this case, or for walls.

If they are available, the only drawback is that trained team members are necessary. The foundation walls are currently being completed. All underground elements are built with cement blocks. Here you can see, how to achieve a good-looking exposed concrete using plastic formwork, which does not need any additional plaster. When the bearing level was reached, plastic formwork was to be used, so instead of the classic formwork with so-called Mary boards, a high-quality exterior surface could be achieved.

The load-bearing concrete skeleton construction is visible here with supports and beams before the walls are installed. The above-ground volume of the concrete used is not very high, as you can see. Most of the cement consumption occurs underground and in the foundation slab, so in elements for which there are not many alternatives outside of cement concrete. The next phase is the roof. The small roof model has been built, to better communicate with the carpenters.

There were no misunderstandings, especially since carpenters are usually the most skilled workers on a typical construction site. The wood was of very high quality and the work speed was impressive. Within a few days, a complete roof structure could be erected in front of a classroom. Due to the roof opening and the overall concept, the roof construction was more complex than usual, and particularly the large roof trusses are made with more wooden elements than the usual local standard would be.

This was a conscious decision, to improve the quality of the construction, especially because in this design the roof structure is meant to remain visible and not be hidden behind a suspended ceiling. The sealing in such projects is often not done at all and, in our case, only a layer of thicker plastic was used. While this is not a substitute for proper sealing, it is better than nothing. In the tropical climate, with a lot of rain, but faster drying and without freezing temperatures, moisture is less of a problem than in continental climate zones.

Pouring the concrete slab is the next step. This is where most of the concrete is consumed. The slab itself consists of almost 8 m3 of concrete, all other elements are about 5 m3. Unfortunately, in the interest of hygiene and an easily cleanable floor in public buildings, there are no real alternatives to concrete. The earth blocks are delivered to the site and the construction work begins.

It goes quite quickly. They are basically stacked on top of each other and the only thing that still needs to be done is to connect them to the load-bearing structures and occasionally reinforce them with steel and concrete, which goes through the block holes. Once the classroom walls are up, you can get a better impression of how the whole thing will look in the end. In parallel, the roof structure and the ceiling are being completed.

Special attention was given to the aspect of sound insulation and the execution of the ceiling. Since there is no false ceiling and the roof structure must be visible, the ceiling is designed in such a way that it forms a sound-insulating sandwich. Bags filled with wood shavings are pressed between the metal roof panels on the top and the raffia ceiling on the bottom. It is not perfect, but it helps to dampen the rain falling on the metal roof.

The raffia palm, which is to be used as ceiling material, is usually found throughout the southern part of Ghana and is very often used as a material for building walls, especially in smaller houses. Compared to bamboo, it is not load-bearing, but it is significantly more resistant to insects and requires less protection. It seemed like an interesting alternative to plywood, which is usually used for ceilings. The raffia was delivered to the construction site, but it stood too long in the sun and dried out too much.

Therefore, the original idea of making panels from palm fronds could not be implemented: they became too brittle for a connection. Instead, a much more laborious method had to be applied. Each piece had to be nailed from the bottom to the purlins. The end result was wonderful, aesthetically very successful and improved the frame acoustics, but it was a very long process that extended the construction time.

When the ceiling was finished, the roof opening was visually more emphasized in the foreground. It brings light into the classrooms, but as already mentioned, it lets warm air out and improves the microclimate in the classroom. Next came the wooden window shutters. It was decided to use casement windows, which allow for more flexibility and save space, because they do not extend deep into the classroom when opened. When fully opened, they let in a maximum of light.

And when closed, the shutters are designed to keep out rain. The exterior surfaces of the clay walls and wooden windows were protected by paint and varnish. While the classrooms were being built, the toilets were constructed a bit further away. It was more or less a completely conventional construction method, where everything was built both underground and above ground, from locally made sandcrete blocks. It is actually a nice comparison between two construction methods.

Here it is clear that due to the nature of these cement blocks and their imperfections, an additional plastering is required, which increases cement consumption. But because of the intended function and the limitation of the earth blocks, which are not ideal for moist and wet environments, the use of cement blocks is a logical solution. It is much easier to cut them and lay various pipes. One can be imprecise and make more mistakes, which are common in installation work.

Later, everything will be plastered anyway or clad with ceramic tiles. The toilets in the facility are equipped with water flushing, so a septic tank was necessary. In Ghana, it is common to use biofil septic tanks, which are smaller, as their principle of operation is to separate urine from feces and introduce microorganisms that support the breakdown of biodegradable material in an oxygen-free environment. The finished rooms looked as follows.

There was a lot of light, the classrooms were very spacious due to the greater height and the room was definitely cooler and more comfortable than comparable rooms and classrooms. In addition to the climate advantages, the roof opening brought in more light and became the focal point of the room. The shutters were a nice addition and brought some dynamism to the classrooms. Above all, the view outside was always towards other classrooms and the courtyard. And here are some photos of the finished school complex.

The furniture was the last step and after that the school was ready for the arrival of students and teachers at the start of the 2018-2019 school year. Thus, the construction took six months from start to finish compressed into 20 seconds. This was the first project of this kind that we were involved in. The budget was very limited and we had no experience in Ghana and we did not want anything unexpected to happen and jeopardize the outcome.

The plan was that 1-2 volunteers with an architecture background should be present throughout the entire construction period and monitor the process, clarify all construction-related questions and conduct a kind of quality/budget control. They should act as independent observers, since the partner organization did not have the capacity to secure the overall expenses. We tried to control many aspects ourselves, especially the procurement of materials. In hindsight, this did lead to some savings since the overall costs per square meter were lower than in comparable projects in Ghana, but it definitely took a lot of time and effort.

In collaboration with the construction companies, a very detailed schedule was created, which was more or less adhered to until the end. There were of course delays, but all within a completely normal and logical framework. The volunteers on site communicated with the other project participants in Berlin and during this time frame, hundreds of such screenshots were taken to address various topics to discuss what arose on the construction site. They can be divided into different categories.

The first included our questions about various quality aspects and notes on defects, that were identified on the construction site. The second category was the changes that we proposed during the construction, when it became clear that something could be done better or that some aspects were not considered in the design phase and now needed to be revised. And finally, the most important aspect, the answering of various questions about the construction plans and making decisions on everyday construction topics.

Where does the light bulb go? How should the plywood be cut so that as few leftovers as possible remain? Where is the fuse box? The determination of certain details: Lightning protection? Rainwater drainage? And so on. Things move very quickly on the construction site and one has to react from one day to the next. And it is impossible to foresee every detail and every problem that arises on the construction site. Ultimately, it is always a matter of time and how much of it one can invest in a particular project. Therefore, it is important to set priorities. As you can probably see, in this project we tried to address every possible detail.

This is something we did a bit differently in later projects. So here are some other lessons learned. The materials used were well chosen. The wood was of very high quality, as was the raffia, although a bit too complicated in implementation. The pressed clay blocks were also a nice addition that gave the classrooms an extra quality. The pivot windows are very practical and look aesthetically pleasing, but they have an important weakness, namely the aspect of safety and locking.

In this specific project, safety did not have a high priority, but windows like these can probably be broken into quite easily, since the locks used are not very sturdy. Additionally, opening and closing takes a bit of time, since each window has to be locked with a latch. The roof opening was a great success and we tried to implement similar solutions in most of our later projects to convince our partners to do something similar.

In this specific case, the technical solution was somewhat complex, but it is important to point out that such an opening can also be achieved in a much simpler way. The microclimate in this classroom is clearly much better than in the usual rooms with smaller window openings and false ceilings, which always rely on ceiling fans to make the space livable. As mentioned before, alternative building methods, especially when it comes to the underground parts, must be resistant to water and moisture.

In these cases, there are not many alternatives to cement construction. The ratio between above and below ground parts in terms of the use of cement in this project is probably 1 to 6. We started construction, without having a reliable water source. We are using water from the youth center next door, through a well with a water pump. As soon as the rainy season was over and the dry season began, the well often ran dry.

Since the construction site cannot operate without water, especially in the initial phase with all the cement- and concrete-intensive work, there were many difficulties. The water had to be sourced from elsewhere, which extended the construction time and caused additional costs. Only when the new borehole was completed, there were fewer problems with the water. The lesson here is, first secure a stable water source and only then begin construction. By repeating the same classroom designs, we definitely streamlined the construction.

The construction team became more efficient with each new classroom, the architecture team adjusted some small details and there were many other small advantages. On the other hand, it led to a lot of confusion. The site was sloped and each classroom was oriented differently, so none were really the same. Sometimes it was really hard to tell which buildings we were talking about: the drawings had changed and everything had to be checked multiple times.

In hindsight, it’s fascinating how quickly the surroundings of the school have changed. Only 5 years later, there are so many new buildings there. The public school was also renovated and expanded. And of course, it’s impossible to know what the development of a specific place will look like. Nevertheless, one should try to include potential development in the discussion about the current and future needs of the community, and consider various possibilities, for how the project might develop and change in the near future.

One of the mistakes that were made was certainly that not enough attention was given to the outdoor area and not enough plants and trees were planted. They were indeed planned as a project, but the budget and time were not sufficient. To create an outdoor area that does not become muddy and cannot be washed away in the rain, everything was covered with gravel. It is actually not hard to imagine how a few trees in the middle of the courtyard would have significantly improved the situation.

Here, a definite opportunity was missed, to make the project and the perspective of design and use substantially better. The construction work began with the clearing of the entire site and to begin with the construction, everything must be removed. Especially in Ghana it is usually not a problem, to remove the vegetation, as everything grows back so quickly. What happens here and what can happen in all similar situations, very easily, is that an active construction site with all its normal activities, such as machines, transport vehicles, digging, storing materials, making cement blocks, laying installations, and so on, compacted the ground and essentially destroyed the top layer of the soil.

This and the fact that we built on a sloped site, where rainwater flows down the slope, led to erosion and made the situation even more complicated and difficult to control. This is before the construction, when the vegetation still held everything together and the rainwater was distributed more evenly across the property. This is shortly after the completion of the school. A part of the site has regenerated, but the area around the school building not so much.

Now even more water flowed down and onto the school building. This photo is from the end of the construction work and you can even see the path along which the water flows. The courtyard was covered with gravel, which protected this part, but now the water could no longer flow through this entire area, so that it found its way along the eastern side of the complex. Everything was partially renovated by a newly dug trench that runs across the entire property. It is specially protected with car tires.

It helps to divert water away from the school building and protects the foundations from possible destruction, but even today the fundamental problem persists. The regeneration of the landscape and soil after construction should definitely be taken into account and budgeted, especially in sloped terrain. And the last point, the team. Now this is not a new insight, but it is also something, that one learns again with every project. How successfully a project is implemented, depends primarily on the team of people who carry it out.

The better the team, the higher the chance of a successful project. In this project presentation, we focused primarily on the special features of the building and, in this regard, we all had great luck to work with very reliable and capable construction companies, who organized the construction and the local team very well. Since then, we have seen many other projects and are aware in hindsight of how well everything went. Of course, many adjustments were made by all parties involved. There were compromises, the budget was tight from the beginning and there were some spontaneous, unplanned changes. But overall everything served the project and enabled a more effective implementation.