Week 6

Our model home is officially done! We finished constructing the roof early last week and added a curtain to the door and louvres to the window on Friday. We have two thermometers that we will check periodically throughout the day to keep track of the temperature and humidity so that we will be able to compare our results to altered future versions of our structure.

We have left a few of the bricks unmortared and the roof is easily removable so that we can apply and test any new components we design into the existing structure without difficulty. Our group has kind of naturally split into groups so that some of us can work on the roof elements and others can work on alterations to the blocks and their configuration.

After some of the team had taken their vacation week, we all reconvened in New York City on Wednesday for a whirlwind day of taking in culture, exploring, and learning. We started the day at the new SUNY Downstate campus medical building, where we took a tour of the building under construction. It was really interesting to see what goes on behind the caution tape at a construction site and to get a close look at all the internal steps in the building process. 
After our tour, we visited the Ennead architecture firm office. They are the firm working on the SUNY building, so we were able to talk a little more about that building as well as other ongoing projects they’re working on. While it was cool to see the SUNY building, our main reason for visiting the office was to talk with one of the partners who had worked on a project building a school and community space in rural Zambia. She gave us a really nice presentation on the project and a lot of good insight on all the things that go into making a project like that possible. About halfway through our own project, this provided exactly the inspiration we needed to keep us motivated and excited. 
Next we headed to Little Senegal where we had a delicious, authentic meal and explored some of the local shops. It was nice to reminisce about our time in Senegal and to experience a little taste of the culture for our team members who were not on the trip. It was a great day packed with lots of fun and interesting activities. Today is our first day with the entire team here and we are feeling inspired and ready to keep working!

Week 5

We’ve made tremendous progress this past week. Thanks to Abby, we finally found a way to get our blocks to release smoothly from the mold by lining them with a thin layer of plexiglass. While this works really well, we decided to break down and buy premade concrete blocks so that we’d have more time to work on the more important stuff. However, we made a new custom mold with the plexiglass lining to make the smaller uniquely sized blocks we need for around the door and the window.

Our premade concrete blocks arrived last Monday, and already we are laying the final course of our structure. All of our smaller custom blocks have been cast and should be dry enough to use tomorrow. With the walls almost complete, all we really need to do is decide on how we want to attach our roof before we can start taking observations and measurements to compare to future models. 

At this point, we hope that each person will be able to develop their own idea that they can take the lead on in implementing into our existing structure or future structures, whether this be a new variation on the standard block or some other innovative component to incorporate into the walls, roof, window, or door. This is where all our early research will really help. We are having our weekly faculty dinner tonight to discuss our progress and where we would like to go next.

Week 4

With two new block molds ready to go, we started the week with high hopes. Because we’re constructing a fairly small building, we’ve decided to build two new molds at 75% the size of the original. We figured this would allow us to produce more blocks in less time, and at a more manageable size. After making some initial alterations to the new molds on Monday, we started laying our new blocks on Tuesday. Unfortunately we’ve since had a few setbacks since. While we’ve gotten pretty good at mixing the concrete, filling the molds, and flipping them, we’ve been having a lot of trouble with the release. The corners and insides of the blocks are not coming out cleanly.

After altering our mix ratios and varying how much we packed the molds and having little success, we decided to look into ways to facilitate the release of the concrete mix from the wood mold. The bad news is we still haven’t found the perfect solution. The good news is it has forced us to be pretty creative. So far we’ve tried spraying the mold with cooking spray, lining it with recycled plastic bags, brushing it with vegetable oil, and lining it with heavy duty aluminum foil. We may try vaseline, but based on the results using other oils, we are not too hopeful for this approach either. We would like to have a metal mold like they use in Senegal, but unfortunately these are not for sale and would take too much valuable time to make for just the control building. We are having a planning meeting tonight with our advisers to develop our next strategy.

On a more positive note, all of our group members are now woodshop and 3D printer certified as of this week. We have also had some downtime to start drawing and making small scale models for future projects to begin once the control building is built, like a miniature sandbag mock-up out of sand, balloons, and glue. Although we don’t have a ton to show from our work this week, we’ve definitely learned a lot and remain optimistic.

Check out Lehigh’s website for an article by Kelly Hochbein about our project! http://www1.lehigh.edu/news/better-buildings-senegal

Week 3

There was plenty to do this week! With all of our materials here and plenty of sun, we were able to start the heavy lifting. We spent the beginning of the week mixing concrete with different cement to sand to water ratios and then tested all of these ratios in smaller molds, so not to waste too much material. While ideally we would like to use as little cement and water as possible to make it most realistic for the Senegalese, we kept finding that the concrete blocks with lower ratios were not holding up well enough. Ultimately, we decided that we will use the same cement to sand ratio as they would in Senegal (about one to three), but we will be using slightly more water since the sand we are using is a little different. Since we are not specifically looking to change the materials of the blocks right now, we decided it is okay to alter the block composition to fit our needs even though it is not entirely accurate. We are still getting an authentic Senegalese experience by mixing all the materials by hand and laying the blocks in the hot mountaintop sun!
Once we had a rough idea of what ratios worked best, we started mixing larger quantities to fill our actual block mold. It took some trial and error trying to determine the best ways to pack and flip our blocks, but we now have some pretty good samples! After all of our experimentation, we are now looking into how we can alter our mold to make the process run more smoothly. We’re on the right track! We will continue making blocks and hopefully be able to start constructing something next week.

Week 2

We have received permission to start building and have marked off our designated site! We received a few bags of cement, lime and sand today as well as other necessary building supplies.  As soon as the rest of the materials arrive early next week, we will begin making blocks and constructing our model home. In the meantime, we have been researching possible directions we would like to explore once our control model is built. To maximize productivity, we split into two groups to look at different components.

One group has done comprehensive research on ventilation, looking into several ways they can modify the existing techniques to allow for more airflow. This is a vital and often lacking component to homes in Senegal, but poses a lot of potential issues. The goal is to create air circulation while preventing heat, bugs, and sand from entering the homes with the fresh air. Our first idea is to create all of the walls out of CMU, with a bottom row made of brise soleil blocks. We want to incorporate a type of screen mechanism in the brise soleil openings to prevent the entry of mosquitoes. The top of the building will have a row completely open brise soleil. There will be a barrier below that row which acts as a ventilation barrier and bug screen between the living space and the top of the house.  The top brise soleil blocks will be where most of the sunlight enters the house for visibility.

The big question of the week was Why do homes in Senegal not have screens when disease carrying mosquitoes are such a big issue? We came up with a few reasons, such as screens make the homes appear unwelcoming, they can easily damage in weather, or they are simply not cheap for people in Senegal to buy. We tried to experiment with different ways we could hide a mesh screen into a brise soleil block so it is not visible. Next week we want to explore different textiles people could use instead of metal to make it cheaper and easier to obtain for senegalese people. The 3D printing sustainable development group wants to work with us in the future and we are hoping to find a way we could 3D print screens with plastic made from recycled plastic bags.

We also experimented with different ventilation systems such as thermal chimneys and wind scoops. Thermal chimneys have a metal material on the top which attracts heat.  Below there is a corridor that allows air to rise and then funnel out of the building, circulating cooler air up through the house. The same concept can be applied to the south facing fall of a building. Heat is attracted to the metal wall and then a corridor helps funnel hot air up and out of the building. The corrugated metal roof is beneficial to these types of systems, instead of heating up the building to extreme temperatures like they are currently doing in Senegal.  Wind scoops can be used in multiple sides of the dwelling to help direct incoming winds through the space.

The other group continued researching earthbag construction and brainstormed how we could expand upon existing techniques being used in similar areas. A square or rectangular home constructed out of sandbags would look very similar to the existing concrete homes in Senegal once they had been covered in cement. The problem is that a rectangular structure typically needs wood frames distributed among the sandbags. Since wood is not widely available in Senegal, dome shaped structures would probably be a more viable solution. While these may provide different aesthetics, they also open up other opportunities for building.  

Since the dome shape tapers up to the top, one idea we had was to build a screen or some kind of low emissivity barrier into the sand bag layers towards the top and then leave the very top open. This way air would enter through the door and windows then the hot air would rise to the top and exit the building through the top. The screen would prevent bugs from coming in and then some kind of slightly elevated, removable or permanent cap could go on top to prevent rain and direct sunlight from entering. We could also easily incorporate a rain collecting device by adding a slanted ledge near the bottom of the dome that would collect the rain and siphon it into one area to be collected.

Another idea we looked into was incorporating sandbag homes into the traditional Senegalese compound and courtyard. One way this could be done is by creating one large, torus shaped building that housed a courtyard in the middle. Some things to consider are the fact that this type of building would probably require a separate roof and the shape of the building would not really allow for additional buildings to be added on to the compound as they typically are in Senegal. We also considered building lots of small domes and bridging them together as they get added on. This would allow for small corridors that could be treated as communal space and would also allow for an outdoor courtyard to develop naturally as it does with the current building techniques.

Ideally we would like to be able to construct two additional smaller scale models to test some of these ideas once our initial building is complete. Then we can compare them to see what is the most efficient building.

Week 1

The Summer team is off to a great start! Now that we have moved into our Mountaintop space in Launch Bay C, we have begun researching, brainstorming, and creating. Our preliminary work has included setup, planning, shop training, and familiarizing ourselves with our workspace and resources. With these initial steps out of the way, we can move on to our next phase.

After reviewing the raw data collected by the travel team, we determined that the main issues we want to explore are heat, ventilation, and sunlight in the homes. We will be keeping in mind cost, climate, and aesthetic value as we explore solutions to these issues. We may also explore finding a way to incorporate plastic into our design to help reduce the abundance of improperly disposed plastic waste found in Senegal.

Our first step will be constructing a 2m x 2m room made of concrete blocks with a corrugated steel roof, one window, and one door. This models a typical Senegalese living space and will be used as a control for comparing any new techniques we experiment with this summer. We have an initial list of materials we will need and some of our team members are already started constructing our block mold in the wood shop, so as soon as we get permission and have everything we need, we will begin constructing our Senegalese model.

We have also begun brainstorming and looking into possible techniques we might want to try or expand upon after we have completed our first model. We have considered rethinking the standard cmu block to incorporate a brise-soleil component in it. The advantages of this approach would be that it provides ventilation and airflow while obstructing direct sunlight. The cons would be that it allows for bugs and dust to enter the space, so we would have to figure out some kind of screen system to prevent this. 

Another technique we have researched is the use of earth bags for construction. This seems like a viable solution because sand is abundant in Senegal, so material cost would be very low. Sand also serves as a good insulator, so this could potentially keep the spaces cooler. These are still in the very early stages of the project, but we excited to start building and to see where our preliminary ideas take us!

Building Descriptions and Floor plans

Building Descriptions and Floor Plans for the Main Four Buildings We Observed While in Senegal

By: Ansah Kamara, Pat Wendler, Chris Guilcapi, and Ellie Hayden

Fallou’s Home

During our time in Senegal, we were able to observe a large variety of typical Senegalese homes, ranging from urban to rural areas as well as different socioeconomic backgrounds. One of the first homes we spent time in was a single family home in an upper-middle class neighborhood of Dakar. This was home to Fallou, a language professor and former advisor to the Senegalese president, and his family. They lived on the first floor of this multi-story home and rented out the other levels. Fallou mentioned that this style of building stems from the mentality that men will take multiple wives and the multiple stories will allow for separate living spaces within the home similar to a compound. He presented this idea as sort of a joke, but there is some truth to it.

Fallou and most of his family have spent a lot of time living in the States as well, so much like his family, this home was kind of a hybrid between the two cultures with many traditional Senegalese aspects and American influences as well. Unlike many of the other homes we visited, Fallou’s house felt very secluded and private from its surroundings. It also had a formal indoor kitchen with many appliances which was uncommon from what we observed in the other homes. Although it was a single family home, the way it was set up had a similar feel to many of the compounds we visited. There was a wide hallway that ran down the middle of the house with several rooms branching off of it. This hallway had a couch, several chairs, and a television and served as a common space for socializing like a courtyard would in a typical compound. Even though there was a formal living room, we spent our time in the hallway.

Aside from two small open-air courtyards built into the home, it was fairly closed off from the outdoors. For this reason, the house was cool and comfortable both times we were there. The larger courtyard accessed the bathroom and shower and also served as a space for outdoor cooking, prep, and laundry. The smaller courtyard’s purpose was not as clear, but it seemed as though it would be used for serving and eating meals. It was interesting to see how these outdoor spaces had been incorporated into an urban home. It allowed for some air flow in the home and a little bit of natural light. However Fallou’s main complaint was that it was always dark. This poses an interesting paradigm for Senegal, as natural light is so abundant, but is often blocked out to avoid the heat. Overall, this seemed like an efficient use of space. The only issues we determined were the lack of natural light and that the smaller courtyard was not being used to its potential.

Aminata’s Compound

A great contrast to Fallou’s house was Aminata’s family compound in Thiaroye, Dakar. Aminata is the sole bread-winner of her family, selling jewelry on Goree Island and thus earns a relatively low income for her large family. This low income is a reason for her residence in Thiaroye, which is one of the lowest-income areas of Dakar. Because of Thiaroye’s low income and closer proximity to the city, living spaces there are small and densely populated, making it hard to tell where each compound’s respective space was. One observation we made specifically of Aminata’s compound was that it was small and densely packed like the other compounds. Because of this, the living space had minimal area but maximal use, and open space was thusly scarce. Another observation we made was that there was poor airflow in the compound due to the density of buildings and lack of open space. The compound, though small, was the main area of daily activity. It was where cooking and work was done and animals were kept. Aminata’s room was partitioned by a curtain into two areas: a back room with a large bed where five of her family members slept and a front room with a broken refrigerator, a large dresser, and a mattress on the ground where three of her family members slept. There were no windows in the room and the door was kept closed at night to keep mosquitoes and dust out. This caused airflow to be largely absent within the room, save for an electric fan. The roof of the room was made out of fiberboard, which is cheaper than metal and has a lower thermal conductivity, but is less durable and leaks during the rainy season.   

Sleeping House

The house we stayed in in Keur Momar Sarr was a newly built, single story home that was not being lived in yet. It was gated off towards the outskirts of the town. The majority of the homes were in compounds similar to Meissa’s family, but we did visit a couple other single family homes similar to this one. The home had a large shed with an adjoining bathroom and shower that was outside of the main structure. This home also possessed a kind Senegalese/western hybrid-type feel like Fallou’s house, but in a lower-income, rural environment. Like the other single family homes we saw, the individual rooms stemmed off a large main corridor that we suspect will be used as a communal courtyard type space. In the front of the home the hallway was semi-open to the outdoors with a very large window with just security bars. This allowed for airflow in the hallway, but not so much in the individual rooms. Each room had one window opposite of the door, so there was a bit of a cross breeze when both were open, but this was an issue at night due to the bugs. Since the house was made of concrete it stayed relatively cool during the day, but released a lot of heat in the late afternoon and into the night. We recorded a high of 88 degrees Fahrenheit in the evening. There were three bedrooms, one adjoining bathroom with “Toubab” appliances, and what appeared to be a formal living room probably intended for guests. It was unclear as to where the cooking would be done. There was a staircase that led to the roof which had a half wall enclosing is so that it could serve as a deck for hanging laundry, but also allows the home to be easily built up in the future. The main problem we determined for this building was the heat and lack of airflow late in the day and into the night.

Meissa’s Compound

The other space we spent a lot of time in Keur Momar Sarr was Meissa’s family’s compound. This compound had a large, sandy courtyard which served as a multipurpose communal space where people congregated to socialize, do laundry, play (the children), prep food, etc. This courtyard was much more spacious than the one we observed in Aminata’s suburban compound. This makes sense seeing that it is a much less densely populated area in a rural environment where space is plentiful. Surrounding the courtyard were several individual concrete rooms built off one another, an outdoor pit latrine and bucket shower, and a fenced off area for the livestock. There was also a small semi-open kitchen/cooking space tucked back behind Meissa and another’s room.

We spent the majority of our time in Meissa’s concrete room which was a small rectangular room with one window, one door, and a small covered patio area just outside. The window and the door were on the same wall, so there was very little cross breeze. During the hottest part of the day, from about noon until three or four p.m., it was more comfortable to be inside than outside. However due to the nature of concrete, heat was released into the space later in the day, making it more comfortable to be outside in the evening and night. The metal door was kept open during the day with a curtain separating the inside space from the patio, but the door was shut at night to prevent bugs from entering. We had one or two fans going most of the time we were in this space. We observed a high of around 87-93 degrees fahrenheit late in the afternoon. Meissa’s roof was composed of corrugated steel with a lower specific heat than concrete, thus explaining why higher temperatures were recorded in this building compared to the house we slept in in Keur Momar Sarr. The slant of the roof had been constructed keeping in mind the possibility of future buildings rather than considering the direction of the sun. He had hung a tapestry between the roof and the living space, partially to act as a buffer and partially for aesthetic purposes. The covered patio outside acted as sort of a buffer to the heat since it provided a little shade for the air before entering the internal space. We determined that the biggest issue for this space was the lack of ventilation and natural airflow in the individual room.