Timbrel vaults offer another low cost, sustainable roof building method. This method is suitable for do-it-yourself owner builders if you do the research. Suggestions include: use a simple design with a reinforced concrete bond beam and modest spans. Look into using low-fired, lightweight brick like the type used in Mexico and SE Asia.
“The ‘Sustainable Urban Dwelling Unit’ (SUDU) in Ethiopia demonstrates that it is possible to construct multi-story buildings using only soil and stone. By combining timbrel vaults and compressed earth blocks, there is no need for steel, reinforced concrete or even wood to support floors, ceilings and roofs. The SUDU could be a game-changer for African cities, where population grows fast and building materials are scarce.”
Source: No Tech Magazine (This site has hundreds of great articles on low cost living and building!)
11 thoughts on “The Sustainable Urban Dwelling Unit: Timbrel Vaults”
I have tried the timbrel vault method before on our house, and although our experiment turned out to be a failure, we did learn a lot.
Tiles in our area were very hard to find, and expensive (we are in Northern Mexico). This was the most difficult obstacle to overcome.
In his book, Guastavino recommends using plaster of paris for mortar of the first layer, which we did, but as you add layers above this, moisture soaks into the plaster, weakening it, and can cause failure without formwork. So, take special care when using gypsum-based mortars.
There is a big learning curve (no pun intended) with these vaults. Make sure you do several small roofs/ceilings before attempting something larger.
Insulation can be an obstacle with these. Where do you put it? If you want insulation in your roof, you are better using these as ceilings or possibly the outer roof layer. I am not sure how well they work as a waterproofing layer.
If you are using them for porches or other outdoor areas that don’t require insulation (buried house?), then they should work fine.
Great input, thanks for sharing.
Here is a blog that documents how the SUDU house was built in Ethiopia. It is a two story structure, and uses timbrel vaults to form both the floor of the second story and the roof.
Amazing. Let’s hope the contractors there don’t discover 2x4s and sheetrock.
Thanks for the “showpeice” treat! Excuse my ignorance, but you mentioned reinforced concrete bondbeam. Is the bondbeam the part “arching” and runs along the edge of the vault, or is it on top of the supporting walls upon which the vault sits?
Bond beams are designed to contain outward thrust. They’re typically horizontal and on top of the wall. But the example in the photo is unusual. In this case I would call the curved portion a beam.
The Timbrel Vaults are so beautiful … structures that viscerally inspire, what could be better. Thanks
They’re not very common since concrete became popular. Occasionally an architect will use the technique on showpiece architecture like this: http://www.archhis.com/bldg/?bI=15942
These structures are absolutely beautiful! The region of Queretaro, Mexico, is famous for its bovederos. There are some great videos on youtube of them.
Do you have any research information about the use of this type of structure in areas where earthquakes are a risk? e.g. You can use them, you just have to use “X” amount of reinforcements
You need to use twice as much rebar in the bond beam or something like that
you can only span a limited space.
I have spent quite a bit of time googling and have not had much luck. I emailed a guy who wrote a book about the Guastavinos but he didn’t know where to send me. I live in southern Mexico around 19.3 -98.2.
I’ve watched some of those and agree they are great. I even considered adding one along with the blog post.
Timbrel vault roofs are not practical for seismic areas. Consider something like ferrocement. It’s lightweight, has excellent tensile strength and meets code. See today’s blog post. All the technical building details are free on the Internet.
Steve’s site is great! He has gone to great lengths to put his work on the web. I’ve been in contact with him and even asked him about going out to his place and watch how he works his magic and he was open to the idea.