Hello everyone! I hope y’all are doing well. I’m almost done with grad school and looking forward to that. Other than that, nothing much has happened. Today, I would like to discuss a recent development in concrete roofing for remote areas.
Scott Hamel, a faculty member of UAA (University of Alaska Anchorage), has developed a concrete roofing tile that can be used in place of cast in place concrete roofs. While working with Habitat for Humanity in Port-au-Prince, Haiti, Hamel noticed that the prefered method of roofing is a cast in place concrete slab because it can double as a second floor if needed and was more resistant to the wind and elements. However, these roofs weren’t adequately designed in regards to seismic issues and this caused a lot of trouble in the Haiti earthquake of 2010. Additionally, the usual method for constructing these roofs is to carry up the concrete manually to fill the form work for the roof which is highly labor intensive. These two combined issues lead him to create an innovative new system for creating concrete roofing. It is concept that was widely used when making clay roofing tiles up until the 1950’s when improved techniques become more common. He created a “thin shell, latex modified concrete barrel roof unit” – curved concrete roofing tile in which latex from old paint is added to create to increase flexibility. To build the concrete shell unit, a mold was designed and the modified concrete is poured in to the mold with mesh metal reinforcement located in the center of the cross section. Testing is being conducted to determine the optimal shape in regards to stresses and construction applications.
There are several benefits to using this type of roofing system. The main one is ease of construction in my opinion. The roof tiles can be made on site on the ground or off site and easily be taken up a ladder to be put together on the roof. Another benefit is the cost; according the article the tile will cost $2 – $3 per a square foot versus $6 – $10 per a square foot for cast in place concrete. The other benefit I find very useful that isn’t mentioned in the article is that it is easily repeatable. Someone with very little experience can build a safe roof and when there is a crisis like a natural disaster a large quantity of these concrete tiles can be built very efficiently on a larger scale as well.
Do you think this would be a good roofing system for a remote area? What if any issues do you foresee? Are there any other applications this could be useful for as well? Thanks for your time and have a good week!
Kathleen, McCoy, “Hometown U: A Smarter, Stronger Roof Design for Haiti and Beyond”, Hometown U, March 1st, 2014, http://goo.gl/xk4k23