Takeoffs

Karl Johnson's picture
Posted by Karl Johnson on
Fri, 04/29/2011

Carl Harrigan is our latest Haiti design fellow to visit Headquarters for orientation. He'd already been working in the Haiti office for a couple weeks, getting his feet wet with fellow Construction Manager design fellow Stephane Cherduville. Carl was raised in the United States, but he's Haitian and his father runs a school in the middle of Port-au-Prince.The construction manager team in the Haiti office works with the local construction crews and liaises between the architectural designs and the actual building of the Students Rebuild schools and other projects. As we've discussed previously in the Field Notes, it's no easy task to introduce stringent Western construction practices to a developing nation, and Carl and Stephane are playing key roles making the internationally-funded design work legible to local building companies, all the while strengthening skill sets for these crews to conduct more international work…a special form of currency in Haiti.Carl had a lot to tell me about the bid process–where Architecture for Humanity presents the drawings to contending construction crews who send back the costs at which they would take on the project. Only one crew can win the construction contract, and Architecture for Humanity had a few systems in place to vet the best candidates.A "takeoff" in the architecture world has less to do with rocket science, though some precision is still desired. A project takeoff is an estimation of how much building material is required by a design–Carl and Stephane have been doing takeoffs for the Students Rebuild schools for the past few weeks, as a final step before hiring a construction crew.As part of the bid process, contractors are supposed to put prices to the materials needed for a building and can list what they would charge for the 100 cubic meters of concrete needed for the foundation, as well as their going prices for concrete block, rebar, roof sheeting, truss lumber, etc.Turns out the recent takeoffs were thorough enough that the bidding contractors weren't examining the drawings to verify values. So Carl and Stephane responded by adjusting the bid package–and providing an incomplete takeoff for the bidding contractors to fill in the blanks. This process has yielded more informative bids.Still, performing these estimates is extremely time consuming, and Carl is looking for ways to accelerate the process. While he was at Headquarters Carl was contacting software companies that specialize in this material. There are a few programs that deal exclusively with takeoff estimates by analyzing the CAD files. This seems a bit more reasonable at the moment than turning to BIM programming. BIM, or Building Information Modeling, generates a 3D model of an architects building design, including all the construction elements, and can generate with some ease an estimate of materials needed, and for which stage of construction (thereby determining a schedule for the materials). The program isn't quite fit out for developing countries…what with its pre-drawn double-hung window components and so on. Of course, anyone could start drawing and speccing their own Haiti-appropriate components...but that's a lot to ask at this point.Following Dignité, Pele is the next school entering construction–itself followed quickly by Montrouis and then Home of Knowledge. The bid process and context are evolving with each new project that moves to bid. Eight contractors turned out to bid on Dignité, and each one had previously been introduced to our work. For Pele that number nearly tripled, attracting 21 contractors. With the help of local resources and headhunting sites, more attention is being drawn to our projects by contractors, most of them eager to work within the more demanding specifications of our projects.