Exterior, House Building Type, and Concrete Siding Material “Your first impression is that the house is very closed,” says David Barragán of the building he designed with Jose María Sáez in Quito, Ecuador. Stacked concrete forms, developed by Barragán and Sáez and used as planters along the front facade, offer privacy and integrate the building with the site.  Photo 1 of 10 in An Innovative Modular Building System in Ecuador