Commercial Flat Roof Construction

Commercial roof construction often utilizes a flat roofing system over a flat roof. Flat roofing is just that—a process where several roofing components are layered to construct an excellent barrier from outside elements. In Texas, protection must be particularly forgiving of high winds, especially along the coast, and extreme summer temperatures throughout the state.

Roof Inspection and Make-Ready

In existing construction, the first task lies in the removal of the old roofing materials and their safe disposal. Next, an assessment is made of the under layer and structure. The existing substrate is checked for soundness. Is wood rot evident? Are worn surfaces apparent, or are holes in need of repair? After all necessary repairs are complete, the roof installation begins.

Flat Roofing Construction Process

First, a rigid insulating material is fastened to the substrate. Generally, roofing insulation consists of an impregnated cardboard and wood fibers,a fesco type material made from volcanic ash and vegtable fibers,A foam type material known as Polyisocyanurate (ISO), or fiberglass based products all which have different levels of fire retardant capabilities and R-values. With hot summer temperatures, determining the appropriate insulating material is essential and is based upon the building's contstruction. Metal buildings, for example, are veritable ovens in our summertime temperatures and require quality materials.

Next, a base layer is fastened mechanically or adhered to the insulation, which is generally a asphalt saturated fiberglass membrane product. There are different types of roofing products available for flat roofs. One of the oldest methods is a hot asphalt roof which requires an asphalt kettle to heat asphalt which is mopped over the roof, however; Torch applied and Self-adhered membranes have become more popular through the years. The application of hot asphalt, helps to both apply a waterproof barrier and for adhesion to the substrate and or insulation.

On hot asphalt roof applications an interply membrane is sometimes used for added protection. This layer is usally mopped in hot asphalt as well. The final step is called the cap-sheet which is sometimes a modified bitumen material with a wide range of specifications for use in this type of application.