Morris County Roofers: Article About Fully Adhered Versus Mechanically Attached
Depending on their design, membrane roofs are considered to be either mechanically attached or fully adhered. These terms describe how connected the roof material is the to the roof deck. Each style has various advantages and disadvantages that are important for a building owner to consider when discussing their options with Morris County roofers.
The most common roof type is the mechanically attached roof. About 80 percent of all roofs are mechanically attached, and they are popular because they are faster and less costly to install. They are also easier to inspect because the fastenings are easier to see, and it is easier to determine if they were done correctly. In a mechanically attached roof, the membrane is laid down and screws are driven in at the edge of the membrane. They are then covered over by the edge of the next sheet. The membranes are made watertight by heat welding the edges with a hot air gun.
A fully adhered roof is glued directly to the insulation or roof deck. The process is far more time consuming and expensive. Considerably more fastenings are used to install a fully adhered roof because insulation boards are used. Each board must be independently fastened. There is also the challenge of applying the large amounts of glue required.
The roofing contractors from Peter W Smith Construction of Morris County would be happy to answer any questions you have about roof replacement or roof repair.
If the glue is not applied at the correct time or temperature, the membrane may not adhere fully. Once the glue is applied, a weighted roller is used to press it down firmly and evenly. Some roof types, such as tar and gravel roofs, are also considered fully adhered, although their construction differs slightly from the rolled out membrane type.
Despite the additional cost and time involved, an owner or contractor may prefer a fully adhered roof for a variety of reasons. A fully adhered roof is more resistant to wind uplift or pull and has many more fasteners than a mechanically attached roof. Fully adhered roofs are also considered more resistant to leaks because water may not be able to penetrate the glue layer even if the membrane is punctured. This idea, however, has been discredited by some roofing contractors who believe that the water may dissolve the glue and pool under the membrane, creating an even bigger problem if not discovered promptly.
The decision to install a mechanically attached or fully adhered roof is an important one to discuss with a contractor. Some geographical areas may benefit from a fully adhered roof design.