flat roof house

A Guide to Installing Flat Roofs with PVC Roofing

Flat roof installations are simple to pull off. The roofing used can either be gravel, tar, PVC, rubber or modified bitumen. Each material will require different techniques for application. PVC flat roofing, also called vinyl roofing, resembles rubber roofing in concept. However, it features seams that are welded with heat to make them long lasting.

As a result, your PVC roofing sheets have to be handled with care; otherwise, they will produce leaking problems. Heat welding is also dangerous, and so it needs skilled personnel. When installing vinyl flat roofs, the following are the three techniques used.

Fully adhered method

In this method, you need to set the deck with the laying material before welding the seams. You also need to attach a flashing. A fully adhered technique means that installation will join the flat roof material with the deck using an adhesive. This method is to be used only for roofs whose decks are impermeable, for example, a concrete roof. The process also demands that the roof’s perimeter is installed with a mechanical installation.

To install a flat roof using this method, you need to work at temperatures exceeding 40 degrees Fahrenheit (4.44 degree Celsius). At lower temperatures, the glue will freeze. Consequently, the roof deck and the PVC will not stick. Full adhering comes with one problem. As the PVC bonds to the deck entirely, it is possible for condensation to form below the roof. This is especially the case if the roof’s ventilation is inadequate. Condensation, over time, will cause the roofing to loosen and it can blow off if there are strong winds.

Mechanical installation

With this method, installers will use metal plates and screws to join the PVC with the deck. It is an excellent option for people who live in high wind areas, as it is almost hurricane proof. Typically, every membrane row of the deck will be fixed with screws, usually placed 12 inches (30.48 cm) apart. These roofs are fast to install and cost relatively less than fully adhered roofs because they do not require special conditions to install.

Builders who opt for this method go for it because a manufacturer can inspect the job and validate the installation by looking at the patterns in the fasteners. Ideally, two membranes on top of each other should create a watertight seal. Any gaps are then sealed with hot air so that the roof is single, flat and waterproof.

Ballasted installation

modern flat roof house

This method of flat roofing makes use of ballast, which is a material that weighs down the roofing material so that it stays in position. Here, the installers will lay the PVC material loosely on the deck. Instead of screws or glue, they will use a layer of rock to keep the material from moving.

PVC roofing has become popular because it provides certain advantages. The material provides moisture resistance, strength, durability, and resistance to chemicals and fire. However, enjoying these benefits is a function of the installation done. Be sure to work with licensed professionals to enjoy the most benefits of this type of roofing.