Single ply flat roofs are now replacing the popular asphalt roofs since they are an economical and durable alternative. However, the major disadvantage with these roofs is they do not have any natural drainage facility. They are suitable for climates where there isn’t much rain and snow. The flat roofs constructed in recent times are guaranteed to last at least 15 to 20 years unlike their predecessors.
Different types of materials can be used for construction of flat roofs. They are built-up roofing (BUR), modified bitumen, single ply, and sprayed polyurethane foam (SPF).
1.Rules to Follow
Roof installations require you to obtain a building permit from your local zoning office. There are specific rules and regulations that apply to single ply flat roofs and you will have to adhere to these guidelines when having your roof installed.
Different types of materials can be used for construction of flat roofs. They are built-up roofing (BUR), modified bitumen, single ply, and sprayed polyurethane foam (SPF). SPF is the newest of the methods or products to be implemented into this industry. Single ply is preferred in flat roofs because they are lightweight and have a combined layer of membrane and weathering surface. The membrane used is ethylene propylene diene monomer (EPDM).
2.Single Ply Roofs
Single ply roofs mostly use EPDM as the membrane and this is available in 10-foot wide rolls which can help limit the seams and makes it easy for the installer to trim it with a knife. Other materials used in single ply roofs are polyvinyl chloridem (PVC) and thermoplastic polyolefin (TPO). PVC roofs are considered more durable while TPO roofs are more economical, and both need a special machine to join their seams. Modified bitumen, especially the type which can be just peeled and stuck on is also used in single ply roofs.
Hot air welding is one of the techniques used in installation of single ply roofs. The roofing panels will have some kind of adhesive backing and this joins together when it is exposed to hot air. Chemical adhesives are also used to hold together the single ply roofing sheets. Roofing panels installed in either of these ways will also have an additional layer of material such as fiberglass installed underneath the roof to provide it with additional and terrific strength.
3.Spray Foam Roofing
The main advantage of spray foam roofing is that it provides some insulation. After the foam is applied, a layer of acrylic or urethane comes over it. The last layer is of sand or fine stone and this keep’s the sun’s rays at bay. If the foam layer is damaged at any time, it can be repaired with a bit of caulking. Also known as SPF, this is composed of isocyanate and resin and though it can be applied on all kinds of roofs, is more often seen in flat ones or those with shallow slopes.
Before applying the foam, the roof must be prepared in the right manner. If this is not done correctly it can lead to the foam not adhering properly to the surface of the roof. Cleaning the roof will help remove items such as leaves, gravel, and dirt. You may also have to eliminate any existing roofing material before the foam can be applied. During the preparation process, you can replace any vent caps or flashing on the edges of the roof that might have been damaged.
The common method of applying the foam is to use a machine to pump it out of the large drums used to transport it to the site. The machine used is one that heats up the chemicals in the right proportions and applies it to the roof surface. The process of application is done in stages and will continue until the required foam thickness is achieved. After the foam sets, a protective coat of silicon and acrylic is applied to protect it from ultraviolet (UV) rays. Another method of UV protection is to embed granular material in the upper layers.
4.Doing what needs to be Done
Whichever type of material is used and whatever the technique be, by making an effort to sufficiently seal and weatherize each piece of the roofing material, you will be ensuring its maximum performance and long life.