EPDM SINGLE PLY FLAT ROOF SYSTEM
Anyone who is experienced in commercial flat roof repair knows that EPDM single-ply roof systems have been around for more than two decades and holds almost one third of the total market. It has the reputation of being durable and has witnessed considerable research and development over the years to further improve its performance. As a result, the manufacturers are now confident enough to offer warranties as long as thirty years, the longest in the industry.
EPDM has reigned the market for the last four decades with its excellent performance record. No wonder, flat roof contractors, suppliers and the owners of buildings both commercial and residential have preferred it over other counterparts. It is resistant to cyclonic winds, hail and fire. According to a latest study, the roofing assemblies of non-reinforced EPDM is very hail resistant as compared to other substrates like wood fiber, plywood, polyiso and OSB board.
EPDM is climate friendly. It can contract as well as expand with movement. It has been formulated in a way that it can withstand the exposure to severe cold, ozone as well as harmful ultra violet rays making it the most apt material for roof repair. Since there is no plasticizer to give EPDM its elasticity, it does not become brittle. Like all other roofing systems, insulation is equally important so that the building becomes energy efficient. You can of course add additional insulation too which will eliminate the threat of shorting circuits and major issues concerning moisture as well as increasing its R value.
For those in need of flat roof repair or installation, EPDM gives them an array of sustainable options. Both black and white EPDM membranes share same characteristics in performance and are both energy efficient and UV resistant. However, the latter one is the improved version with more energy and ecological benefits. If you are looking to extend the life of the roof, reduce pollution level and increase energy efficiency, white EPDM is the preferred choice over the black one.
Ballasted EPDM Roof System
The ballasted EPDM roof system is a very popular application used commercially worldwide. This system is highly flexible and cost effective which have made it a popular choice among contractors as well as users. Also because it is lightweight and easily installable on any kind of roof, it is a preferred roofing system for many flat roof contractors.
The ballast system is often used over expanded polystyrene insulation, which is lightweight, economical and energy efficient. Because the EPDM adhesives dissolve the polystyrene, the membrane is only laid over the insulation, mechanically attached around the perimeters and held down with ballast. The ballasted system is the most economic EPDM roofing system on the market and it is suitable for various types of buildings. To install, EPDM membranes are first laid loosely over the roof floor. Adjoining sheets of EPDM membrane are spliced together with a minimum of 6″ using splice tape thus forming continuous watertight membrane. This multifunctional system usually utilizes 0.045″ thick EPDM membrane. Once the EPDM membrane is laid, the following materials may be used as ballast:
- Rounded water-worn gravel without sharp edges and with suitable size (20 to 40 mm)
- Concrete slabs (minimum thickness 50 mm) with smooth decorative finish. The installation of protective material between the slabs and the EPDM membrane may be required
- Crushed stone, which must be calibrated; the bigger the stone, the greater the weight. Protective material must be used between the crushed stone and the EPDM membrane
The Benefits of Ballasted EPDM are:
- use of large-scale EPDM panels with fewer splices
- wide range of modern roof decks
- quick installation
- low installation cost
- excellent fireproof properties.
Mechanical Attached EPDM Roof System
When the structure is not strong enough to withstand the extra weight of the ballast or when EPDM has been installed on a surface which already had gravel and tar like roofing materials, mechanical attachment EPDM is the suitable choice. When mechanically attached system is chosen, EPDM is reinforced as they are resistant to punctures and high wind. This system of fastening the roofing materials mechanically is the best option for the structure. Broad panels of membrane are used here which are laid down lightly on the substrate. Panels in the outer parts can be either fastened mechanically or adhered fully while panels inside are fastened with the help of metal pieces like nail plates which are positioned on the panel. There is also a 150 mm pressure-sensitive strips to protect it. The rate of installation for the plates differs according to the rate of wind. The adjacent sheets of membrane are joined together and secured with a tape. There is an overlap with a minimum of 6” so that continuity is maintained and airtight membrane is created. A 1.52mm thick membrane of EPDM can be used for this purpose.
Advantages of installing Mechanically Fastened EPDM are:
- EPDM panels are used on a wide scale
- rate of installation is fast and easy
- light in weight
Fully Adhered EPDM Roof System
This is the most commonly used roofing system, especially for the residential structures. In general, it is less problematic or complicated than the other two EPDM flat roof systems. Fully adhered EPDM application is light weight and has flexible designs. If you need roof repair for irregular or undulating surface, or if the roof is steeped by more than 10%, then this system is the most appropriate one for you. This is also an option for surfaces that cannot withstand the extra weight of ballasts. About 9’ wide waterproofing panels are used which are directly and completely adhered to the substrates using adhesives.
There should be an overlapping of 6” with the adjoining sheets. Pressure sensitive strips are used for the seams between the membrane strips making it airtight. EPDM membrane used for this system may vary between 1.15mm to 1.52mm of thickness. Advantages of using Fully Adhered EPDM are:
• suitable for slopes and irregular contours
• resistant to high wind
• feather weight
• tasteful appearance