Flat Roof Coverings Uncovered
In one of our articles last week we gave our readers some advice on choosing a new flat roof. We listed the issues that need to be considered, one of which was the type of materials to be used as a flat roof membrane. Today, we’re going to take a closer look at some of the flat roofing materials available on today’s market, with some information on each so that our readers can make an informed decision on the best type of flat roof for their commercial or domestic premises.
- Torch on Felt – this is probably the cheapest method of covering a flat roof – felt applied hot in two or three layers. However, it’s important to know that there are several different grades and the best felt systems are now comparable with the newer alternatives (and cost just as much). When the felt is built up in layers, it gives a more robust finish which can be suitable for light foot traffic. Applying the felt hot means that it’s easier to apply around corners and penetrations.
- Mastic Asphalt – this is deemed the longest lasting roof covering and is usually used under roof terraces that will be walked on. It’s often laid as a base layer underneath paving slabs.
- Single Ply Membranes – there is a wide range of materials available for this type of flat roof, although PVC (Polyvinyl chloride) is the most common. Other choices include PIB (Polyisobutylene), TPE (Thermoplastic Elastomers) and TPO (Thermoplastic polyolefin), with the latter often chosen by those who wish to avoid the use of PVC for environmental reasons. Single ply membranes are usually fitted by an approved installer and are usually a little more expensive than EPDM but feature longer warranty periods.
- EPDM Rubberised Roofing – this is easily installed and in widespread use due to its flexibility. It comes on cut-to-measure rolls with its own flashing systems. EPDM is usually bonded to the substrate using adhesive and should last for up to thirty years when properly installed.
- Liquid Roofs – complex roof shapes present a whole new challenge for roofing contractors. However, a paint-on solution can be effectively used where other methods of roof covering are not suitable. This is an expensive option on new roofs and usually chosen for an overhaul or repair on a failing roof.
If plant and other machinery are located on the flat roof, then choosing the right roofing solution is vital for both durability and safe access. When regular access is necessary, there will be a requirement to provide safe access int eh shape of a walkway or demarcation barrier, so this will need to be taken into account when choosing a roof covering solution.