The best flat roof roofing material is without a doubt a single sheet of rubber custom made for weather-proofing flat roofs, such as for example Firestone’s EPDM product.
That is laid directly onto roof boarding, itself supported by the roof rafters and nagging. Insulating material is normally laid in the space between your two, and if you’re renewing your flat roof anyway you might as well take the chance of renewing that concurrently.
This will almost certainly be the recommendation you receive from any reputable builder or roofer advising you on replacing your existing flat roof.
Until recently the most used material for a fresh flat roof was bituminous felt laid in three layers, the initial layer nailed down and the upper two bonded to the main one beneath with mastic bitumen. Depending on the material used, this could mean heating a good bitumen-based compound to make it liquid, and then pouring it onto the underlying felt and spreading it evenly over the whole section of the roof.
Then you had to hold back for the compound to cool before applying the next layer, and at the end spreading a layer of stone chippings over the roof and bonding it with a chipping compound, this being to reflect natural sunlight and stop the felt and bitumen degrading quickly.
This was altogether a rather messy, complicated and time-consuming job best left to the experts. In addition, there have been several stages where it had been very easy to fail to make the roof weather-proof, e.g. where in fact the edge of the felt met the existing tile or slate roofing of the pitch roof.
On top of that, if, or rather when, there developed a leak in the flat roof, it will be very difficult and messy to discover wherever the rain was getting back in. Seldom would the manifestation of the leak on the ceiling of the room below be directly below the source of it. Water could get through a weakness in the bitumen felt and travel along a rafter before descending to the ceiling board below.
The brand new generation of rubber-based flat roofing systems are far superior. When you have reasonable DIY abilities then you can certainly probably do it yourself, with one other person to assist. You can easily look for a local supplier of rubber flat roof roofing material online, and the current price is only around �6.65 per square metre.
Most suppliers slice the material to the exact shape and size that you require so there are no unnecessary joins, meaning no weaknesses and an extremely long-lasting, leak-proof roof.
The vital portion of the whole process is to make sure that there are no gaps between the rubber roof and any existing pitch roof where rain may penetrate. To ensure there are no problems it is critical to run the rubber material up and under the tiles or slates of the adjoining pitch roof so that any rain dripping from the lower-most row falls onto the rubber, without chance for it over-lapping the edge and getting within the pitch roof.
Also, make sure that the existing slope of the flat roof towards the guttering or other method of water escape is maintained. The rubber is merely glued onto the roof boards and sealed where appropriate with metal brackets or bitumen in such a way that rain penetration is impossible. Mind that roof lifespan covers the entire underneath of the rubber so as to avoid bumps in the surface which could obstruct the drainage of the water away.
Rubber roofs have been proven to last for more than 50 years under all weathers, so that it really is the only real flat roof roofing material that you need to consider when deciding on a new flat roof.