Tuesday 28 February 2017

Rymans Store Camberley Mall

Tradecall Roofing Camberley 01276 501755

www.localroofers.uk

Todays Felt Roofs Last

This type of flat roof still has a bad reputation with some people, but I’m going to tell you why that perception is out of date. Most people have in mind the old ‘pour and roll’ felts of yesteryear, and these were thin bitumen felts glued together with a hot liquid bitumen between each layer. They had minimum internal reinforcing, with some containing natural hessian fibres which were prone to rotting. This type of felt, sometimes known as rag fibre ,would effectively dry out and crack with age or UV damage from the sun. 10 years was pretty much the life expectancy.

Modern torch on felt roof

Torch on felt roofing, in case you hadn’t guessed describes the method of application. Do not confuse these modern roofing felts with the older pour and roll system. Great strides continue to be made in bitumen and modified bitumen technology such as SBS or APP, resulting in much better resistance to UV damage and cracking.  This type of felt roof comes on rolls and is laid with the aid of a very large blow torch that heats and melts the rear of the felt, melting it onto the roof structure below. Typically it’s applied as a 3 layer system usually consisting of a perforated underlay, a 2mmor 4mm underlay layer, then thick 4-5mm felt. These layers are all laid in a half lap manner, so all the joints are the furthest away they can be from another joint.
The thickest top layer is often a coloured mineral finish known as a cap sheet, and they are available in a variety of colours, as well as a plain felt finished with a silver solar reflective UV finish. All of these felt layers are also reinforced with strong polyester weave sandwiched in the middle of the felt, giving them incredible strength. In lifespan terms, I don’t know a single roofer that will not be happy to guarantee 10 years, because they know it will last 20, sometimes 30+.  Not as bad as you thought is it?
 
 
 
 

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