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Why You Should Consider Torch-On Felt

Tuesday, 15th May 2018

 torch on roofing felt being applied

What is Torch-on Roofing Felt

Torch-on roofing, or torch-down roofing as it is also known, is a flat roof covering solution that involves three layers of modified bitumen (felt) melt-welded onto the roof surface and each other with the use of a blowtorch to create an impenetrable, waterproof seal.

Traditionally, the three layers used in this process are a vapour control sheet, reinforced felt and a cap sheet with mineral finish. Using three layers of felt is required by building regulations for habitable areas of a home. For sheds and garages, only two layers may be needed.

The dangers of applying these layers with the use of a hot flame makes torch-on felt roofing a job best left to the professionals. 

Torch-on roofing felt is known as one of the quickest and most reliable flat roof installations readily available in the UK and has become a popular system for these reasons.

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What are the Benefits?

rooflights on a torch-on felt roof

As touched on above, a torched-on felt roof is a quick and straightforward job for roofers who know what they are doing. One of the factors that adds to this quick installation time is the ability of torch-on felt to be applied in both dry and wet conditions. This is one advantage it holds over other popular flat roof repair solutions such as GRP and is an extremely practical plus point when you bear in mind how suddenly the British weather can turn.

Torch-on roofing felt’s reliability lay in its resistance to UV rays, strong winds and rain. The mineral finish of the felt breaks up sunlight as it hits it to stop the bitumen from melting. This means temperatures inside applications are kept cool during the summer.

In terms of disadvantages, the hazardous nature of working with flames means most people will likely have to pay a labourer to carry out the job. When selecting what roofing company to go for, remember to get multiple roofing quotes to help minimize your costs.

Torch-on Roofing Felt Prices

rolls of torch-on roofing felt from Bailey

This, of course, all depends on the surface area of your flat roof and whether you require new decking or any other kinds of repairs.

To hire a roofer or roofing firm for a three-layer torch-on felt job on a single garage, expect to pay between the £750-£850 mark, a figure lower than other popular flat roof systems such as GRP and fibreglass.

Though torch-on felt roofing is not the cheapest option available, the long-term value it offers makes it a smart, cost effective solution that requires little maintenance.

Torch-on felt roofing can last anywhere between 15 and 25 years, depending on whether it’s a 2 or 3-layer system. Many of the layers you need for a torch-down roofing system can be purchased at Roofinglines for the best prices online guaranteed.

What Applications can Torch-on Felt be Used on?

finished torch-on roofing felt application

Torch-on felt can be applied to concrete, timber and metal deck flat roofs, and can form the covering for garages, sheds and flat roof extensions. As well as residential applications, torched-on roofing felt can also be applied to larger, commercial buildings.

Under no circumstances should a torch be applied direct to a timber roof deck or timber upstands, including timber fillets, even if the substrate has been treated with a bituminous primer.

If you are repairing an existing flat roof, it is possible to torch the felt over the material already in place provided those materials are in good shape. If your current roof is not in good nick, it makes most sense to remove any old material and start over.

At Roofinglines, our felt cap sheets come in a variety of colours to allow you to decide on the final look of your roof. Choose from black mineral, green mineral and sanded cap sheets from Bailey.       

What Other Accessories do I Need?

torch on roofing felt grun torch

All reputable roofing firms and roofers should provide all the tools needed to create a professional looking, long lasting torch-on felt roof, along with the correct safety gear. This includes blowtorch, utility knife and protective goggles. All can be purchased at Roofinglines, including grun torches.

You will of course need to provide the extra materials needed to complete the look of your flat roof, whether you are self-building or not. To ensure your new flat roof is a professional, aesthetically pleasing and even more water resistant one, edge trims should be fitted around the roof's perimeter to direct water towards the gutter edge.

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