These thick layers of roofing felt are installed by heating the back of the felt with a butane torch and then carefully applying it to the roof.
Flat roof how many layers of felt.
Written by larry bohan on 15 may 2018.
Repeat until roof is covered.
Laying the first nailed layer of underlay felt.
2 step by step guide for felting a flat roof.
You can cover the surface of the felt with gravel for added strength.
This layer is not bonded to the decking so that the decking can move without damaging the felt roof.
There are many different types of flat roofing systems available each one with their own pros and cons.
Lay down felt and secure to roof.
What is torch on roofing felt.
Align this layer with the bottom of the roof.
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.
Some roofing felts are actually glued down.
Add the second layer.
Roofing felt is one of the oldest available options and advances made in the past decade or so have begun to move more towards the torch on approach.
Overlay a second layer of felt 2 to 3 inches and fasten it through the overlay so it secures the top of the felt underneath.
Laying the second bonded layer of underlay felt.
For many years it was acceptable to put even the third layer.
1 materials for felting a flat roof.
These applications are ideal for flat roofs or protective surfaces under roof level decks.
Cover the edges of the roof with strips of felt before laying out the final layer.
Installing any gutter drips.
Asphalt shingles typically can have one more layer added over the top two roofs total.
A third layer of felt needs to be placed.
Apply another layer of adhesive to the top for maximum waterproofing.
This could mean flat roofs may not raise the same red flags they used to.
Add the third layer.
Prepare the second layer.
You will follow the same process as in step 2 for the last layer.
Laying the top bonded layer of top sheet felt.
Steep sloped roof products such as tile slate metal and shakes only allow one layer.
Snap a chalk line the.
It must be installed the full length of all valleys.
On roof slopes of 2 12 to 4 12 the remainder of the roof shall be two layers of 15 felt applied in shingle fashion or 1 layer of ice dam protection.
Prepare the third layer.
Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs.
On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing.
The sequence of laying a felt roof is.
On 4 12 or greater slopes the balance of the roof shall be one layer of 15 felt.
