Just enough slope to drain water but also flat enough to be a problem if not constructed properly.
Flat roof felt thickness.
As the single ply roofing association spra points out this type of flat roofing is strong durable completely sealed and usually lasts at least 25 30 years.
There are two types of flat roof.
A classic flat roof is either almost completely level or has a very slight pitch of 3 in 12 inches or less.
Cold roofs and warm roofs.
Roofing felt s thickness is actually measured in pounds per square with one square equaling 100 feet of roofing material.
Anderson tecnatorch sbs torch on mineral felt capsheet is used as the final layer of the felt roofing process.
Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot.
We would recommend a different covering such as grp fibre glass.
The product can be used as a waterproofing coating on asphalt fibre cement sheeting concrete and bituminous roofing membranes.
Ikopro solvent free water proofer is an easy to use bitumen based emulsion for roofs.
It s available in rolls that are 8m long and 1m wide with a thickness of 4 2mm mineral or 3 8mm sand.
Insulating a flat roof with recticel powerdeck u recticel s powerdeck u offers 0 024 u value for thicknesses 120mm or more so it s a great thermal insulator as well as a strong and stable board for structural integrity.
Roofing felt s thickness is not a measurement of its depth because it is thin similar to heavy paper.
Of course how many rolls you need will depend on the size of the roof so ensure you measure correctly.
However over the last few decades new and advanced materials have been developed.
Here alternating layers of roofing felt usually fiberglass and hot applied asphalt are combined to create a long lasting roof system.
The most commonly used felts are 15 and 30 with weights of 8 and 20 pounds per 100 square feet respectively.
The flat roof is torch on bitumen with torch on flashing this roof has been patched repaired previously torch on felt roofs have an approximate life span of 10 12 years merely as a covering.
Most flat roofs are typically not as long lasting or durable as sloped ones because the latter shed snow and rain a lot quicker.