Insulating A Roof Without Felt

The roof can usually be insulated under the rafters with sheet insulation and incorporate a vapour barrier.

Insulating a roof without felt.

If the roof is nailsick the slates should be removed with a proper slate ripper and checked for cracks and kept for reuse. He also found a water stain on the living room ceiling and recommended that the. Depending on your climate you ll need r 30 to r 49 to meet code which is 5 to 8 1 2 inches of polyiso rigid foam which is r 6 per inch. I would lean toward adding rigid foam either on top of the roof or on the inside under the joists if reducing headroom isn t a problem.

Roofing felt may be necessary for use with your shingles to meet a class a fire rating when shingles are evaluated for their fire ratings it is done on a small test deck with the roofing felt underlayment in place without this underlayment the shingles alone may not meet the class a fire requirements. Traditionally we ve insulated the roof panel to try and keep the temperature on the panel from reaching the dew point. Roofing felt was introduced primarily to act as a secondary barrier against wind driven snow and rain but its use also causes a reduction in air movement within the roof space particularly if the roofing felt is impervious and this effect is often compounded by the introduction of insulation. Add a preinstalled membrane to absorb and release the condensation as it forms with the natural weather cycle.