Use Tyvek Over Building Felt Under Siding

It s also acceptable to place one layer of grade d building paper or asphalt felt over a layer of tyvek.

Use tyvek over building felt under siding.

Who knows what tyvek typar or the random felt you get at a random supplier tomorrow will do over the next 100 years though. One disadvantage is that they can be damaged by the extractives that leach out of wet cedar and redwood siding a problem shared to a lesser extent with asphalt felt. Felt paper will absorb moisture to some degree and wick it through. Tyvek has its advantages personally i prefer it to typar because it s more durable on site in my experience.

Tyvek will not allow moisture to pass through it unless it is in vapor form essentially requiring it to evaporate before it can be transferred. Felt is preferred by some but i ve seen a lot of felt that has crumbled into dust so i prefer other things. It is also much heavier than house wraps that are made from thin light weight plastic fabrics such as polyethylene tyvek and polypropylene typar. The industry standard for two coat stucco underlayment at least on the west coast is two layers of grade d building paper.

Use tyvek over building felt under siding june 1 2020amirul muncategorized this article discusses the use of roofing felt or 15 pound felt as a building house wrap or vapor barrier and the permeability moisture problems and indoor condensation problems that may occur. Plastic housewrap is not advised for use under stucco because it reacts to the surfactants in cement plaster. Tyvek and r wrap lost about 3 of the cedar extractive mix in 2 hours while felt again lost 30. Housewrap is light easy to work with and has good tear resistance.

The original wrb was tar paper. Felt seemed unaffected by soap still loosing 30 of its water. Tyvek and r wrap lost about 10 of the soapy water column in 2 hours. Another problem with using asphalt saturated felt is that it is difficult to seal the seams unlike with plastic house wraps which can be sealed with specialized tapes that are bombproof.