Do I Need Felt Paper Under Siding

Decades ago the original form of house wrap used was asphalt coated felt paper.

Do i need felt paper under siding. Felt paper also commonly referred to as tar paper is an underlayment material applied to bare walls before siding is installed. Asphalt felt tar paper the standard requirement is type 1 felt meeting astm d 226 standards. The paper requirement is typically omitted for other types of siding when they re installed over rated structural sheathing. This underlayment is an important line of defense against moisture penetration.

They were built in the 1950s and 60s the felt was in perfect condition. I need to do some repairs under my siding from a window leak. I have seen literally hundreds of houses stripped of asbestos siding that had 15 felt under it. A paul fisette director of building materials and.

It is an age old choice as a weather barrier under roofing and siding. For example an ice dam or roof leak may allow liquid water to get behind the felt or housewrap. Yes the main purpose of asphalt felt on walls is to act as a wrb. Alone among the codes boca in its 1998 supplement requires a layer of 15 felt over the sheathing regardless of the siding type.

But because the vinyl siding covers the felt paper it is shielded from the sun and never gets hotter than the temperature of the siding from solar gain. Asphalt felt is required by almost all model codes to be installed between the siding and the sheathing. On walls it has been eclipsed in new construction by various brands of house wrap a woven or spun bonded plastic. Over the years house wrap materials have advanced providing far more protection.

Should any water get past the siding properly installed felt paper. In fact many builders disagree on the effectiveness of house wraps altogether and while some builders will only install 15 pound asphalt saturated felt paper underneath exterior siding others swear by plastic fabric house wraps such as typar or tyvek. Tar paper also known as building felt is tar impregnated paper. Our house was built about seven years ago.

Before delving into why you should have house wrap under your vinyl it is essential to understand what exactly house wrap is. The short answer is that felt paper is fine as a weather resistant barrier behind vinyl siding and will not cause a problem if the siding is installed correctly. That has always been the reasoning for requiring asphalt felt. Install flashings metal self adhesive or both as recommended by the window or door manufacturer or as required by local codes.

Install pieces in the correct order and make cuts carefully so any moisture can travel downward at all points without slipping under the wrap.