Felt Paper Under Siding

[Temp97]

Building an addition to the side of my garage and thought I would use felt paper instead of Tyvek. Just happen to have several rolls around. I was told that the felt paper will get hot enough to make the siding buckle????? If the sun isn't shining on it how is the tempature going to rise that much?? Anybody experience this,,

 

[ruren]

As far as I know there is no reason not to use felt under your siding. As you said, it can't absorb any heat that didn't already come through the siding.

 

[KennyG]

Felt paper was used for about a hundred years before the tyvek came out. Unless the area is always heated, I think there's no advantage to tyvek. Absorbing more heat? :laughing::laughing::laughing:

 

[EddieWalker]

Tar or felt or roofing paper has been used in houses for a very long time. It works good, but not in the same league as house wrap. Tyvek is a popular type, but James Hardi has a version that is way better.

The main advantage to house wrap is in it's ability to keep the wind out and act as an air barrier. The secondary advantage is how easy it is to install. Tar paper is a pain to hang. Since you already have it, there's no reason not to use it, but house wrap is just a hundred bucks a roll at the box stores and the James Hardi is twice that amount if you can find it.

Eddie

 

[TRR]

House wrap does not tear nearly as easily as tar paper.

 

[MotorSeven]

Temp, I'm going to jump in here on a mild hijack. So, can you tar paper the interior wall and Tyvek the outside wall? Or do you just let the backing on the rolled insulation take care of the inside?

 

[ROUSTABOUT]

I have sided for years. They recommend that you do not put vinyl siding over felt paper. Do not put it over treated lumber. However, I do both on a regular basis. My next neighbor down the road has siding over felt. I did it many years ago and all is fine. His treated posts on the porches are wrapped in aluminum trim coil. No problems. The felt does absorb heat and retains it longer, it is a petroleum base product, maybe that is why they maybe think it will be a problem. I have projects with siding over felt that have been going almost twenty years now, so I don't see what the problem is with it. Maybe the siding companies like to sell house wrap. To me it is harder to handle a long roll of house wrap on a windy day, plus, I hate the sound of it. Felt is nice, quiet, and smooth.

Motorseven, if you are going to put paper backed insulation and felt, that is a no-no. Never put two vapor barriers together. The paper on the insulation has a tar on it for the fiberglass to stick to, and is considered a vapor barrier. If you are going to use felt or staple visqueen on the inside walls, insulate with paper-less insulation. Two vapor barriers together will accumulate moisture between them and grow mold, you don't want that. Hope this helps.

 

[billybobjimmyjoejack]

What you may have heard was if you install the felt paper on your exterior wall and you do not cover it right away then if the sun shines on it, it will bubble and buckle. Depending on how thick the siding that you put over it you could have some "photographing" of the bubbling of the paper if the siding is thin. The best thing to do is only cover as much of your wall as you will be siding with paper. Don't paper the whole area and leave it exposed to the weather. If you are using Tyvek paper and it is exposed to sunlight for more than six months it voids the warranty.

 

[JB4310]

What kind of siding? I have seen it for ever under wood siding even with aluminum or vinyl over the wood. But there are probably better choices now for directly under vinyl, especially to gain some R value.

I'm sure you could use it though with out any problems.

JB

 

[Train]

Or, someone had tar paper on and installed the siding wrong. Vinyl siding has to have room for expansion and contraction. That means not nailing it tight and leaving enough room on the ends of runs. Remember, vinyl siding has been around longer than house wrap so there are a ton of homes out there with it on.

 

[Temp97]

JB , it's vinyl. I would have said that felt paper is just fine and would have advised it to any one, but as soon as I start a project all the head scratchers come out and ask the age old question "Watcha ya doing that for"!

Thanks all

 

[jinman]

When I built my house with cedar siding, the plans called for felt under the siding and I didn't think to spec Tyvek until it was too late because the felt was already up. On the south facing wall with a large flat exposure and no shade, the sun just beat the heck out of the cedar siding. It dried, bowed, split, and popped out a few nails from all the expansion/contraction. Last year I replaced the siding with Hardiplank over foil faced foam and Tyvek. It turns out that during removal we found the cedar was in much better shape than I thought and very strong despite being dried by the sun and the heat from the tar paper. Even so, with the new siding and insulation, the inside of my house is a different place. What went from a very warm bedroom has now turned into one of the coolest rooms in the house and it's on the third level of my multi-level house. My suggestion to anyone putting on vinyl siding is to consider adding another outer insulation layer under the siding if you live anywhere in the sunbelt states.

 

[Danno1]

My suggestion to anyone putting on vinyl siding is to consider adding another outer insulation layer under the siding if you live anywhere in the sunbelt states.

Or the northern states!


.

 

[JJP]

I can never figure out how with a thousand holes in the tyvek that it all of a sudden becomes an air barrier.!! I always use a 30# felt and have not had any problems. I think there is just too much hype. Plus you can detail windows better with felt and with metal flashing. Thanks.

 

[BeezFun]

A trade journal called the Journal of Light Home Construction published the results of testing that was done at some university about 10 years ago, comparing all the house wraps including felt paper. The felt paper was about as good as the newer house wraps in all categories and really excelled in one I thought was the most important. When felt paper gets saturated it still displays good water barrier characteristics. The house wraps on the other hand passed water easily once they got saturated. Since the primary purpose of the wrap is to be a water barrier, that seemed like a significant point. Also the cost difference is large between felt paper and the house wraps. The other thing I noticed on the job all the time was that the quality of the installation was far more important than what material was used. I saw house wrap lapped the wrong way, no tape on the joints, big sheets torn off by the wind, etc. You could use christmas foil wrapping paper and have a better outcome if the installation was done properly.

 

[wesmann]

That university was probably the Building Materials and Wood Technology department at UMass, Amherst. Lot of great publications for builders and home owners at their site.

UMass Amherst: Building and Construction Technology Publications by Title

check 'em out