Thread: Roofing felt "required"?

Some new homes in this area (east TN), I have inspected lately have had the roofing shingles installed over the wood sheathing without roofer's felt. I understand the Uniform Building Code calls for felt under all first layers of shingles but we have no official code to that effect, in this area. The contractors are saying the felt is only a backup layer of protection, and is not a building requirement.
Comments please.

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underlayment (roofing felt) is required

R905.2.7 Underlayment application. For roof slopes from
two units vertical in 12 units horizontal (17-percent slope), up
to four units vertical in 12 units horizontal (33-percent slope),
underlayment shall be two layers applied in the following
manner. Apply a 19-inch (483 mm) strip of underlayment felt
parallel to and starting at the eaves, fastened sufficiently to
hold in place. Starting at the eave, apply 36-inch-wide (914
mm) sheets of underlayment, overlapping successive sheets
19 inches (483 mm), and fastened sufficiently to hold in
place. Distortions in the underlayment shall not interfere with
the ability of the shingles to seal. For roof slopes of four units
vertical in 12 units horizontal (33-percent slope) or greater,
underlayment shall be one layer applied in the following
manner. Underlayment shall be applied shingle fashion, parallel
to and starting from the eave and lapped 2 inches (51
mm), fastened sufficiently to hold in place. Distortions in the
underlayment shall not interfere with the ability of the shingles
to seal. End laps shall be offset by 6 feet (1829 mm).

Originally Posted by Don Horn

Some new homes in this area (east TN), I have inspected lately have had the roofing shingles installed over the wood sheathing without roofer's felt. I understand the Uniform Building Code calls for felt under all first layers of shingles but we have no official code to that effect, in this area. The contractors are saying the felt is only a backup layer of protection, and is not a building requirement.
Comments please.

If you are in an area that does not have building codes then you can revert to saying that the use of roofing felt is good building practice.

Roofing felt is part of the roof system. It forms the secondary layer of protection for wind driven rain or other leaks. It also protects the shingles from uneven decking and provides a smoother appearance to the roof.

Let the contractors say what they want. Simply report that in areas with code enforcement the felt is required and it is good building practice to use it on a roof. Tell your clients that all roofs should have felt under the shingles. I have not looked, but I bet it is also required by most of the shingle manufacturers.

CASMA - Technical Bulletin No. 3 - The Use of Underlayment With Asphalt Shingles

Don,
Not sure where in East TN you are, but in the Knoxville area it is required. It is in the code, and its also on the bundles of shingles.
Those roofers are idiots.

I'm sure the future HO's underwriter would have an issue with it as well.

Although as I first read your post it seemed you were stating the shingles were directly applied to the roof deck...when I went back and re-read, I realized I ASS-U-ME-d that's what you were saying. If there is for example something other (better) than felt between, such as ice and water sheild, etc. that IS okay, doesn't have to be felt and, but felt OR.

Tell them to follow the instructions on the shingle wrapper, which comes from the manufacturer. They need to do it just like in those little pictures.
Find out the brand and take a picture of the label.

Thank you all. I'm in Morristown, TN. In the city does not appear to be a problem. It is in the county where I see this. I have seen so many lately I was wondering if I had missed a change.

Thanks again

Originally Posted by Don Horn

we have no official code to that effect, in this area.

With no code to refer to, you could refer to a nationally recognized code for guidance, however, the roofer will still say that it is 'not required in that area', but they would be wrong because ...

Originally Posted by Jack Feldmann

its also on the bundles of shingles.

Originally Posted by John Kogel

Tell them to follow the instructions on the shingle wrapper, which comes from the manufacturer. They need to do it just like in those little pictures.
Find out the brand and take a picture of the label.

Even with no code to enforce or refer to as being "the required" way, the shingles are only as good as the installation and the installation is only as good if the shingles are installed as the manufacturer says to do it.

Have the roofer bring in a bundle of the shingles, the correct way is right there on the shingles. Or, once you know the manufacturer and the type/style of shingle, go to the manufacturer's web site and download the installation instructions - if the roofer did not install the shingles as stated and shown in the installation instructions, the roofer did not install the shingles properly (and that includes the underlayment under the shingles).

I've done inspections in Morristown. Like I said before, the roofer is an idiot.

Originally Posted by Don Horn

Some new homes in this area (east TN), I have inspected lately have had the roofing shingles installed over the wood sheathing without roofer's felt. I understand the Uniform Building Code calls for felt under all first layers of shingles but we have no official code to that effect, in this area. The contractors are saying the felt is only a backup layer of protection, and is not a building requirement.
Comments please.

Good catch, Just curious how you found that.

This area has received much more rain than normal this year. (Normal is 50" +/-/year and we are at 75"+/- to-date. I started looking for felt at attic vent opens and roof edges, only because I was running into so many leaks in newer (15 years or less) homes. Have also found missing flashing or flashing installed with no overlap. Roofers in this area concern me. Also, almost no one installs drip edge anymore.

About 20 years ago I inspected a home with one layer of composition shingles and no felt. Of course I wrote it up, suggesting they refer to the manufacturers specifications. Several days later I was in a Real Estate office (this was before email, we had to print and deliver reports) and the listing Realtor on the feltless home asked me to come into his office. The seller was there, and had installed the shingles himself (no surprise there). He had a wrapper from a bundle of shingles, and it did say that 15# felt was 'recommended'. He noted it did not say 'required'. And actually, he was correct. I believe the manufacturer just had very poor writers. I believe they were 'recommending' different applications for different slopes, but it did not say 'required' anywhere on the wrapping.

The listing Realtor asked me to send a letter regarding my error. I faxed a letter to the listing and selling Realtors stating the manufacturer may not require felt, but good building practice does. I wrote that I did not know any roofing contractor that would install composition shingles without felt, and that I had called the first 10 roofers in the yellow pages and all said they would install felt.

No surprise here, either- the listing Realtor proceeded to badmouth me for awhile, telling other Realtors that I was too 'picky' and would not admit when I made a mistake.

If you have a question on stuff like this look on the shingle packages and or call the Mfg. or go on there web. They will advise you on there recommendations. But required by Code.

Originally Posted by Don Horn

Thank you all. I'm in Morristown, TN. In the city does not appear to be a problem. It is in the county where I see this. I have seen so many lately I was wondering if I had missed a change.

Thanks again

Many counties in Tennesse, and other states, have a difference between city and county building codes/requirements. Occasionally it's a vast difference. It's just a situation home inspectors need to be aware of, and find out if it exists where they inspect.

Originally Posted by Daniel Mosier

Many counties in Tennesse, and other states, have a difference between city and county building codes/requirements. Occasionally it's a vast difference. It's just a situation home inspectors need to be aware of, and find out if it exists where they inspect.

That might be true to a certain extent, but the manufacturers requirements and good building practices remain the same no matter where you are.

You will always be correct if you defer to the manufacturers requirements and or good and excepted building practices.

Originally Posted by Don Horn

Some new homes in this area (east TN), I have inspected lately have had the roofing shingles installed over the wood sheathing without roofer's felt. I understand the Uniform Building Code calls for felt under all first layers of shingles but we have no official code to that effect, in this area. The contractors are saying the felt is only a backup layer of protection, and is not a building requirement.
Comments please.

After 16 posts I will chime in

"The contractors are saying the felt is only a backup layer of protection, and is not a building requirement."

It is a shingle manufacturers requirement so it is a building requirement. You just cannot get any more simple than that. It is also a smart thng to do. What if a couple shingles blow off but the rest of the roof is fine. The water goes straight to the sheathing, thru the cracks, thru the insulation and then down thru the drywall ceiling.

Yes it is a building requirement.

Someone used the term "the contractor is an idiot" I would use the term moron as it is a step further.

I my area (Midwest weather) manufacturers recommend or require underlayments, including WSU in some locations, and there are slope-related requirements as well.

I frequently include this and similar documentation in reports as required.

Originally Posted by Scott Patterson

That might be true to a certain extent, but the manufacturers requirements and good building practices remain the same no matter where you are.

You will always be correct if you defer to the manufacturers requirements and or good and excepted building practices.

I agree with you 100% about following recommended installation procedures. I make note of this on my inspection reports when the situation occurs. The only purpose of my post was simply to state that the differences between city and county requirements DO exist.

I have dealt with several roofing manufacturing reps in years past and the bottom line is; if their installation instructions call for felt to be installed then for the warranty to be honored it had better be there.

If it is manufactured required and not installed then the warranty is void.

I have seen roofers only install felt along the along the bottom and gables to fool the reps when there is a problem. But still if they find out it was out properly installed the warranty is void.

Most if not all manufactures will require felt to be installed. Also the pitch will determine which felt either 15# or 30#. 6/12 and below generally will have 15# and above will have 30#.

Again, refer to the manufacture installation instructions. And try to stay out of warranty issues.

Originally Posted by Rolland Pruner

If you have a question on stuff like this look on the shingle packages and or call the Mfg. or go on there web. They will advise you on there recommendations. But required by Code.

Manufacturers play a numbers game, just remember they have a team of lawyers write these instructions. Ask a certified Roof Contractor what and why, you'll get better answers, and answers that you can understand. Manufacturers want to sell shingles...sell, sell, sell. They'll agree and disagree with you in the same sentence, just like a used car salesman. Anyway sorry for ranting on like that but try dealing with them...you'll understand. As far as underlayment is concerned, it is required, on all shingle roofs. On 3-tab shingles and T-Lock (do they still make those?) you could get away with not installing underlayment in so far as they wont leak, but on Laminates it just not going to work with out it.

Regardless of the lack of code, the shingle must be installed according to the manufactures installation instructions. The manufacturer may require a heavier underlayment, or an ice and water shield in some lower sloped applications; see installation instructions.
(edit) Some shingle manufacturers cannot meet some locality wind requirements regardless of the application or the installation instructions so the shingle cannot be used, legally.

The last set of instructions I read (from GAF I believe) had TWO parts:

1. Underlayment is recommended.

and way further down the wrapper

2. Failure to follow manufacturer's recommendations void the warranty.

They did NOT say "required".

BUT, if you want the warranty, the only way to get it was to follow the "recommendations".

Some two faced confusing writing.

Roofing felt came along as a means to keep the home dry until the shingles could be installed back in the early days when mass housing started to be built. The manufactures recommend it as a secondary means but most don't say required because there product if installed correctly will suffice for the life of the material. With that said most standards require it because it has become the norm.
I know in the 80's and 90's it wasn't uncommon for roofers to cut the paper with there knives because of the bubbles in the paper from long exposure or apply shingles after a rain. The felt was then rendered useless.
I have also torn off old roofing materials with no underlayment on homes in the early 1900's with no issues to the decking.

Of course different regions need different approaches because of climates but the birth of felt was due to construction delays of getting shingles installed and wasn't part of the system per-say.

Originally Posted by Mike Schulz

Roofing felt came along as a means to keep the home dry until the shingles could be installed back in the early days when mass housing started to be built.
Of course different regions need different approaches because of climates but the birth of felt was due to construction delays of getting shingles installed and wasn't part of the system per-say.

Mike, where did you learn this?

I've seen a few roofers tear off and/or put a new layer of felt on before they installed the shingles. As you said, if it's been a long time since the paper was put on the decking it's not in great shape all of the time. Most of them probably just snap a few lines (maybe) and start popping the nail gun.

Here is the story I heard in 1965 when I went to work for a builder and was involved in my first shingling experience.
The glue in plywood was corrosive to the asphalt shingle and the shingle would begin to disintegrate from the back because of this. A barrier was needed between the plywood and shingle to prevent the corrosive effect.
We were not using an asphalt sheet. We were using red rosin sheet. This is what the package called for and when I quit roofing 10 or 12 years ago some mfrs. still specified the rosin sheet for the underlayment.


A couple of years later I worked for another builder who was using asphalt felt and I told him this story. He agreed that rosin sheet was specified but asphalt felt was cheaper. He was using the felt as a "sacrificial layer" that would delay the effect of the glue reaching the back of the shingle.

Because of this story- true or not- I always used red rosin sheet under the shingles. (admission: except occasionally when I used nothing).

Felt is perforated at the factory so hot asphalt can penetrate to the layers beneath on built-up-roofs and then you poke thousands of nails through it while installing the shingles. I would not count on it much for leak prevention.

Google and ye shall find!
Try this link, it has the story of roofing felt...

Roofing Felt Information at RoofingFelt.org

Hi John,

I took that from what I have witnessed and from the Certainteed Shingle Applicator manual 4th addition version 2. Here is some of what they say:


Water-Resistant Underlayment was invented to keep the roof decking dry until shingles could be applied. Applying this underlayment is called "drying-in the roof". It was also useful as a separation sheet between the roof sheathing boards and the asphalt shingles before OSB and plywood sheets were used as a roof decking.This separation was important because direct contact with resin pockets in the pine planks caused the asphalt to degrade prematurely.
Intact water-resistant underlayment sheds most of the water that falls on it, but its water resistance is temporary. As the sun degrades, the exposed asphalt the material begins to dry out, absorb more moisture. lose it's strength and eventually tear. The less asphalt used to saturate the underlayment sheet during manufacturing, the shorter its life. Since asphalt is the most expensive component of the shingle underlayment, lower priced materials have less asphalt and a shorter life when exposed to the sun and are also subject to severe wrinkling when wet or even just damp.
water resistant shingle underlayment is not warranted by the manufacture. it is an expendable material because much of its water resistance is destroyed during the installation of the shingles by driving nails through it.

Until recently, only two grades of water resistant underlayment was available: #15 (standard) #30 (heavy-duty). In recent years new categories have appeared known as premium and high performance shingle underlayment. These materials are less likely to wrinkle when dampened.

Cetainteed Shingle Warranty: Q&A

WHY IS SHINGLE UNDELAYMENT REQUIRED? Certainteed does not require that shingle underlayment be used under their shingles for the standard shingle warranty coverage to be in effect on slopes 4/12 or greater. However, when we look at the performance of the roof system as a whole. underlayment has a role to play.
Underlayment is considered to be a important component in the UL fire resistance classification. It can provide back-up protection in case of a shingle blow off, and during installation of the shingles it can keep the unshingled decking dry. For these reasons, and also because many contractors tell us they and their customers believe it is and important part of the roof system, we require its use in the Integrity Shingle Roof System.

(Me) Now this manual is several years old and there thoughts may have been updated since then.

Originally Posted by Leigh Goodman

Here is the story I heard in 1965 when I went to work for a builder and was involved in my first shingling experience.
The glue in plywood was corrosive to the asphalt shingle and the shingle would begin to disintegrate from the back because of this. A barrier was needed between the plywood and shingle to prevent the corrosive effect.
We were not using an asphalt sheet. We were using red rosin sheet. This is what the package called for and when I quit roofing 10 or 12 years ago some mfrs. still specified the rosin sheet for the underlayment.


A couple of years later I worked for another builder who was using asphalt felt and I told him this story. He agreed that rosin sheet was specified but asphalt felt was cheaper. He was using the felt as a "sacrificial layer" that would delay the effect of the glue reaching the back of the shingle.

Because of this story- true or not- I always used red rosin sheet under the shingles. (admission: except occasionally when I used nothing).

Felt is perforated at the factory so hot asphalt can penetrate to the layers beneath on built-up-roofs and then you poke thousands of nails through it while installing the shingles. I would not count on it much for leak prevention.

Countless wind damaged roofs where shingles blew off in storms has saved many a home from tremendous damage inside to wet sheathing, insulation and drywall. I would say that with out felt there would be far more serious damage to homes when a few shingles were lost and the rain was pounding down.

Felt is not on the roof for days or weeks before the shingles as most roofing companies come in and lay the felt and start laying shingles after the roof gets loaded with the shingles.

As far as the nail penetrations all thru the felt? The water rolls right over and down under the rest of the shingles to the eves. Does anything get slightly wet? Sure it does but with out the felt the dollars spent for repair would be many times fold in a vast amount of cases. As cheap as it it. I say use it without hesitation.

I guess the question is: Is felt required?

Answer: If the locality requires it or the manufacturer recommends it to maintain their warranty or comply with material listings- yes.

Report it as you see it- no felt and, if you happen to know the shingle manufacturer, and felt is recommended, state that information.

This is an issue with many products and the contractors installing them. Code is prescriptive and manufacturer's instructions and engineers can trump code.

The issue here is if you have a problem with these products and the installer did not do it to manufacturer's requirements for the installation it most likely voids the warranty.

I see this all the time with products. Then you talk to the installer and they say we have doing it this way all the time, then I ask have you ever read the manufacturer's installation guideline, you can guess the answer.

shingles aren't the issue it's the deck sheathing protection and weather proofing the living space, imo

most around here use OSB i furnish the pdf
more @ APA
they also have good info for wall protection

Ted,

In our area the framers install the felt when the decking is installed. The roofs can sit long periods of time before the shingles go on. As stated it does provide a second layer of protection just like house wrap does for siding.

Originally Posted by Mike Schulz

Ted,

In our area the framers install the felt when the decking is installed. The roofs can sit long periods of time before the shingles go on. As stated it does provide a second layer of protection just like house wrap does for siding.

I do understand Mike. Sometimes the felt has to go on due to time of year weather conditions. That is exactly another point someone talked about, bubbles in the felt and being cut and never corrected with a piece of felt to cover the cut. All this takes next to know time. The felt cost very little. As you say it supplies another layer of protection but I submit that it is the protection. Poorly installed shingles. Wind blown shingles. Poorly installed flashing that if the felt was not in place in most cases the home would be flooded out the first rain.

I was just sent a couple pictures of a brand new 5000 plus sf home that someone did exactly that. The flashing was not in place properly and in that area the felt did not go all the way up. We just had a pretty good rain storm. The water not only flooded a couple rooms on the second floor but made its way to the first floor through the walls and ceilings and saturated the floor with standing water on top on the first floor

The builder tries to quench the inflammation of my clients brain and says" this sort of thing happens all the time" he continued to tell her about specifications on plans and such and something somewhere was not required on the plans so everyone just blew over it and the obvious happened! A brand new home flooded out and drywall ceilings, insulation and wood flooring as well as the roof pulled apart because ...........no one had a brain between the builder, super, framers and roofer and everyone just said. "oh well, stuff happens. It was not called for on the plans so everyone ignored it instead of doing things right. No one took the initiative to even try to do things right which every single one of them have been around for years and should have known better.

Oh well. Now I get a few trips to the home for a tidy some of money and get to call all involved a bunch of idiots. Of course I am a really nice guy and would not do such a thing ...... right!