Thanks for answering.
I didnt realize the roof was not shingles, but hey that all we got here. I am happy when there is tar paper.
Thanks for answering.
I was watching a show and it was in Canada, where they were re-roofing a home. No tar paper, just shingles! If we ever tried that here, I wonder what would happen!
Here, in Sofla, we are required to have two layers of underlayment. This guy didn’t get the swr (secondary water resistance) credit because the peel and stick wasn’t adhered to the deck…even though he had three layers of underlayment!
The difference for wind mits is “self-adhering”. Tar paper is not used as a water resistance in most cases, it is used to protect the shingles from the wood decking. The wood absorbs the oils and drys the materials out. If the shingles were in direct contact with the wood they would dry and and crack much sooner(ask any manufacture). This is why tar paper is removed in small pieces.
That makes sense now. The entire roof is dependant on the tar paper itself and how well its nailed on. Obviously the membrane has no attaching quality to the decking, and if the tiles are foamed down then the same as well. So cutting strips would be a bad idea.
Was the felt 30 or 42 pound ? I put a granulated torch down on part of my roof down there many years ago. IT was all dependant on how well the underlayment was put on and how well the edges were adheared to the drip edge. The cool thing about that stuff is if you ever get a damaged spot, you just fix it with a soldering torch.
It is code compliant to have the layer of peel and stick over the felt, which was 30Lb. in this case. To get the wind mit credit, you have to cut the peel and stick into 4-inch strips and cover every joint, then take pictures of that while it is going on. I’ll be doing a “roof in progress” inspection next month, and will get pictures, of hopefully, a proper installation.
I don’t believe it is actually “in” the building code per se, but I can tell you first hand as a builder, and also having many re-roofs under my belt in Brevard County, that a thorough building inspector will bust you during a new construction inspection, and require that they be removed and the deck re-secured at those location(s).
Code or not, on new construction it is just good practice to do so, as the biggest concern is that if you missed the truss, the deck is not secured properly at that location, and there is also the possibility of them backing out over time and disturbing the shingles above. On a re-roof it would be damn near impossible to do so, and absurd impo since the deck was nailed off from the original construction anyhow, then re-nailed during a proper “professional” re-roof, and that access via the attic space is very limited.
A lot of AHJ’s in my area are starting to require self adhered membranes (if used) be installed over a mechanically fastened layer of underlayment (roofers agree). This mimics the HVHZ method of SWR. PnS directly on the sheathing is extremely hard to get off and makes repairs and future reroofs difficult. The 1802 has not caught on to this, but I would imagine that this question will be brought up in the next revision of the form. What they should do is eliminate the question altogether and include the discount for SWR on permitted reroofs after 10/01/2007 where the SWR is required, even if it is only single ply felt paper on 4/12 or greater slopes.
When they re-roof, those nails may or may not push up and cause a leak.
My biggest question, and one I have yet to find an answer for, is that when you re-nail a deck, the old nails are there, as a guide and if properly installed, which almost all were, how can you put nails in between the existing nails, and still miss the truss? :roll:
Good question, but you most likely will not be able to ask that question in English. The nail guy is all about speed, not quality. Most reroofs get done the same day (with tear off).
You already know the answer to that one Eric.
The same reason I find 3 nailed shingles here constantly.
30# in two layers is allowed in the building code, in many areas. While the SWR in the wind mit is Self adhering only.
Another example of the 1802 over-writing the strongest code in the country… :mrgreen:
In other news…Eric is going to mow his and his neighbors lawn!
Are you sure it was not re-nailed?
Do you think two layers of 30# is better than a self-adhering, self sealing modified bitumen?
I have had to have nails backed out and re-nailed because the JHA wanted to make sure the area was nailed.
The inspectors that have never built a home do not understand that it is not always the framer not knowing where to nail or how to nail in a straight line.
Some reasons why they may miss sometimes.
Wood is not always straight, even in engineered trusses.
Plywood/OSB not straight,
Trusses bent while installing because of the lifting from the crane, even wind
Walls not straight, plumb or out of square
When possible they should be removed, and for the most part(now) they are. This is near impossible on a re-roof, so get over it.
The biggest issue was framers moving from hammers to nail guns. There was a lack of training and a learning curve. This is one reason why there are wind mits now.
Understanding how we got where we are now goes a long way to understanding the building codes and wind mits. They do heed each other but the do not correlate.
I understand that there is a adhesive type foam that can be applied to the underside of the sheathing…just on the joints between the trusses and on both sides of the top chords, that achieve the secondary means of waterproofing required…true?
Not Icynene, it does not apply here…for sure.
Also I believe that you cannot use 4" strips of Ice and Water Shield on the joints if hot tar is to be used…even if over tar paper…because of the heat…true?
Minor points but just would like to know if I can count on these facts, in your opinion.
For the code you should talk to the AHJ.
For a wind mit you can use the 4" tape or the spray adhesive to achieve the SWR. The AHJ may not allow hot tar with it, especially in your area.
In my area, only one layer of felt is needed on a 4/12 or greater (two ply for low slope). Self adhered is installed only as an option.
I checked Preston. The only thing left on those trusses were the original staples. Roofers don’t usually check for misses when they reroof. And if they did, it would be too late as the dry-in guy is right behind the nail guy.