I am replacing my roof. What are your thoughts on the barrier products, like Polaralum?
Is it worth the extra money?
I live in TN.
Thanks,
bd
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What type of roof are you buying?
Tamko Heritage 30
No need for fancy underlayments for shingles, you would be wasting your money.
But if it makes you feel good or sleep better at night by all means go with a synthetic underlayment, peace of mind is priceless.
Roofer select 15# felt is best for shingles.
Standard 30# felt is excellent also, but it tends to bubble if it gets wet.
We use #30 along eaves & valleys and #15 over remaining roof areas
[quote=“thebluedog”]I am replacing my roof. What are your thoughts on the barrier products, like Polaralum?
Is it worth the extra money?
I live in TN.
Thanks,
bd[/quote]
I think the other folks didn’t understand what you were asking.
I have used Polaralum on several roofs this year, and one at the end of last year. All the specs and testimonials look really good to me. I’m planning to use it in my attic expansion on my own house (not going to tear off a good roof!)
I’ve also been in contact with the distributor about getting a Mfgr’s Cert. Stmt. so that my customers can comfortably claim their energy tax credit next year. (After I brought it up, they said they were going to submit it for Energy Star testing and approval, and then issue the Cert.) Technically, radiant barriers are no longer referenced in the new legislation, but there is a very good argument for indirect reference.
Since you eliminate the need for felt ($$), and you most likely are going to get the tax credit (30% of material cost, up to $2000 max credit), that brings the net cost down considerably.
I am actually on my way to the shop right now to build my own small test “attics” to compare the attic temps with and without Polaralum, I’d like to be able to tell my customers that I KNOW it works, instead of just that I’m CONVINCED it works.
All that said, whether it is a good idea on your particular roof depends on, well, your particular roof. It also depends on the surroundings, etc. If you’ll post all the detail (types of ceilings, is house shaded by neighboring structures, trees, etc) then we might be able to make a better call on your particular house.
Never heard of it so I did a quick search. Is it really a substitute for undies. The picture on their website had the applicator installing it over felt. Doesn’t look like anything I’d want exposed to weather for any amount of time.
I recall a program I was listening to with an energy “expert” who claimed reflective radiant barriers are not effective. Not to say that’s the truth as I often hear misinformation on roofing. (Sometimes even by professionals)
when i worked in chattanooga in 1996 & 1997 all we used was 15 lb. felt. thats all you need & itll save you some dough.
shingle roofs last just as long with 15lb felt under them as they do with anything else under them.
worry about your shingles and your roofer.
only in the freezing climates do you need special underlayments, and thats because you should not be usin shingles.
gweedo.
Hey, folks, we’re not talking about whether felt is a good enough underlayment for shingles. We’re talking about the pros and cons of a specific radiant barrier underlayment product, serving as both a radiant barrier and as a roofing underlayment. Read up on it before you waste a comment.
[quote=“selfemployedslave”]Never heard of it so I did a quick search. Is it really a substitute for undies. The picture on their website had the applicator installing it over felt. Doesn’t look like anything I’d want exposed to weather for any amount of time.
I recall a program I was listening to with an energy “expert” who claimed reflective radiant barriers are not effective. Not to say that’s the truth as I often hear misinformation on roofing. (Sometimes even by professionals)[/quote]
'Slave,
Yes, the photos show it going down over felt, but the specs say it can be laid instead of felt. Also, Owens Corning issued a letter saying, “…it is acceptable to apply Owens Corning shingles over Heat Barrier POLARALUM ™ Underlayment as alternative [to] asphalt saturated felt. …] Warranty…is valid … when Heat Barrier POLARALUM underlayment is used.” That’s how we lay it, no felt.
There are a lot of experts on all sides, for sure. But it’s like saying “metal’s no good on a roof.” Well, some metal is no good on any roof, and some is good most anywhere, and there’s a lot of room in between. The reason I like this product on the topside is that there is a lot of thermal mass that is saved from interaction with the incoming radiant energy (also note that these energetic photons are vibrating at a wide range of frequencies, not just those corresponding to visible light, which is why white vs. black shingles doesn’t make as much difference as some like to think). Without the barrier, then the decking, the rafters/trusses, the attic air, and even the insulation, are all receiving energy transfer from outside heat sources (in this case, mostly solar). It gets dissipated as heat. Park your car in the hot sun, but then throw a large reflective tarp or “solar blanket” over it. It won’t get nearly as hot.
The specs also say it can withstand prolonged exposure to wet conditions, including snow. The mat is polyester (I believe that’s right), and this stuff is really tough. We put it down with button caps, and it never tears. You almost can’t tear it even when you want to. I didn’t get my “test attics” built today, but I will. I really don’t want to pay the bucks for 2 good accurate thermometers (want to cover the 70-150+ F range), and don’t really want to build them either, but I’ll have to come up with some temp measuring device. It’ll be a good home school project for the kids, in any case.
radiant barrier?
there is no such thing were im at.
sorry.
im still tearin off roofs with no felt
on then.
house didnt blow up or anything.
sorry you guys kill me with all the worryin
about whats under the roof.
i dont roof under the roof.
i put one roof on and dont have to worry
about whats under it.
sorry.
gweedo.
Neville,
Sorry I should have read up on it rather than just look @ pictures. Just reminded me of the foiled paper I often see under siding. Seen an ad for a similar product by Sharkskin in a trade publication.
You said “Park your car in the hot sun, but then throw a large reflective tarp or “solar blanket” over it. It won’t get nearly as hot.”
I agree on top of the car it would be very effective. But lay a sheet of black rubber over the solar blanket and see if it makes a difference. I’m skeptical but have an open mind (in this case)
[quote=“gweedo”]radiant barrier?
there is no such thing were im at.
sorry.
[/quote]
In FL? No RB? That’s a dirty rotten shame, if you ask me (which, of course, you didn’t).
Wait, I think you’re implying that if I didn’t roof under the roof, that I could avoid all those nail stabbing me in the head. I will definitely have to consider this not-roofing-under-the-roof thing.
[quote]
i put one roof on and dont have to worry
about whats under it.
sorry.
gweedo.[/quote]
We all have our different worries. At least we don’t have to worry about the 'gators eating our lunch (or eating our roofers, for that matter).
Any Word on Polaralum. I see a couple of discussion but not one informative answer on the product itself.
I’m am not interested in the opinion of what felt is better for what. Polaralum is a substitute felt from what I read. I know that there are other options but no one seems to be discussing this product. I have to replace my roof soon and can’t find any opinions. Somebody has to have it installed or installed one somewhere.
Opinions are all we have to offer so I guess you are S.O.L.
Neville, I’d be interested in knowing how your test works out. Please let us know.
Thanks
sorry, just read my post and it sounded rude. I don’t mean to say that I’m not looking for opinions, but every post I read never comments on the product itself. This was an opinion about polaralum section. I’m just looking for opinions about polaralum.
How did the experiment go
I have never used that myself,and new to Tn. myself, and have found that the standard products I normally use are not so readily available.Shingle mate,cobra vent,or deck armor.
I sell the complete Gaf/Elk roof system,and It is special order 3 to 5 days for most of the system components,and only 1 supplier in my area can order it.
[quote=“poohhbearr”]sorry, just read my post and it sounded rude. I don’t mean to say that I’m not looking for opinions, but every post I read never comments on the product itself. This was an opinion about polaralum section. I’m just looking for opinions about polaralum.
How did the experiment go[/quote]
Sometimes the captain cannot steer the ship. The waves are pushing to hard. Keep trying, the waves will die down.
Neville, it’s been some time now. Did you ever get your “test attics” built? I’ve used PA once & the customer wasn’t so sure it performed as implied / intended / stated.
As to the OP’s question, yes he is asking about it’s thermal efficacy not about it’s abilities as a replacement for felt in regards to a vapor barrier.
I have a customer up here in the D / FW who wants to install it however I am not sure it is worth the expense.
Anyone else care to comment?