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TOPIC: Product Selection

Galvalume

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Got some good contractors from your site, but ranges are huge. I got a few quotes on 2400 sq. This is with metal roofing, underlay etc. I got one quote with the recommendation of Galvalume with no color (unpainted?). The gent said that the colored one needs up-keep with their special cleaners to keep the color, so he recommends no color, just ? silver. Would I not want white for better reflection? He states Galvalume has a very high solar reflective rating. Would this be coated? He stated the Galvalume does not need any underlayment, but I was reading that an underlayer was a code requirement. Is it true that it can be put right over the shingles? Thanks, Joe
Joseph Rehm

5/12/2014
He is probably proposing clear-coated galvalume. It does have good reflectivity when it is new though it does diminish some with age. It also has low emissivity. Underlayment is required by code. Many metal roofs can be installed over old shingles and I still interpret the code as requiring underlayment. You always need to check local code requirements. Painted white will also have good reflectivity but higher emissivity. There are many very durable paint finishes available on metal roofs. Todd Miller
Todd Miller
Isaiah Industries, Inc.

5/12/2014
Thanks for the quick response. Is he not required to get permits and a local inspection? or should I check with code enforcement to inquire about the underlayment?. He had advised me that it wasn't needed, but he also had some bubblewrap type underlayment if i wanted at some additional cost, but he said thats just throwing money away as it's not needed. So I guess the galvalume would be OK with or without color. I live in the woods (3 miles dirt road) so color wouldn't make much difference. But as far as reflective qualities and emissivity, plain or white would be best, yes? Thanx
Joseph Rehm

5/12/2014
Does the contractor have to pull any and all permits required? Wouldn't there be an inspection during and after install? or should I inquire about the underlayment from code enforcement? Would the unpainted or white be the best choice for the best efficiency overall. I live in the woods so aesthetics isn't the issue out here. The painted shouldn't change the pricing, would it? and is painted (colored) much of a difference in effectiveness and or emissivity that would make a big difference overall? The contractor had mentioned, when asked, he said he does use some kind of bubble?wrap that he could use, but it would be a waste of money to put it down under the galvalume. thanx not sure if the last one posted.
Joseph Rehm

5/12/2014
Many contractors try to do work "under the radar" without pulling permits, etc. This is not in the homeowner's best interest. Yes, I suggest making sure that the work being done is properly permitted and being done per code. There are some building inspectors who do not not interpret the code as requiring underlayment if the old shingles are left in place. I interpret the code as requiring it, and I think it's a good idea. There are some clear coated galvalumes which have initial solar reflectance in the .65 range which would be similar to white. And I must correct myself from earlier ... some of these products have high emissivity as well. I would ask for certifications on the product that will be used on your home, including its energy star listing, so you can compare it to other products. Todd Miller
Todd Miller
Isaiah Industries, Inc.

5/13/2014
Is a Kynar 500 painted Galvalume roof worth the extra money($3,920) for my roof. I know it has much greater emissivity than the bare unpainted Galvalume. Will that extra expense be offset with much lower power bills? I am putting two inches of Isoboard under the metal. Does the Kynar 500 greatly increase the protection of my roof from rust?
Guest User

10/17/2015
Rich, I have emailed you direct with my thoughts. Todd Miller
Todd Miller
Isaiah Industries, Inc.

10/18/2015
Thank you so much for your prompt response. I haven't received as yet in my email.
Guest User

10/18/2015
That's odd. Let me know if it doesn't show up soon. Todd Miller
Todd Miller
Isaiah Industries, Inc.

10/18/2015
Still no response. My email is [email protected] Thanks
Guest User

10/18/2015
Oops. Sorry. I made a typo in your email address. Will try again. Thanks. Todd Miller
Todd Miller
Isaiah Industries, Inc.

10/18/2015

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