Find a Professional

Double Bubble under Metal Roof?

Back to Galvalume
Back to Archive
Back to Forum
Guest User
12/19/2006
We are in process of getting quotes on a metal roof install on a tri level home. Several contractors have recommended a Metal Master Millennium Premium Coated Series with Ultra-cool coating from BASF. Energy Star compliant. (I hope I can say the brand name, but that roofing system seems to be popular here). Install will be a 29 Gauge Galvalume Metal Vertical Panel over existing shingles. Due to heat issues in the upper levels of the house several contractors have suggested “Double Bubble” insulation (foil on one side) under the metal roof over the existing shingles. Ventilation in the attic seems adequate but heat transference from the roof into the attic seems higher than normal as there is currently a 20+ year old dark shingle roof currently in place. I feel that the metal roof will make a difference by itself, but I was wondering about the Double Bubble Insulation under the new metal roof. The additional material will add only about $600 to the install but wasn’t sure of any pros and cons of doing this like: Moisture retention, any real heating/cooling savings by adding the insulation, early degradation of the metal roof because of it, etc… Any advice or background info you can provide is appreciated. [email protected]
Allan Reid
Dura-Loc Roofing Systems, Inc.
12/22/2006
It must be installed 1" away from the metal roofing to be effecive. The energy star roof will go a long way. Tests at the DOE though have shown that a vented air space under the metal is the most effective way of reducing heat transfer in the summer. That means selecting a system that goes on strapping set off the deck. The higher the air space the better the ventilation. This is required by code for any vaulted ceiling areas.
Guest User
12/24/2006
A system that goes on strapping set off the deck is some good advice for us to think about. Do you know of a place online where I can read up on the Roofing/building code? Thanks
Allan Reid
Dura-Loc Roofing Systems, Inc.
12/27/2006
I have not found one as yet and end up buying one on line. It is a good investment as it will allow you to do it once and do it right.
Guest User
11/13/2008
i was told 1 by 4 purlins are enough but thats not 1 inch clearence. is that not the standard of the industry?
Todd Miller
Isaiah Industries, Inc.
11/18/2008
There are several different issues here. Please give me a call at 1-800-543-8938 ext 201
Find a Professional

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Professionals in your area for a free consultation and estimate.

Search Now