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TOPIC: Installation Process

Proper decking underneath metal roof

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A contractor recently put a metal roof on our new 750 Sq ft addition. The joist are 16" on center. He screwed 1x4 to the joist, a foil bubble wrap type insulation to the 1x4 and then metal directly to this. This is a heated and cooled living area. The ceilings are 8ft and cathedral but do have a an air space created by the truss with r-30 insulation and drywall seperating the attic space and living area. Does this sound ok to you? I am afraid of moisture problems. It also seems like a structural strength issue also. A couple different contactor i spoke with say this not the way a metal roof should be put on a house. I have seen sheds and barns built like this but not a house. So I am concered. Any ideas or opinions would be greatly appreciated. Thanks
Guest User

12/15/2009
You would need to contact the metal roofing manufacturer to find out whether their product should be installed this way. However, this may work. I would have liked to have seen a vapor barrier (polyethylene) behind the drywall or ventilation beneath the roof. Todd Miller
Todd Miller
Isaiah Industries, Inc.

12/25/2009
I called ABC metals they said they prefer wood under the metal when applied for residential application but that it would probably be ok if ventilated properly. I noticed the ridge cap is sealed off completely with the bubble wrap insulation. I am also concerned with the corners he put on not extending past the drip edge. He also seems to have got the metal on crooked. Can you tell me if it is standard to apply metal without the wood decking underneath on new residential metal? I am thinking of installing an attic fan to help with airflow. Do you think this would be a good idea or necessary?
Guest User

1/4/2010
Another photo
Guest User

1/4/2010
Another question I had is the installer missed the 1X4 strips in quite a few locations. Will the screws give me problems later since they are not attached to anything but the metal.
Guest User

1/4/2010
For a residential installation, I too would have preferred to see decking and underlayment but what has been done is not uncommon. I would encourage you to contact ABC again and send these photos to them. Most of the issues I see are cosmetic but I would like to have the manufacturer weigh in on things. As far as the missed fasteners ... that is unusual. It should not have happened very often. The fasteners will probably be okay but, again, I would suggest checking with ABC. Todd Miller
Todd Miller
Isaiah Industries, Inc.

1/5/2010
Thanks I will check with them on that. Do you think an attic fan would be a good idea to help with ventilation? The ridge cap is sealed up completely with bubble wrap.
Guest User

1/5/2010
I would shoot the contractor. That is a totally unacceptable job.
Mike Clark

3/15/2010
That is the worst looking piece of crap installation I have ever seen. Does the contractor exclusively hire retarded monkeys? He should, they would do a better job. Sue the bastard and get a real contractor in there to replace this monstrosity!
Guest User

6/5/2010
You poor man, what an insult this craftmanship is. Truely an insult towards trusting an installer. Don't let this guy ruin your hopes of finding a good contractor. We do good work most especialy now with jobs few and far between. God bless you Sir
Guest User

8/15/2010
I see many issues in the installation of this roof. The first being that the "addition" is way out of square or the exposed fastener panel is "out of module", either of which creates an aesthetics issue. I can visibly see a variance of 6" between bottom and top. The second is the improper placement of the fasteners to achieve proper adherence to avoid wind uplift problems. The installer didn't fasten the panel properly at the eaves or ridge. The panel’s manufacturer has a tested fastener pattern available on the web site. Just look for it. Thirdly, the installer did not use closures at the eave or rakes and you are going to have severe insect and other critter issues, no to mention water, ice & snow infiltration. He also didn't use proper eave trim at the eave & facia. No butyl sealants were used where trims overlap and where they were employed, they were haphazardly applied. Lastly, you are going to have condensation issues in the near future. I see absolutely ZERO ventilation in the attic area. My conclusion, you got taken by a fly-by-night contractor who has zero knowledge of installing metal roofing. I can foresee a lawyer being involved in this in the near future. The cheapest bidder is not always the best option.
Guest User

8/15/2010