TOPIC: I Have An Existing Metal Roof and Have A Question
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Thanks so much, this helps a lot. We are going to pull down the damp insulation so it can dry out and set up temp and humidity gauges inside and out today so we can see what's actually happening.
I'll forward the pictures to your email.
For a vapor barrier, do we need to add something above the insulation in the non-vaulted parts, i.e., where there's an air gap?
Where the insulation is in the vaulted parts there is no air gap and there doesn't appear to be a moisture problem.
One more question. Since we are having condensation problems in the summer should we install A/C units to help dry the air? I would imagine this will only get worse next winter.
I can't thank you enough for taking the time and sharing your knowledge. You're really bailing us out here.
What are the overnight temperature though and what direction does the roof face? You can have condensation on the outside of of your windshield in the middle of summer in the AM and I suspect that is when the condensation is accumulating in this case (i.e. early AM or overnight lows).
Low was 70 last night. There is condensation at 10 today but it's not as bad as yesterday noon. Yet.
The long sides of the trailer are the east and west sides. Right now only the west side (where the sun hasn't hit yet) is showing droplets on the inside of the metal roof panels. The east side is dry. As dry as anything is at 77% humidity.
You are correct.
I just pulled some insulation down and it is in fact, condensation. Now how do we go about fixing this the right and way?
Should we take down the insulation where the gap is and install it so the insulation is adjacent to the roof? Like it is on the peaked roof part (no condensation where the insulation meets the roof directly)? Should we do this and install attic fans? Or just attic fans? Or just re-do insulation?
Would you please recommend the next, best course of action for us to fix this problem?
Over night temps are in the low to mid 70's - usually 73-74 degrees, consistently through autumn. Highs are in the high 80's to low 90's, consistently, too. I live in the Jacksonville, Florida, area, so the humidity is 100% in the am, and 50-70% at various times throughout the day. The long side of my trailer runs east and west and is not shaded.
Thanks Eric for your prompt replys and great advice. I can't thank you enough.
Pull back the insulation, condition and dehumidify the space, treat any mold growth, install insulation (Spray foam works well here if you like), insulate, install air barrier.
I've pulled back the insulation in the problem areas and I have fans pointed at them to dry them out. There's no AC available at this time so the next step is bringing in a pair of 70 pint dehumidifiers (for 980 sq. ft.). Once we get stuff all dried out we'll tack the insulation back up, with some plastic sheeting on top of it. If it stays dry we'll have the drywall installed and make sure it is sealed to the shell at top and bottom and where the interior walls come in contact with the outside walls.
Thanks so much to both Eric and Todd for the prompt and helpful advice. Can't recommend you guys highly enough.
I have an existing pole building with metal sides and roof. No insulation. In the mornings I have condensation on the bottom side of roof panels. It sometimes drips like rain. The shed is 26x48. I put plastic down and poured concrete on an 18x26 area on one end, the rest of the floor I put down plastic with 2 in. of gravel on top. It helped alot, but I still have the condensation problem. What is the most inexpensive way to resolve this?
Most inexpensive is likely a product like this: http://dripstop.net
It sounds good, but it seems like it would be very difficult to install on an existing roof. Is there any kind of a paint type product that could be sprayed on. A local lumberyard told me of an old product called Insulgaurd that might work. Any thoughts on that?
I do not know what Insulguard refers to. Sorry. You could spray the underside of the roof with closed cell urethane foam.
Thank you; How thick would I have to spray the foam? What retailers can I find it at?
Sorry, generally, this would not be a DIY product. Something of this will require special equipment and chemicals, not just "spray foam in a can" unfortunately. You'd need to go to an insulation contractor with the right equipment and they will have recommendations.
Okay; Thanks for all the advice.
I have one more thought on this to run by you. What do you think about installing aluminum bubble foil between the purlins. Tight to the steal. Just thinking out of the box.
I do not think that will resolve the issue.
We just built a 12×42 porch onto our house. We put a metal roof on it with sheating and vapor bearer. We woke up to dots of water laying where all of the screws were put in. How do we fix this problem?
How about some pictures?
Did you receive the pics?
Sheila, for some reason the photos did not post. You can email to me direct if you wish. [email protected]
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