Flat roof EPDM installation quality, wrinkling/buckling at seams?
Is the membrane really supposed to look like this? See below. I intend to have the builder cover this roof with rocks, it is in view from the large windows in upstairs bedrooms, it also faces south so there is a disgusting hot rubber smell with the casement windows open. It would have been great as a green roof, but the architect decided this was best.
I think I’ve heard it’s actually more the siding connected to this roof that is at higher risk of water damage but I don’t see how this thing is not going to leak… I’m just thinking of the super expensive custom kitchen below this roof and I don’t have confidence this is going to hold up very well. Just curious if this looks normal because I have not seen many/any roofs like this from above. The wrinkling is worse now than it was initially ~ 5 months ago (photo below from late winter).
Is there anything to be done to improve this? I am not sure if I should have my builder do anything to fix this or if it is fine and we can just cover it with the rock garden/pea gravel.
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How old is the roof?
While I would not worry about the wrinkles in the field, it is not top quality workmanship
I would not expect it to be the source of leaks
The edge needs to be repaired.
I am not sure what is going on there, I would expect to see one piece of edge tape right at the edge of the roof over the drip edge
The roof was done ~ 5 months ago. I notice that the wrinkles are more pronounced now than they were initially, see photo attached of how it initially looked. The seam on the left is that same seam shown in my current photo, so you can see the difference in the wrinkling. I will note that it was very wet (late winter) so it had been covered with a tarp prior to installation, but I would not be surprised if it was not perfectly dry under the membrane at the time of installation.
We’re paying like a quarter of a million $ for a GC, it it unreasonable to expect them to redo this or repair in some way? I don’t understand how the project manager saw this work and approved/accepted it.
YOu need to bring in a different roofer and get an assessment of what is going on. I don't know what the drip edge is, and seaming is not what I am used to seeing
Interesting, I will tell my GC.
Izzza,
I agree with gusfhb. It doesn't look good, and Im not sure what is going on. The lapping seems odd at the perimeter and whatever those small strips are they should be fully adhered.
Good workmanship would not have wrinkles. It can be hard or impossible to avoid bubbles directly after installation, because of the adhesive off-gassing, but they should eventually settle down, not get worse. At least that's the case with fully adhered EPDM. I wonder if your installer only sealed the edges? I have heard that can be done if the field is covered with ballast (such as stone) but I've never done it that way myself or specified it on projects I have designed. In any case, it probably won't affect function.
The fishmouth at the perimeter is a much larger concern to my eye. There are a few different ways of handling the perimeter, and there is a chance that this in only a piece installed for insurance. But in most cases it's an important part of the waterproofing system and should be fully adhered.
Either way, this is not up to a minimum standard of workmanship, so yes, your contractor needs to deal with it.
Thanks Malcolm, Michael! It’s hard for me to know when something like this has been done incorrectly or poorly because I have no experience. I constantly point out details like this and it seems nobody else is concerned so it makes me think I’m just overreacting, the professionals can handle everything without my oversight… but I find so many problems, it is hard to trust anyone 🙃
The front entry porch also has a ‘flat’ roof but it looks a bit different, I am not sure if it is better but at least it is not over the kitchen! Additionally, this one is not sloped away from the house but rather to the side gutter. And when it rains we have dripping against the siding in that area, you can see a bit of pooling nearby on the upper right corner.
Large sheets are ungainly, especially if you're working alone or inexperienced, especially if both the underlayment and membrane are both coated with contact cement and there is no room for error. The first one I did alone, a large deck three stories up via a ladder, with integral gutters and curbs, bubbled after installation. I was so upset about it that I tore the whole thing off in a rage and had to start over. Then I learned that bubbles are normal.
YOu should have seen the first one I dealt with. It would make you feel better
The second one is on my current house, and it has some wrinkles similar to those pictured here, because it is a low pitch, it was a large sheet[~56x20] and was sliding down the roof. I don't worry about leaks from those, and after we split the sheet the rest of the roof was fine
My brother and I did a sealed deck for our father and it came out flawless
third times the charm....
needless to say I am an ambitious amateur, a pro should not have these issues
Love the screws left on the deck
It is possible again that there is something going on outside of my experience, but I would have edge tape over the flashing at the near edge of the roof in this pic.
I noticed evidence of previous ponding in your previous pics
On a truly flat roof EPDM does not mind a bit of ponding, as long as it is not over a seam or significant enough to stress the roof.
EPDM is used as pond liner, so it doesn't care about water
I’m glad I didn’t try to DIY the roofing then, sounds tricky. This one seems relatively easy as it’s only like 11 ft off the ground. The main flat roof over kitchen will take a big snow load from the large gable roof above. I think it’s questionable when it starts melting and we have all these weird seams everywhere.
I found a good video and he shows the same thing - #1 sign the installer knows what they are doing is lack of wrinkles. Hmmm. https://youtu.be/PIqrEEkKtLY?si=0qdcJfSZ4r-dEbNF
Haha I’m glad someone else noticed the screws left behind… I nearly sent that to my GC but I think I can just brush them off with a broom and spare the trouble.