DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Roofing and Siding (
-   -   Question about leaking side trim of flat roof (

dayton 08-30-2009 09:46 PM

Question about leaking side trim of flat roof
Hello, everyone.
I was on here a few months ago and got some brilliant advice for exposed beams that were starting to deteriorate. So I'm back with another question, unfortunately.

When I first purchased my house and would tell people that it has a flat roof, I would get looks of sympathy and didn't really understand at the time. Inspection showed it was good to go for another 7 years but upon doing some work, I've found quite a bit of flaws that were covered up cosmetically by the previous owner of the house.

My latest issue is with the trim that runs along the side of the home. There are random seams (maybe about 10 in total) that all started to leak to various degrees. Instead of sending the water back toward the gutter, it allows water to leak down the seams, which is going to cause some corrosion of the wood in the underside of the overhangs.

I'm not sure how big of an issue it is....whether it's time for a whole new roof or if I can seal these up somehow to keep the seams from leaking.
I assume that they are aluminum but they may be galvanized metal.

Is there a sealant product I can use to keep these from leaking? I haven't looked up above at the roof (I can fairly easily, I just haven't checked it out). I was hoping some kind of DAP sealant would work if I seal it up nice and proper and have several dry days for it to cure. But again, I don't know much about roofs (I am learning more with research) but I wanted to see if anyone had experience with something like this for some potential advice.
Here's a photo of one of the can see how the water will come down the seam and get to the wood underneath.

I've no problem with stopping the damage to the underside but I know that's futile unless I can stop the problem first and foremost.

Again, any suggestions or advice are greatly appreciated. Thanks in advance.

ps: the debris stuck to the side is just wet leaves that have blown and stuck to it as we just had a pretty bad storm 2 days ago.

EDIT: One more question...I have 2 leaks in the gutter as well that had been welded together.
Is another weld the only proper fix or is there some high powered sealant I could use on that as well? Those must be galvanized steel...the previous owner told me only that they had been welded and that they were custom built and very expensive.

oldognewtrick 08-31-2009 05:44 PM

Dayton, I doubt the the lap seams are the reason you are leaking, it is most probably leaking from the top. If you could show a picture of the top of the roof it would help a lot to identify the source of the leak.

Flat roofs are a good installation option when they are installed correctly and are a pain when the materials are misapplied.

Your gutters were most probably soldered and not welded. Trying to get the joint clean enough to re-solder at this point would be useless, its very difficult at best to solder metals that have been exposed to the elements. A solution would be to get a "gutter caulk" thats made for wet applications.

Hope this helps and please provide a picture if you can of the roof membrane.

dayton 08-31-2009 07:17 PM

I will definitely get up there and get a shot of it tomorrow. I appreciate your suggestions for the gutter. When I'm up there tomorrow, I'm going to take some steel wool and clean the gutter seam up really well and get some gutter caulk on there and see if that remedies the gutter issue.

dayton 09-01-2009 01:40 PM

Here are some photos from the top angle. It's a pea pebble flat roof with asphalt that is spread out to the edges. There is a lip there that I assume is to route all of the water to the back gutter.

The only place where water drips is where the seams meet. Several places around the exterior show the evidence of the water coming directly down the seams as there are about 10 of them or so around the perimeter of the roof.

I'm guessing a good weatherproof/waterproof sealant successfully loaded into the top lip seam and then carried on down the vertical seam down the side might do it?

There is no evidence of leaking on the interior or anywhere else, thankfully.

top seam:

oldognewtrick 09-01-2009 06:52 PM

Dayton, I was really hoping to see something different on your roof. Get a good rubber based caulk and try caulking the seams as far as you can get on top of the roof, then down the sides. Try to get one the color of your gravel guard or clear so it doesn't show so bad. Then start saving your lunch money for a new roof, sometime in the future you will be seeking the services of a roofing contractor. Do not use silicone because it does not have enough elasticity.

Good Luck

dayton 09-01-2009 08:19 PM

Thanks again for the input. It's about time for a new roof so I've been expecting it...just putting it off as long as possible and trying to maintain in the meantime.
What should be up there? Is the asphalt wearing back too far away from the edge of the trim?
I'm just curious as to what you were hoping to see that might have made a difference.

Like I said, I did a thorough inspection on all interior/exterior parts of the roof and there's no sign of leaking anywhere except the seams.

I have looked into a rubber roof for a replacement but that likely won't happen until next summer.

oldognewtrick 09-03-2009 07:06 AM

Rubber roofing is a great product IF installed correctly and maintained throughout its lifespan. The problem is installers who don't use all the accessories and try to take short cuts. Remember none of the major MFG warrant their products on residential applications.

Gaf "Liberty", Certainteed "Flintlastic", ABC "Mule Hide" have available self-adhering base sheet, cap sheets that are really good products for flat roof applications and carry residential warranties.

Make sure when you re-roof to have positive drainage toward the gutter so as to avoid ponding water. A level and string can show how the roof is pitched. Make sure you caulk your seams on top as close to the asphalt as you can get it and caulk with a asphalt compatible caulk, don't use silicone.

All times are GMT -6. The time now is 04:40 AM.