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madmaxmedia 03-08-2009 01:21 PM

Need help with leak and mold through patio roof
2 Attachment(s)
Hi everyone,

We have a covered patio with roll roofing. We recently noticed mold on the wood ceiling.

I went up on the roof and took some pictures. I believe the roof has a slight pitch, and it has gutters that collect rainwater. The roll roofing itself looks fine, but to my eyes it looks like water might be collecting and leaking through where the patio roof meets the house roof. You can see where the roll roofing has raised where water has collected, but again I don't think the leak is through the roofing material itself.

The mold isn't too extensive yet, and I have started treating the ceiling with vinegar, and will later sand down and re-paint with mold-resistant paint.

For the patio roof, I am thinking I can simply better seal the patio roof/house roof line. It looks like whatever was applied has cracked and peeled. I am hoping to not have to rip out the existing roll roofing- I think if I sufficently seal the roof up top and kill the mold down below, the wood ceiling will slowly dry out and I will prevent future mold from growing.

I've attached a couple of pics that hopefully shows the problem. Any advice or suggestions would be greatly appreciated! :)


handyguys 03-09-2009 10:26 AM

I cant tell for sure - That rolled roofing does NOT look like the correct material for a flat, or near flat roof. Even if it is, it is not installed correctly. There should not be all those ripples. Also, its obvious you have standing water. The flashing also looks shot (flashing is the transition between the shingles and the flat roof.

The BEST solution would be a new roof, done by an expert in flat roofs.

No sense painting, and removing mold, until the roof is fixed.

BTW - Bleach, not vinegar, to clean the mold.

inspectorD 03-09-2009 03:36 PM

I have to agree with Handyguys. The roof really needs to be replaced. Those rolled roofs last at best 5-10 years. Yours unfortunately is in need of replacement from the looks of your picture.
And check the status of your plywood and framing underneath, if the wood on the bottom looks that rough, the stuff which is hidden may be in worse shape than you think.
Hope it is only minor damage.:)
A better material would be a rubber roof, they will last 20 or more.

handyguys 03-09-2009 04:35 PM

Thanks InspectorD - There are some roofing materials that come in rolls that are good for flat roofs. The rolled roofing they sell at the home center is NOT for flat roofs. Thats what you have I think.

Are you looking to do a DIY repair or hire it out?

if DIY, do your research and go with a rubber roof, one piece. if you hire it out they may use a rolled roof like modified bitumen but thats not a DIY job. It involved heat and can easily burn your house down if you screw up. There are some newer cold applied rolled stuff but they are a pain to work with. heck, rubber roofs are a pain too. All flat roofs are troublesome if you have low spots (you do) and if you have roof penetrations (vent pipes) or flashing (You do).

So, unless you are a super duper DIYer I think its time to call a roofer.

madmaxmedia 03-09-2009 08:26 PM

Hey guys,

Thanks for all the info, I really appreciate it.

The large white patch you see on the roof was actually the result of me pouring some vinegar where I thought the water might be leaking through. Other than that, I'm not sure if there were any clear signs of standing water (please correct me if I'm wrong.)

I had tried vinegar because I read about how it was very effective at killing mold and bacteria, but safer than bleach.

I would like to do a DIY repair, don't really have the money to properly do it right to be honest. But it is at least 5 years old. I am going to have to sit down and try to plan things out.

How would I replace the flashing? If that is the main source of the leaks, then for the immediate time being I would like to fix that.

inspectorD 03-10-2009 03:46 PM

If you are short on funds I can understand your dilema.
At this point, all roof openings need some sort of tar to patch the holes and nails if you are not going to replace the roof soon.
You have some low spots and some flashing which needs to probably be lifted up at the bottom, and some tar put underneath , then press it down.
Tar comes in 5 gallon buckets:eek: and will work for the year,use a trowel to spread it around as you need to.To some this is a band aid solution and a temporary and unsightly remedy. However it is better that the place deteriorating and falling down in the next few years.
Please be careful up there, that roof does look like it has some bad areas.

madmaxmedia 03-10-2009 04:24 PM

Thanks inspectorD, I think that is exactly what I will do for the time being.

No one can actually see the top of the patio roof anyway, except for maybe Google Maps.

I will definitely exercise extreme caution, that is very good advice.

GBR 03-19-2009 06:23 PM

The spot that is leaking, about 2' from your outside beam, is probably from a nail head above. Your roll roofing needs all the nail heads and material bumps small openings covered with tar (box stores sell it by the tube for a caulking gun, if easier).
Judging from the gap between the beam/rafter, looks to be a 3/12, if so, is acceptable for this type roofing. If you ever re-do it, another coverage is 18" (double lap).
The patio/house joint needs attention. Using the house roof joint - one above the existing flashing, I would re-flash with roll metal 12" wide or so, installing the top edge under the hose roof as far as possible. Maybe even pulling some existing hidden nails, and re-nailing, with tar over the heads. Nail the metal bottom about 4" on center, with tar between, and over those heads.
I have a similar roof on my house, every year I re-tar, for the last 10 years. (I have the ridges too - installed when cold out. Be safe, GBR in WA

madmaxmedia 03-21-2009 06:22 PM

Hey GBR,

Thanks for your reply. I initially figured it was from a leak right above the spot, but it didn't seem to be the case when I went up there. My pictures don't show it too well, but it looked like the water was collecting near the roof and then running down above the beams.

I bought a gallon of rubberized tar for patching leaks, and went up last weekend. I covered up the seam where the flashing is pretty well. I also checked out all the nails and roofing right above the spot, and tarred that up too just in case (including the nails.)

I am going to go up again and check out all the nail holes though again over the entire roof. I am probably going to end up going up once a year too just like you. It didn't take that long, so we'll see how well it holds up, and if the mold re-appears.


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