We bought our house with our deck already built on the roof of the garage. The person, who did it, nailed the roofing felt directly through just everything, now it is raining in our Garage. We want to take all the boards of, repair the roof and put the boards back on. My question is, how to do it without damaging the roof again, where/how to fix the support beams. The deck is huge, on top of a 2 car garage.
Kathrin

 

I think my first step would be a visit to the local building inspector's office to make sure it's even legal. You wouldn't want to get a thousand dollars into the project and have the building inspector drive by one day and say "hey, you can't do that".

 

The house was inspected for all kind of things before we bought it. Isn`t it always? I even doubt that the deck builder himself nailed though the roof, because the deck itself was built so perfectly, qualitywise. It is a weird combination. Kathrin

 

It's customary to nail thru the roofing felt when nailing the roofing shingles to the roof deck. Not sure if I'm getting the whole picture, but it doesn't matter because your garage roof is leaking and that's the bottom line.

Is it leaking everywhere, or can you pretty much nail the area down to where it's leaking? Is this a flat roof garage?

When you say take the boards off, do you mean the decking off your deck? The plywood under the felt of a roof is referred to as the roof deck, so I want to make sure we're talking about the same thing.

 

Yes, I mean decking off the deck. It is not raining everywhere, but on several spots. It is a flat roof. Kathrin

 

Well, if you can identify where the leak is by removing the decking, then you should be on your way to a dry garage. Your problem sounds like it's more of a roofing problem than a deck problem, but you do need to know if the way the deck was built is actually causing the leak.

Can you tell what roofing material is used? It could be a rubber roof, or hot mop tar possibly? Depending on what type of roof it is will most likely determine what you use to seal it up.

If the roof is completely covered with the deck, then you'll be better able to hide your patch work and not worry what it looks like underneath. Home Depot sells all sorts of liquid roofing materials for this type of repair. Depending on how big the roof is, you can also look into using Weather Watch Ice and Water, which is usually used to prevent ice damming. I did my entire back porch roof with it before putting down asphalt shingles. I also used it around 6 skylights that I installed and down a valley in my roof. I believe it comes in 3'x50' rolls for around $50. The stuff is great and has a self stick backing.

 

It is some kind of thick "paper", like shingles, but larger. Then it seems to be painted over. The deck is large and covers the entire roof. Kathrin

 

On a flat roof, you wouldn't want to use anything like shingles because water will get in underneath and you'll end up with a leak like you have.

Hot mop tar or a rubber roof is completely sealed. You should look into redoing the roof with a material that will cover the entire roof with any seams completely sealed.