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Extending roof on gable side?

I have an attached garage. Gable roof above overhead door. Roof is flush with siding. When it rains I get water behind the vinyl siding and in turn water drips from the header of the OHD. I was wondering if extending the roof would help? I am at a loss here. Plus I have 2 other gable ends with a flush roof and I'm worried that water is getting in there too but I just can't see it. I already had to replace the lower half of the front of the garage due to carpenter ants and water damage when we moved in about 3 years ago. Any advice would be greatly appreciated. Thanks Guys!

MLB Construction
Re: Extending roof on gable side?

sounds to me like a very typical problem which is encountered when covering old clapboards or shingles with vinyl siding and not removing the old siding down to the sheathing.

what's behind your vinyl siding?

A. Spruce
Re: Extending roof on gable side?

One of the many reasons why you will never hear a good word about vinyl siding from me.

In answer to your question, yes, you can extend the gables, however, this would not be a project for the average DIY'r. The reason being, you need to have a working knowledge of structural framing and roofing.You will also be working at height in precarious positions. These are not abilities that the average person tends to have.

Re: Extending roof on gable side?

Just for your info: In my city, a permit is needed for what you want to do. It could be the same in yours.

A better approach would be what the two gentlemen suggested above.

Re: Extending roof on gable side?

Overhangs are more than styling- they perform a function in protecting the top of the siding from the weather. You might be able to seal this area better with silicone caulking which is flexible enough to work with the vinyl siding, but that's a patch- not a real 'fix'. You do need to do something though as water behind the vinyl will lead to a repeat of what you had to fix before so if you can't have an overhang constructed then at least caulk above the top J-Channel which is probably where most or all of the water is entering, and look for any other possible entry points and get them as well. Flush overhangs are a serious mis-design with normal frame houses!


Re: Extending roof on gable side?

Another fix that doesn't require as much work as extending an overhang is to use a 2x trim board or two along the rake of the roof. It would involve cutting back the siding, adding a new drip edge along the rake and back under the shingles. This can be done without modifying the shingles probably. Covering the new rake with aluminum and proper flashing should keep water from getting behind the siding.

To add an overhang, even a 12" ladder frame attached to the existing end truss/rafter requires removing some roof and sheathing so new plywood can be extended back at least two truss/rafter bays to tie the new frame extension into the roof. Adequate attachment of the frame with lags or bolts is needed.

A final thought, can just a new drip edge to overlap edge of the siding be installed. This would certainly be the easiest fix.

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