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Fix roof leaks in minutes | Broken Shingle | Roof Jack Gasket | Two common easy to fix leaks

Black mold on the under side of roof deck show a roof leak.

Black mold on the under side of roof deck show a roof leak.


Leaking roof? It may be easy to fix. Do some investigation before calling in the expensive contractors.

Fixing a leaking roof jack seal

A roof jack is the flange and gasket that slides over the sewer vent pipes exiting out the top of the roof.

Most of the gaskets are made out of rubber which will eventually dry rot from summer heat, sometimes in less than 8 years.

The base is made of plastic and will tend to last for the life of the roof. Some of the older roof jacks are made of metal with the rubber gasket.

On the initial break down of the rubber a small crack may be the only problem, this can be easily spotted and sealed with silicone to last a few more years.

Some roof jacks are made of lead with the outside that covers the pipe coming up. The top is then bent over the edge of the pipe and down into the sewer vent.

Occasionally the top edge of the lead that is bent over the pipe edge will crack and break open. This can also be easily fix with silicone.

The roof jack is designed to elevate the gasket up off the roof and out of the direct path of the main runoff of water flowing down the roof.

Unless you have a roof jack that is on a fairly flat roof the chances of water building up this depth and actually flowing in from the roof runoff is slim.

Although the factory made roof jacks have the rubber seal bonded to the flange, the rubber seal mainly just seals off the rainwater that is hitting the vent pipe and running down it. This is similar to the rain collar used on gas vent stacks.

The key solution is to seal the vent pipe penetration so the rain water hits the side of the vent pipe and seal but then continues to run on down the flange and shingles instead of following the vent pipe on inside the house.

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Some are totally convinced that the only way to fix a leaking roof jack gasket is to replace entire roof jack, meaning it has to be removed and replaced with a new one.

After doing one and damaging the shingles, we have since discovered a more simpler way to make this fix in less than 10 minutes without having to tear out the old roof jack at all.

We have used this on our own Texas roof over the past 10 years with no further leaks. The house is 17 years old and in the hot Texas summer heat we have had to fix several of the roof jacks when the rubber gasket totally failed.

The problem is that these roof jacks are put on during construction, nailed down and then shingled around.

Even though they slide up under the shingles. Trying to remove the nails and then sliding the old roof jack out and up over sewer pipe is nearly impossible without breaking and damaging the shingles around it.

Some of these shingles may last another 10-20 years, cracking and breaking them is just not the best option as it creates such a potential for even bigger leaks.

The solution is so simple that we can’t believe it is not sold separately. Go ahead and purchase a new roof jack for the size range for the vent pipe, they are rather inexpensive under $10.

Instead of trying to take off your old roof jack simply cut the rubber gasket out with a sharp utility knife, silicone around the base of the old gasket and slide down the new gasket with another bead of silicone added around the rubber and sewer pipe to seal it.

Be sure to cut out the complete rubber gasket so that it will fit to the edge on the old base and allow the rain water to flow on down to the base of the flange.

Throw away the base of the new roof jack and you’re done.

For those who are still convinced that the roof jack has to be replaced, well been there done that! This sure beats damaged shingles and hours to replace one.

As long as the water runs off the gasket and down on to the roof is all that really needs to be accomplish.

Depending on the size of the hole or crack in the seal, rain water can actually leak down into the wall and be absorbed by the drywall for months and years before showing water damage outside the wall.

All this moisture is a problem waiting to happen either with growing mold or inviting termites up inside the walls.

A leaking sewer vent can also mimic other plumbing leaks in upstairs bathrooms in two story homes.The vent pipes flow down directly into bathroom plumbing and down through the ceiling below.

A good annual roof top sewer vent inspection and fixing the gasket is really a good investment in time.

Fixing a broken or cracked shingle

A broken or cracked shingle either caused by a hit of a misguided baseball, hail, or a windstorm can also cause a leak. The shingle(s) that have become cracked allows water to seep down into the underlying shingle joints or nail heads that would otherwise be covered with the shingle.

Finding these problems may be a bit more difficult as a shingle may only have a hairline crack allowing water to seep in. Water can actually travel great distances down along rafters before hitting a barrier that then causes it to drip on down on to the sheet rock ceiling below.

If you begin seeing a black spot or a spot on the ceiling where the paint and plaster are peeling, it's probably because a roof leak has developed.

To investigate a leak take a tour of the area up in the attic. look for the signs of water tracks and stains.

Don't be alarmed as some of these areas may have occurred during a downpour while the home was being constructed before the actual shingled roof could be applied.

A persistent leak will show signs of black mold in the area. In the picture of the attic it was pretty quickly identified that this leak was coming directly above the water damaged ceiling in the garage.

This area of the ceiling is not insulated so it was very easy to see what has been occurring although the ceiling in the garage only had a quarter size plaster peel.

A close inspection of the shingles above this area quickly identified a broken shingle. This is also a 10 minute fix.

By carefully lifting up the shingle on each side of the broken area we carefully added some roofing tar to a piece of flashing and then slid it up and under the upper row of shingles and the sides in order to span the space that the original shingle would cover.

A putty knife might be needed to carefully break loose the self seal tar strip under the front edge of the shingle.

The metal flashing is cut just the length of the shingle plus some, so that when installed it will extend up under the upper shingle row but it won’t be seen from the ground.

Any water that seeps through the crack will then flow under the shingle onto the flashing and on down the roof.

Just a dab of roofing tar is then added on top of the flashing carefully not to allow it to ooze out on top of the shingle where it has been cracked.

This will then secure the broken shingle down and hold the flashing in place during future wind storms. When finished it should not be readily noticeable even when up on the roof.

If too much tar is used it may actually build up a ridge under the shingle and divert water off to one edge to another shingle overlap or nail head.

Even if the shingle completely broke and blew off during a wind storm, it is likely close by in the yard or in the shrubbery.

Finding it and replacing it using this flashing method will be better than placing a new shingle over the spot. Adding a new shingle will likely stick out like a sore thumb.

Pictures are courtesy of Cottage Craft Works .com finding solutions and products for the old fashioned self-sufficient lifestyle.

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