This siding project in Middletown started out as a handyman service call. The unit owners have had an intermittent leak in their common wall for several years, even after the entire building got a new roof. Once I was up on the roof looking at the wall in question, the reason for the leaking was apparent. The trim was not properly protected and more importantly the siding under the trim was not properly installed. I could see exposed wood showing under the drip metal, and several of the pieces of siding were not in the J channel where the siding meets the roof, not to mention the J channel was full of debris and plant matter, (which is essentially what funnels or channels the water from the siding down the horizontal roof surface). However, once I got the siding off it was obvious that the lack of vapor barrier of any kind on that section of gable wall was the real culprit!

In this section you can see the how the project moved through the different stages of construction. With each major phase or ” STEP” I like to include a gallery, as well as some description of the processes and challenges in that particular part of project.

The first step in the siding repair project was to remove the existing siding pieces, and loosen the drip metal at the roof edge above the bottom edge of the existing metal. After all the siding was removed I was able to clean out the J channel and the roof surface adjacent to the J.

Once I started removing siding pieces and saw that there was no vapor barrier behind the siding I knew that this was a major contributing factor in the leak problem. Intermittent leaking on roofs and and siding surfaces, is usually caused by wind driven rain or freezing and thaw cycles. Why is that? Because all flashing and exterior construction techniques are designed with the principal that water only goes down (because of gravity). But in real life, water can travel sideways and under the right conditions even travel upwards along a vertical or horizontal plane.

How does this relate to the leak you ask? Easy, only during inclement weather conditions, or high wind driven rain will you have water getting in where it normally doesn’t. The conditions on the roof where these two common walls meet are perfect; the dwelling units are townhouse style 2.5 story construction, with an embankment style foundation that walks out to the rear. They were built embankment style because the building is located on a site with steep topography that slopes down and away from the rear of the dwelling units. This creates a condition where winds racing up the hill hit the dwelling units and push water against the siding and back into the trim and into the house, where under nominal conditions it would simply drip down onto the lower roof line, or down the siding pieces and into the J channel.

After the siding was removed was everything was cleaned up it was time to install the new vapor barrier. This is done with staples and I pay particular attention to keep my staples above the step flashing or roughly 4 in above the roof line. Then it was time to make the new metal wrapping that will slip under the existing drip edge, wrap down and under and back up the backside of the facia trim, (think of a U shape). These were made in 10 foot sections and like all flashing (see gravity theory) must be installed from the bottom up, so as to overlap all pieces from the top down. As the new pieces of metal were installed using aluminum roofing nails, the siding pieces were also nailed up again, and set tightly into the J channel so as to sit flatter on the small area of vertical side wall. That was it, the 2nd to last piece was a little two large now that I had rehung all the other pieces, but I left it a little long and face nailed it into the last piece. This ensures that if there is more expansion or contraction I have a piece with some play in it to reset or trim… better left for next time because once you cut it off you cant put it back lol!!