Sunday, 18 October 2015

Sometimes complicated is not as good as simple

Sometimes complicated is not as good as simple - water heater leak pans.

Posted: 15 Aug 2015 06:21 PM PDT

Everyone knows that it is a good idea to install a leak collection pan under water heater. In fact these
pans are required by modern standards whenever the water heater is installed in a location where
damage could occur if the tank were to leak.

At a recent inspection I found the water heater in the following picture installed behind some removable
panels of a cabinet located in the bathroom.


With the panels out of the way one can see the plastic liner that has been created to form a pan
for the water heater.


The white pipe on the right in the picture (that terminates inside this pan) is the drain for the
Temperature Pressure Relief Valve (TPRV). In some jurisdictions around the country this pipe
is allowed to terminate in the pan but it still must have an air gap. With an air gap, the end of
the pipe would never be under water if the pan were to flood. If the end of the pipe was under
water the relief valve might not function properly.

In Washington State, which follows the Uniform Plumbing Code (UPC), the TPRV drain cannot
terminate at the drain pan and must go to a proper drain receptor or to the exterior of the building
at an approved location.

Another component of the leak pan is that it should have a drain so that any leaks can be safely
drained away. If the pan cannot have a drain, then a high water alarm is recommended. Keep in
mind, these pans, even the very unusual high pan in the picture above, would never hold the
quantity of water that is in the tank after the water is shut off. If the water is not shut off it would
not take very long for a significant leak to flood over the top of the pan.

Whoever installed this water heater had a more complicated means of dealing with monitoring for
water in the pan. A glass "viewing port" was installed so that it could be viewed while sitting on the


Sometimes complicated is not as good as simple.


By Charles Buell, Real Estate Inspections in Seattle


Sometimes it is the little details that make all the difference -
know when to be flashy and when not.

Posted: 07 Aug 2015 06:33 AM PDT

Today's post is about one such little detail. In this case the risk of its being a "big deal"
is small but I have seen similar installations where, over time, considerable damage
does occur.

This is a typical lead flashing common on houses in the Northwest.

Lead Pipe Flashing

Lead Pipe Flashing

The flashing is made of lead. It is designed to fit over the pipe and be lapped by the shingles
on the plane of the roof. The cap you see on the top is a nice way to finish off the installation
and is quite common when the roof portion of the flashing is not quite tall enough to extend to
the top of the pipe. When it is tall enough, the excess above the pipe is simply folded inside the
pipe. When the top is "counter-flashed" with this type of cap it is designed to lap both the outside
of the lead flashing and the inside of the pipe. Without the cap, any water that hit the pipe would
run down the pipe behind the lead flashing.

Now you might ask, well how much water could that amount to really?

If you look at this next picture you can see where the blue arrow points to two water lines that
show how water hitting the inside of the cap is still finding its way outside of the metal flashing.
The red arrow points to a water line that is clearly running down the pipe and into the roof/house

Lead Pipe Flashing

Lead Pipe Flashing

In this next picture we can see "why" this is happening. When they installed the nice
counter-flashing the piece that is supposed to be inside the pipe got scrunched and
no longer directs water inside the pipe. While the blue arrows show where they have
been "lucky," the red arrow show where they have not been lucky.

Inadequate Lead counter-flashing

Inadequate Lead counter-flashing

In our area of the world, where it can rain or drizzle for weeks on end, it actually can result
in a fair amount of water getting into the roof/house structure. Sometimes these vent pipes
make an immediate right angle below the roof line to move over to where the pipe actually
comes up through the house. There are lots of reasons why a plumber might do this. For
example if the pipe would end up coming through the roof on the "street side" of the home,
they will often run it to the back of the house where the pipe would not show.

At any rate, even a half a cup of water a day–or any amount that would not dry in 24 hours
would keep ceilings below the leak wet and eventually cause damage to the ceiling. As a
Licensed Structural Pest Inspector, this lack of attention to detail is what we would consider
a "conducive condition." A condition that if left un-repaired could result in wood decay/rot or
promote infestation by wood destroying insects.

I have found several damaged ceilings with "unexplained" past/ongoing water damage from
improper flashings around pipes. Repairs are a very easy fix, but certainly worth noting.

This defect, I might add, could likely not be determined from a ladder at the edge of the roof–
and you would have to be pretty lucky with a drone as well–another important reason for the
home inspector to walk the roof when it is safe to do so.

By Charles Buell, Real Estate Inspections in Seattle




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