ASHRAE Journal - December 2020 - 61

COLUMN BUILDING SCIENCES

PHOTO 6 Bump Out Approach Two. A fully adhered
water control layer is installed prior to the installation of the brick and prior to the installation of the
metal roof over the bay. This type of membrane
is typically " robust " enough to survive the installation of the brick veneer. When the metal roof is
installed over the top of this water control layer
membrane (after the brick veneer is installed), it
does not need to pass through the brick.

to the installation of the metal roof
over the bay. This type of membrane is typically " robust " enough
to survive the installation of the
brick veneer. When the metal roof
is installed over the top of this water
control layer membrane (after the
brick veneer is installed), it does not
need to pass through the brick. The
metal roof is in essence " decorative. " It provides UV protection to
the membrane as well as physical
protection to the membrane. It also
looks good.
In Figure 4 and Figure 5 the brick
veneer is supported by a metal
angle-but with a twist: the brick
veneer is constructed within a metal
" gutter. " The water control layer is
lapped into this gutter and the water
that drains down the water control
layer into the gutter is drained out
both ends of the gutter. The gutter
extends past both sides of the bay
and drains into the wall cavity of the
main walls. The metal roof is then
sealed to the face of the brick.
What about stone veneers? Same
issues, same problems, same solutions. Photo 7 shows a metal roof
sealed to the face of a stone veneer.

PHOTO 7 Stone Veneer Bump Out. Metal roof
sealed to the face of a stone veneer. Bad, bad,
bad.

PHOTO 8 Stone Veneer Bump Out Repair. The
stone had to be taken down and a membrane
installed to connect the water control of the metal
roof to the water control of the wall.

PHOTO 9 Walls Meeting Roofs. Where we have the

PHOTO 10 Regletting Does Not Work. Saw cutting

intersection of a sloping roof with a brick veneer
wall the water control of the roof needs to connect to the water control of the wall. It is necessary to drain the back of the brick veneer to the
exterior. This is not done here. The roof flashing is
sealed to the face of the brick.

Bad, bad, bad. Photo 8 shows the
repair. The stone had to be taken
down and a membrane installed
to connect the water control of the
metal roof to the water control of the
wall in a manner similar to what was
done in Photo 6 with brick veneer.
So much for bays, can it get worse?
Yes, of course. Much worse. Let's
now look at where walls meet roofs
(Photo 9). Here we have the intersection of a sloping roof with a brick
D ECEM BER 2020

a " notch " or " reglet " into the brick and inserting a
" counter flashing " will not do the trick. No chance.

PHOTO 11 Counter Flashing Does Not Work. For the
counter flashing to work it has to be connected to
a through wall flashing that then connects to the
water control layer of the wall.

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ASHRAE Journal - December 2020

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