- Q. Last winter, our siding sub
installed aluminum fascia in very cold temperatures. When the
weather warmed up, the fascia expanded and buckled severely.
What’s the proper way to install aluminum fascia to
prevent this from happening?
A.George Schambach responds: To prevent the
buckling you describe (see Figure 1), fascia should be
installed using a "nail-less" technique. By fastening F-channel
to the bottom edge of the subfascia and utility trim under the
drip-edge, the fascia material is held firmly in place but is
still able to expand and contract with changes in temperature
Using a snap-lock punch, form locking tabs in the top edge
of preformed fascia, then press the fascia into the utility
trim. The tabs prevent the fascia from pulling out of the
utility trim, but don’t restrict movement. Many
contractors form their fascia on site using painted aluminum
coil stock. Since coil stock is thinner than factory fascia
(.019 vs. .024 inch thick), you should form a continuous
locking hem on the top edge and insert this into the utility
To prevent the rake fascia from creeping downhill, the
bottom edge of the fascia should be slot punched, then held in
place with three or four aluminum trim nails driven into the
subfascia. These slots permit the fascia to expand and contract
lengthwise without buckling.
Finally, aluminum fascia should never turn a corner.
Instead, fit a small insert at all inside and outside corners
and break the fascia at these points. The insert provides a
background that prevents the wood subfascia from showing at the
George Schambach is a former siding contractor and a
sales representative for Norandex Corporation in Deposit,