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 (Figure 2).
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 (...
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