We pay as much attention to the quality of our exterior trim as we do the interior trim on the upscale houses we build, so we don't want to see ugly strip vents or round metal button vents messing up the soffits. Instead, we've come up with a nice-looking detail that provides plenty of roof ventilation without calling attention to itself. The vent is concealed behind the 3 1/2-inch to 5 1/2-inch-wide crown molding that typically installs between the fascia and soffit on our homes.
First, we install a pre-primed 1x10 fascia board with a 2-inch gap at the top edge between it and the finished soffit. The soffit paneling is held back from the fascia by an equal distance. Rafter tails or any other framing visible in this gap gets spray-painted black. Using a 10-foot Porta-Brake, we bend 6-inch-wide strips of standard black aluminum insect screening into a U-channel configuration with a 1/2-inch-wide bottom bend. We limit the lengths to 5 feet, because longer strips are unmanageable. The back face of the screen is stapled to the fascia with the bottom bend following a chalk line and the front face left unattached. Next, we cut 1 1/2-inch by 3-inch spacer blocks from 1/2-inch pressure-treated plywood and spray-paint their bottom ends black. The blocks are inserted in the screen channel at regular 16-inch spacing, butted up against the soffit, and nailed to the fascia. Over the blocks and screening, we nail a second fascia member, ripped to drop 3/4-inch below the screen edge. The crown molding installs last, on top of the ripping. The only sign of the vent is a 1/2-inch-wide, uniform gap between the first and second fascia members.
John Seifertis a principal owner of Seifert Construction in Mattituck, N.Y.