How to Install Soffits in New Home Construction

Examine the boards along the eave and nail down any loose ones.

Attach an F-channel along the fascia's bottom edge by driving in nails every 6 to 12 inches. The F-channel is used to hold the soffit panels. An F-channel is a strip of trim used to hold the soffit panels in place that resembles the letter F when viewed in profile.

Hold a level across the gap between the top of the F-channel and the side of the house. Mark the location of the F-channel on the house once every 12 inches to provide a guide for positioning the F-channel on the house.

Connect the F-channel to the house by driving a nail through it every 6 to 12 inches.

Calculate the length needed for the soffit panels by measuring the inner edges of the F-channels and subtracting 1/4-inch to allow for expansion.

Measure and cut the panels with a circular saw that has a reversed fine-tooth blade or heavy-duty snips.

Install the panels between the two F-channels, bending them slightly if needed.

Install J-channels placed back-to-back, or a T-channel, in the corners. Cut one edge of the corner panels at a 45-degree angle so they form a 90-degree angle when they meet. Like an F-channel, J- and T-channels are strips of trim that resemble the letters J and T, respectively, when viewed in profile.

Cut a cornice panel to fit over the open ends of the soffits and nail them into position. Paint the cornice panel to match the soffits if needed. You can use plywood, fiberboard or metal for the cornices.