- 1). Measure the entire roof fascia to determine how much soffit and trim you will need. You will need an equal amount of F-channel, trim and soffit. An F-channel is a PVC connector that is shaped like a capital "F." These are hung upside down along the fascia and the house. The soffit panels slide through the two prongs to attach to the house. T-channels are shaped like a "T," and the arms of the T cover the corners of the soffit panels. T-channels are needed only at the point where the panels of soffit meet each other. T-channels are not a requirement. The ends of the soffit panels can be miter cut and placed together. However, the T-channels are easy to use, look professional and are not very expensive.
- 2). Measure the F-channels, trim and soffits to fit each section of the fascia and cut it with the tin snips. The F-channels need to be 1/4 inch smaller than total so the soffits fit into the F-channels.
- 3). Nail the PVC F-channel to the walls under the fascia where the soffit will sit. The F-channels have predilled nail slots that should be used to nail the F-channel in. PVC will expand and contract during harsh weather. To accommodate this, leave 1/32 to 1/16 inch of the nail exposed. Leave 1/4 inch between F-channels. Continue nailing the F-channels to the wall. The most common installation process starts at one corner of the house and works one wall or side at a time, until all F-channels are installed.
- 4). Slide one end of a soffit panel into the F-channel. Bend the panel gently and fit it onto the F-channel on the other end of the soffit. Continue to install the soffit panels until all the eaves are covered.
- 5). Nail a section of T-channel, where the corners of the soffit meet. Slide the ends of the soffit into the corresponding side. Both square and miter cuts work in the T-channel. Squared cuts are easier to install and create less waste.
- 6). Attach the trim to the house. PVC trim is nailed to the top edge of the wall just beneath the F-channel. Make sure to leave 1/16 to 1/32 inch of exposed nail to accommodate the expansion of the PVC. Cover all the edges of the F-channel with the trim.
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