Installation Video Series, Part 5: Installing LP^® SmartSide^® Soffit

Now that you’ve properly installed your LP^® SmartSide^® trim and siding, it’s time to install your LP SmartSide soffit. LP makes soffit in several designs, including panel soffit and cut-to-width soffit which is available both as vented and non-vented. LP SmartSide soffit can be applied over framing that spans a maximum of 24 inches on center. One thing to remember when installing LP SmartSide soffit is all ends and edges must be supported or backed by solid 2×4-inch or larger framing.

Preparing for Installation

If you are using LP SmartSide vented soffit, try to avoid cutting through the vented areas. Also if you are installing an open soffit application, you must use Precision 76 Series or 190 Series soffit. As with all LP SmartSide products, do not install the soffit in contact with masonry, concrete or brick.

You want to use a minimum of .113-inch shank diameter, hot-dipped, galvanized box-style nail with a minimum of .270-inch head diameter. The nails should be long enough to penetrate the structural framing by at least one and one-half inches. Always set your nail gun so the head of the nail is snug against the siding or flush with the siding surface. Try to avoid overdriving the nails. If you do, seal the hole and exposed substrate with an ASTM C920, Class 25 sealant. If a nail is overdriven by more than 1/8", seal the hole and renail it.

When you cut LP SmartSide products to size, always apply primer and paint to field cuts with a high-quality, 100% acrylic latex paint.

Soffit Nailing Guidelines

Position the soffit so all ends and edges land on studs, then begin nailing. You should nail around the perimeter a maximum of every six inches, and every 12 inches at intermediate supports. When nailing the perimeter, space your nails 3/8" from the edges. When nailing up your soffit, make sure you space all ends and butt joints a minimum of 3/16".