Installing Vinyl Siding Over Foam Insulation

Is the fan fold foam an adequate weather resistive barrier.

Installing vinyl siding over foam insulation.

Vinyl siding must be installed against a flat surface. Installing house wrap with rigid foam insulation. Plus rigid foam insulation applied over the outside walls. A corresponding editor paul fisette responds.

Siding over rigid foam. Vinyl siding can be used in original construction or as a replacement for old siding. It typically is installed over rigid foam board insulation fastened to wood wall sheathing. This type of insulation may change and flatten the specialty built in contour of the panel causing the siding to bulge or ripple.

If the wood siding is beveled or lapped you. Fit the rigid foam insulation snugly and seal all seams with the specialized tape. Before installing vinyl siding over existing wood siding we first install a layer of fan fold foam insulation. Rigid foam will shed any water that gets past leaky vinyl siding.

The answer happily is yes. Below are some of the design details along with the benefits. It adds up to a robust system. This detail is used with both new construction and also with renovation work.

Installing vinyl siding over wood siding wood must be sound. One of the biggest questions homeowners have about house wrap is whether it can be installed together with foam insulation. In fact the two products combined make your home super insulated from outside wind and weather. Apply sealant around windows doors and trim.

The nails have a plastic cap that keeps them from damaging the foam. To secure the foam use two inch cap nails. The foam on the outside keeps the wood frame inside the wall warm and dry in. To be an effective weather resistive barrier though the seams of the fan fold must be carefully taped since any seam can provide a pathway for water to reach the structure under the foam.

Existing wood siding must be in good shape with no rot or mold and fastened tightly to the wall. The by the book answer to your question is that vinyl siding manufacturers require a flat solid supportive surface and limit foam installed under their siding to a maximum of 1 in. Always follow the manufacturer s instructions for installing rigid foam insulation. Installing foam board insulation under vinyl siding today more than ever before homes are being built with foam board insulation installed on the outside of the sheathing and under the siding.

Some people use roofing nails but if a strong gust of wind gets under the siding it may not hold.