Installing Wood Siding Over Rigid Insulation

Installing house wrap with rigid foam insulation.

Installing wood siding over rigid insulation.

Gypsum sheathing with combined thickness of 1 inch or less method 2 james hardie siding installed to furring strips that are attached through the c i. A vented drainable air space keeps wood siding dry and stable. What are the risks of installing cedar siding directly over foil faced rigid foam insulation should tar paper or housewrap be used as well. One of the biggest questions homeowners have about house wrap is whether it can be installed together with foam insulation.

The illustration below comes from the vinyl siding institute. Plus rigid foam insulation applied over the outside walls. I don t think builders should install wood siding directly over plastic foam insulation. Nailing wood siding directly to foam doesn t work because nails have to be extra long to reach through the siding and foam to a solid nail base.

Wood siding including cedar siding should be installed over an air space regardless of the type of sheathing used. Exterior rigid insulation 1x3 wood furring strips masonry structure 2x4 framing attached to surface of masonry. Cladding attachment over thick exterior rigid insulation peter baker p eng. How should wood siding be installed over rigid foam insulation.

Installation details are key. When installing wood siding over rigid foam sheathing you must protect the siding from moisture and heat buildup and use proper nailing. Julie the installation instructions of the vinyl siding institute and most if not all vinyl siding manufacturers allow vinyl siding to be installed over rigid foam sheathing. To siding 1 embedment 3 5 0 5 1 5 1 5.

Moisture protection and heat buildup. It adds up to a robust system. In fact the two products combined make your home super insulated from outside wind and weather. With foam sheathing an air space is essential both to reduce the siding s water uptake and to provide a.

And other non nailable substrates e g. The vsi installation manual notes when the fastener must penetrate through a non nailable material such as foam sheathing the thickness of that material. The answer happily is yes. A homeowner in southwest virginia wants to install engineered wood siding over exterior foam insulation but finds that the manufacturer s installation instructions raises concerns he hadn t thought of.

Since foil faced foam is a moisture barrier it should be used with a continuous film vapor retarder on the inside wall.