Installing Wood Siding Over Rigid Insulation

The illustration below comes from the vinyl siding institute.

Installing wood siding over rigid 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. And other non nailable substrates e g. When installing wood siding over rigid foam sheathing you must protect the siding from moisture and heat buildup and use proper nailing. 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.

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. In fact the two products combined make your home super insulated from outside wind and weather. The answer happily is yes. Wood siding applied directly to foam has a history of failures.

How should wood siding be installed over rigid foam insulation. To siding 1 embedment 3 5 0 5 1 5 1 5. One of the biggest questions homeowners have about house wrap is whether it can be installed together with foam insulation. Cladding attachment over thick exterior rigid insulation peter baker p eng.

I don t think builders should install wood siding directly over plastic foam insulation. The vsi installation manual notes when the fastener must penetrate through a non nailable material such as foam sheathing the thickness of that material. A vented drainable air space keeps wood siding dry and stable. Plus rigid foam insulation applied over the outside walls.

Since foil faced foam is a moisture barrier it should be used with a continuous film vapor retarder on the inside wall. Exterior rigid insulation 1x3 wood furring strips masonry structure 2x4 framing attached to surface of masonry. Cover the house walls with 4 by 8 foot sheets of rigid foam insulation typically 1 2 to 1 inch thick nailed to wood sheathing with 1 1 2 inch broad headed galvanized nails every 16 to 18 inches. Installing house wrap with rigid foam insulation.

It adds up to a robust system. Installation details are key. 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. Method 1 james hardie siding installed directly over continuous insulation c i and other non nailable substrates e g.

What are the risks of installing cedar siding directly over foil faced rigid foam insulation should tar paper or housewrap be used as well.