Fiber Cement Siding Over 1 Inch Insulation

When applying james hardie siding directly over the combined thickness of foam sheathing continuous insulation and other non nailable substrates e g.

Fiber cement siding over 1 inch insulation.

Becouse the foam compresses. Fiber cement insulated vinyl. Installing hardie over 1 quot. Of 3 to 3 5 which limits insulation thicknesses to 1 5 max 3 5 fastener to siding 1 embedment 3 5 0 5 1 5 1 5 max insulation therefore for insulation greater than 1 5 direct attachment of cladding though the insulation back to the structure is often not practical.

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. It then pops the nail right through the siding. You didn t indicate where you live but you could use a layer of tyveck paper to allow moisture thru from the inside to the outside and then cover this with lapped 15 asphalt felt to create a seperate drainade plane for any water comming from the rain getting thru the cement siding 1 inch rigid insulation could be applied beneath the siding and over the felt. Measure the walls from top to bottom with a tape measure and buy either 4 by 8 foot or 4 by 9 foot sheets of rigid foam insulation to cover from the roof line of the house to the sill plate at.

I would also consult a local structural engineer to make sure there is not undue force on the fasteners due to gravity load or wind load. Fiber cement offers minimal energy savings at 15 r value but can be installed with fanfold or insulating sheathing products to improve the r value of the whole siding system. Gypsum sheathing up to 1 inch thick the foam sheathing and other non nailable substrates do not have nail holding capacity. One new wrinkle for many builders is walls built with fiber insulation.

With insulation thicker than 1 inch i would consider using wood furring strips on galvanized steel zee girts or hatbars so that you have enough options for proper fastening. I have tried several different air setings for my compressor. I seam to be blowing out the back side of the siding. We put 2 x 4 furring studs laid flat over the foam and attached to the wall studs with 1 5 inch foam between the furring studs rain screen over everything and finally the lp siding.

This only increases the wall thickness 3 4 inch vs the furring strips william costello was planning to use and would only require increasing the interior window.