Insulation Over Existing Siding

Vinyl siding must be installed against a flat surface.

Insulation over existing siding. Continuous insulation under new siding has become a popular way to improve energy efficiency on an existing home because it addresses a problem known as thermal bridging. Probably not significant but if you do insulate over the existing siding you have a separation between the insulation layer and the air barrier layer if there even is one. Generally the best idea is to remove any existing siding from your exterior walls before installing the vinyl siding. One major stipulation with the james hardie siding warranty is that it specifically states that if.

Existing wood siding must be in good shape with no rot or mold and fastened tightly to the wall. By installing insulation on the outside of the framing it causes the location of the dew point to move to the outside of the wall assembly. If the wood siding is beveled or lapped you. This goes for fiber cement hardwood and masonite siding.

The exterior insulation also helps keep the siding all vinyl siding leaks further away from the exterior sheathing. I ve always wondered if this compromised the r value of the wall assembly. Removing existing siding and installing osb has several benefits such as having brand new substrate on the home and the ability to inspect the wall cavity and all framing insulation and structural integrity of the home before replacing siding. If you do decide to cover your lap siding in vinyl you ll need to first layer the existing lap siding with highly durable foam insulation and a moisture prevention barrier.

In other cases it must come off. Going over the existing siding adds to the r value by creating an air space between the insulation and old siding. This reduces the likelihood of condensation within the wall cavity. Wrap the house with a moisture barrier usually some type of polystyrene wrap and install desired siding by nailing through the foam board into the house framing.

Keller sons llc roofing siding windows. In most cases you can put new siding directly on top of old siding without having to remove the old siding first and in addition it will in fact add an addition layer of insulation thereby helping lower your energy bill. Most homes in the united states are built with traditional wood frame construction with studs every 16 on center. Foam board is however often added in order to help level out the wall when it has certain problems with it.