Insulation under lap siding on the west side of a house
alpine365
| Posted in Energy Efficiency and Durability on
I am changing out the siding on a 1987 house that has a tyvek layer. With window trims I do not have space for a think insulation thus can only use a 1/8-1/4 inch thickness This is at 5600 feet on the west side where there is a lot of afternoon solar gain. Is there a thin insulation (possibly with a reflective coating) that I can put between the Tyvek and the siding that will help block summer heat. It would also be great to help keep in winter heat. House is located in Colorado any comments are appreciated.
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Replies
Mark,
I'm sorry, but the laws of physics are against you. Unless you are willing to invest in extremely expensive materials like vacuum-insulated panels -- which, by the way, are experimental and fragile in addition to being expensive -- then you are limited to materials that have a maximum R-value of about R-6.5 or R-7 per inch.
To make much of a difference, you need several inches of insulation.
Mark,
Fortunately, window casing is removable. As long as you are willing to install exterior jamb extensions and sill extensions, you can add thick foam to your wall. For more information, see How to Install Rigid Foam Sheathing.