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How To Insulate Thermally Modified Siding and Rainscreen

Insulating your newly installed thermally modified siding and rainscreen takes a little effort, but the cost of these materials will offset the minor inconvenience. If you are unsure of what to do when it comes to insulation, this article tells you all about how to insulate thermally modified siding and rainscreen.

Cut around perimeter

To make it easier for your insulation material to wrap around tightly and therefore retain heat better, cut two strips each about 4 inches wide outside of the edges of your siding and rainscreen panels as far away from the house as possible. These will provide an area where you can wrap the insulation material around the wall.

Cut vapor barrier

Cut the vapor barrier to size. This step is only necessary if you have installed a vapor barrier on your thermally modified siding and rainscreen Rainscreen. It is not necessary when insulating a solid foam insulated home or even one that has foam board siding panels. Be sure to cut it so that it will wrap around your walls and overlap with the edges of the exterior siding material by at least 1/2 inch.

Attach insulation

Attach your chosen insulation material to the back of the outside walls using a stapler, brad nailer, or screwdriver attachment on an electric drill. Be sure to staple or nail the insulation material to the studs. Nail it so that it overlaps the stapled edge of the vapor barrier material by at least 1/2 inch.


Start with one side, roll up the insulation and vapor barrier material, then use duct tape or equivalent to hold everything in place. Keep going around your house until you reach the corners of your siding. Overlap each side by at least 1/2 inch and secure with duct tape or similar fastener. Be sure to keep everything tight enough so that air cannot leak out of it.

Caulk your siding

Following your insulation, use a caulking gun to caulk along the insulating material. Caulk around your exterior siding and rainscreen so that it holds everything in place tightly, but allows air to flow around it easily. You can caulk around the boards as well, but you will have to repeat the process on a regular basis and it is more difficult to get rid of.


To make sure that your new siding and rainscreen doesn’t move during extreme temperatures, use a DAP caulking gun to seal it off from any air leaks. Make sure that everything is good and tight before you seal it completely. You can skip this step if you don’t care about airflow, but it is definitely necessary for any indoor home.

Check for holes

Check your work by running a light through the wall after you have finished, especially in corners and around windows and doors. If the light is able to shine through, check each area carefully with a flashlight because there could be a hole that needs to be patched with some drywall compound. If you are unsure of how to patch holes, you can use masking tape or duct tape to cover the area and then paint over it.

Clean off the siding and rainscreen

Clean the siding and rainscreen panels by rubbing off any dirt, dust, or debris left over from construction. Make sure to clean any tape or insulation material that is left over from the installation process.

Once you are done with all the steps on how to insulate thermally modified siding and rainscreen, you can go ahead and enjoy your newly renovated home. Contact Sherwood Lumber today and get the best performing siding and rainscreen. Our Americana siding and rainscreen is one of the best brands for your renovation project.