Thickness of rigid insulation
Domenick
| Posted in General Questions on
I am planning to replace the slate siding of our house with clapboard vinyl siding and I want to install 1/4″ or 1/2″ rigid insulation. What if the rigid insulation will make the J-channel protrude on doors & window jambs? Is there a way to fix these?
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Replies
Domenick,
Any experienced vinyl siding installer will know how to trim windows, even if the job includes 1/4 inch fanfold insulation. The thicker the rigid foam, the trickier the details. If you decide to go to a full 2 inches of rigid foam, you'll need exterior jamb extensions and flashing at the window sills.
If these finish carpentry terms are new to you, and you are doing the work yourself, you might want to hire an experienced contractor to do the work, or spend some time learning how exteriors are trimmed.
Domenick,
Below is a photo of a replacement window job with J-channel that is proud of the old window trim. Some people don't mind the look; others hate it.
If proud J-channel bothers you, you can disguise the issue somewhat by installing a wood trim piece around each existing piece of exterior window casing to fatten up the existing trim before installing your J-channel. That way your J-channel will no longer be proud. However, you have just added a wooden exterior component that will need to be painted or covered with coil stock, so there is a trade-off.
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