i have aluminum siding on now and will be converting to vinyl with added rigid insulation.
I plan to add 1 inch rigid insulation but the distance between my existing window face and plywood surface is less than 1 inch.

It would seem that my insulation will be left partially exposed, is there any way to deal with this. I dont want to install new windows as these are already new and I son't want use less insulation.

Thanks

Hi craig,

Why not use 1/2" insulation? All you need is a smooth surface. Hopefully, the EXISTING insulation in your walls is 'normal', R-19 (or better.)

I hope you're removing the aluminum first. COnsider caulking around your window and doors and fireplace and such BEFORE you even put up your insulation. And consider taping the insulation board's seams w/Tyvek tape, or something similiar.

My best to ya and hope this helps.

Jay J -Moderator

Hi Jay

Thanks for the feedback.
Initially I had decided on 1 inch, then I measured the walls and noticed the impending problem with the 1 inch sticking out too far.
I then figured no problem, I'll just use 3/4 inch but I noticed that the r value was pretty low (around 3 or so, can't remember).

I live in a northern climate so I am concerned that 3/4 give much more warmth, so I'm trying to find a way to get back to 1 inch.

Yes, I am removing the aluminum first as well as caulking as needed.

Thanks

Hi craig,

Yes, the 1/2" insulation will give you R-3, give or take. HOWEVER, if THAT is all the insulation you have, you'll want fresh insulation blown into your walls. And after you demo the outside wall, that would be a GREAT time to have it done.

Now, assuming you have good insulation in the walls now (which you didn't respond to from my reply), you only need a flat surface. Hence, I suggested 1/2" vs. anything thicker. THen, problem solved!

So, what do you have for wall insulation now???

Jay J -Moderator

PS: If you have R-19 or better, go w/1/2" insulation, and be done w/it. Yes, more is better but, obviously, it will give you problems AND possibly look like crap ...

Craig,
I have run into this same problem, We solved this by wraping 1x2 wood trim around the windows and doors and covered this with aluminum "L" flashing. We butted the insulation board to the wood trim them installed our "J" mould on top. When we were finished we caulked and painted the aluminum egge that showed.
If you use a product like R-Max by celotex 3/4" is an R-5.6 do not use 3/4"styrofoam as its like an R-2.