On Dec 2, 3:29*pm, "Kevin" wrote:
I'm thinking to cut to fit pieces of 2" polystyrene for my shop windows for
use in the winter (east and west) and summer (south). *These are double hung
windows with a good 2" recess where the foam should fit in fairly well.

Other than it being 'pink' - it should be about an R10. *One sheet should
cover 3 of my 4 windows and hopefully significantly reduce the amount of
hours on my electric heater.

This is for my "office-side" of the insulated shop. *23x11 with a 220V
heater. * Four 34 x 44 windows.

I was also thinking to spray adhesive aluminum foil to one or both sides
(sun exposure side in the summer).

The sheet was $24 and should be enough to cover 3 windows.

Thoughts?

Had the same idea, but to cover storage room windows on the
upper floors where I don't need sunlight. I'd cut the panels 1/4"
or so undersized and cover the edges with foam weatherstrip
tape for a good seal. You might want weep holes top and bottom
to prevent overheating or condensation.

Replace the foam with black painted plywood, and
you've got instant solar panels to further cut the load
on your heaters.