"Betsy" -0 wrote in message
...
Well, last year I was hell-bent on saving money on heating and insulated
EVERYTHING. I tucked insulation up between the sill plates & the floor.
I
wrapped all the steam pipes in the basement to direct the heat upstairs.
I
put plastic over every window. I insulated every hot AND cold water pipe
where they were accessible. I put plastic over every transom and the
lites
on the sides of the front door.

Lo and behold: today I walked over to the window bumpout to dust and my
stocking feet were instantly cold. I realized: where my old house has a
sort of bay (the 3 front windows and the floor under them jut out so the
room isn't square, it has a sort of built-in bay--I don't know what to
call
it!), THIS part of the floor actually is part of the porch! And there is
NO
INSULATION under it. The dining room does the same thing! YIKES! I must
be just pouring money through those floorboards!

So tomorrow I'm crawling under the porch to see how the joists run and
what
I can do to insulate.

What would you recommend for this application? Would fiberglass or rigid
foam be better? Should it be foil backed? I am worried that anything I
put
up that is outside will be a haven for bugs and wood rot. Is there
anything
I should do to prep the area first? How do I get it to stay in place?

I have a 9 by 12 foot bumpout laundry room with four feet of clearance under
it, and no side walls under that space. I filled it with 6 inch fibreglas
batts, then screwed on 1/4 inch exterior plywood to hold it in place. I
didn't vent the area, since there are crosswinds under there, and
overhanging roof eaves keep rain and moisture out, but I didnt caulk the
seams so some air would get inthere. If there is any chance of rain or
moisture getting trapped , you could use zig zagged wire, or chicken wire
stapled to the joists, to hold the batts in.