[Greenbuilding] Insulation, windows, siding...oh my! (Take 2)

[Justin Close]

(Hmm...trying again but sending it as plain text this time.)

We are looking at doing some improvements to our home here shortly.  We 
have a number of things that need done, and some are just a bit more on 
the "want" side, although still very important.

Anyway, we are looking at redoing the roof & gutters, rebuilding the 
chimney (from the roof up only), replacing the siding on the house, 
insulating the walls, replacing the water heater and replacing the 
windows.  And I am already in the process of replacing/updating the 
electrical system.  It is a 1950s ranch (1955 I think) with many of 
these systems probably original to the home.

We have talked with a few roofing contractors to get estimates.  One of 
them suggested leaving the current roof, putting foam insulation over 
it, and then reroofing.  We currently have some insulation, rather 
inadequate though, in the attic area.  Would this double layer lead to 
problems?  What about having the good insulation layer at the roof level 
instead of at the ceiling of the living area, just in terms of an 
efficiency aspect?  I have been thinking that we would have them remove 
all of the current attic insulation and reapply something new and 
uniform (foam?  cellulose?).  And while it is exposed it would be a 
great time to rewire things!  :)

For the wall insulation we currently have zero.  These are 2x4 stud 
walls, 16" OC.  Exterior wall sheathing is an odd version of particle 
board, it appears:  It is rather coarse material that isn't very dense 
nor glued or pressed together very strongly.  Then there is a paper 
layer of some sort.  Most of the weather-shell is shingle.  But there 
are areas of the front that are brick about half way up, then topped 
with T-111 type paneling.  It is an odd mish-mash.

Anyway, I mention all of that because my thought is to remove the siding 
and sheathing, do some rewiring while it is exposed, then do some 
insulating, replace the sheathing (perhaps use new stuff?), and put up 
new siding.  (The current shingles are all rather warped at the vertical 
edges, and I question their effectiveness.)  If we did it this way I 
have been thinking I would use some expanding foam insulation in the 
walls:  firstly, to achieve good insulating values, secondly to provide 
for air sealing.  (Our house is rather permeable.)  But I realize that 
isn't the greenest material out there.  Also, now that I am exposing the 
stud bays, would it make sense to go around and in some manner add on 
some more studs to achieve a deeper bay?  And what to use for siding?  
Certainly not vinyl, but what about hardi-board type materials?

I have also thought to insulate under the floor, again with expanding 
foam for air sealing purposes (not so much for insulation value, but 
just to seal the house from the crawl space).  We have had a few 
interesting experiences with things go wrong in our crawl space, and 
that has lead us to realize how much air penetration we get through the 
floor.  It is just 2x10 sub floor (on top of the joists) with about 1/2" 
gap between each board, and then the wood finish flooring of the house.

Windows:  I have read many a thread here about windows.  I don't like 
vinyl myself (vinyl is evil!), but it can also be so much cheaper...  :(
We have 11 windows in total, if I count correctly.  A number of those 
are odd sizes, though, and to the larger end of things.  Our current 
windows are all aluminum, double pane.  They are cold and sweat a lot 
during the winter.  The ones in the bedrooms are all rather short 
(perhaps only 3' high?), high (bottom of window is about 4' from the 
floor), and more normal sized.  There is one large one in the living 
room, perhaps 5' high x 8' wide?

We were thinking of just getting a high efficiency electric water heater 
as a replacement (current one is electric, too).

And on top of all of this the daughter wants to go to college this fall, 
so budget is a big concern!  I would love to be able to do things right, 
but that is usually the more expensive route, too.

Whew!  Thanks for all your advice.

--  Justin