foam under vinyl cedar impressions
I’m looking to reside my house with the cerrtainteed cedar impresssions siding. I’m debating wether to put foam on the walls or not. I don’t want to bury the windows and doors and I don’t want to reset them. I was thinking I can live with a compromise of 1/2″ foam. I have 2 x 4 framing. Some rooms I have done over and re-insulated with r 13 batts but some are origional 2″ fiberglass that has most likely sagged.
the house is circa 1950’s and in my opinion, payback on investments will be limited since every house on the street looks the same. My question is: would 1/2″ rigid foam be worth the effort? second – what type of foam would you all recomend? I know the cedar impressions are very temprature sensitive so I’m leery of the foil face stuff that might reflect the heat back to the siding. (is that even a legitimate concern?)
thanks in advance!
Jason
PS – If I do go foam do I omit the wrap and tape the seams?
FYI – I’m in the lower part of New york state.
“it aint the work I mind,
It’s the feeling of falling further behind.”
Bozini Latini
Replies
Are you siding over existing siding, or removing the existing and siding over flat sheathing? Understand that the thin fan-fold foam "insulation" that's commonly used in siding-over jobs is just used to produce a flat surface -- the foam is about the cheapest available material for doing that, and as thin and poorly sealed as it is it provides negligible insulating value and little protection against air infiltration.
With a typical 50s house, sealing against air infiltration (eg, with housewrap) will provide more comfort improvement and reduction in heating costs than another 1/2" or inch of foam. Of course, if you can do both then so much the better. (Note that sealing is doubly important if you'll be removing existing solid siding and replacing with vinyl -- vinyl provides virtually no protection from infiltration.)
Dan, Thanks for the reply. I will be removing the siding (old cedar shakes that are brittle, breaking, missing etc.). I will also be removing the tar paper wrap on the building.
there are some bulges in the plywood so I will need to re-nail / screw that as well.
I usually use typar and seal the windows / doors with grace vycor. all the windows have been replaced over the years and are sprayfoamed. one quirky thing going on is that my radiators (hot water) are recessed into the wall thus having no insulation behind them. very strange idea from the origional builder. I was thinking at the least the foam would reduce heat loss in that situation.thanks,Jason"it aint the work I mind,
It's the feeling of falling further behind."Bozini Latinihttp://www.ingrainedwoodworking.com
I did my house last year. Same scenario with the heat being recessed.
I went.. house wrap, 3/8 fanfold, Cedar impressions. If I had to do it again. I would go with alcoa's version of impressions. The lock is continuous and they have a larger color selection.
for a guy who's screen name is "TheButcha" you did a very nice job.
Did you notice a difference in your heating last winter?"it aint the work I mind,
It's the feeling of falling further behind."Bozini Latinihttp://www.ingrainedwoodworking.com
The R-value on the fanfold is next to nothing. I used it more to get a smooth surface to hang the siding on. What I do notice is no draft. The first floor of the house has no insulation in the walls. I did shoot expandable foam in between the sills and the top of the foundations and stuffed fiberglass batts against the box beam. This made a HUGE difference in my basement. The 2nd floor I added. You can heat it with a match. I thought my heating and cooling bill would be 40% more but it turned out to be only around 20%.
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Edited 9/25/2007 5:57 pm ET by TheButcha
Nice job. You did wrap under the 3/8 foam right.
Thanks.Yes sir. The white border is a 2x6 nailed to the box beam (rim joist). I wrapped the house first, then nailed the 2x on, followed by cutting the wrap and cladding the 2x (incorporating a drip cap) and lapping the wrap over my cladding.