Looking for the best way to re-build old gutted house walls in zone 4A.
I have abandoned our original plan to take off the 1883 original in-good-shape-siding to apply a rainscreen and insulate from the outside in because it simply costs too much given the attendant need to re-jigger the soffit and trim. So, leaving the siding on, how would you suggest I most efficiently and effectively still install a gap between the siding the the interior insulation? I’ve seen several options, Mooney wall, the Chautauqua Cottages system/other. Swimming with choices I would appreciate some balanced verdict about a best system for rainscreen, air barrier and insulation. Am willing to decrease interior to a small degree. Thank you Sacie
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Sacie,
We need to know more about your house.
Does your wall have any exterior sheathing? Or is the siding nailed directly to the studs?
What type of siding is on the house?
Is there any evidence of a water-resistive barrier (for example, asphalt felt)?
Does the house have wide roof overhangs or stingy roof overhangs?
Is it a one-story house or a two-story house?
What size are the studs?
Is the interior plaster or drywall in good shape?
Do you intend to do any re-wiring or make changes to the plumbing?
Will you be replacing any of the windows?
Thanks Martin for your many questions.
1. It is not clear to me whether the house has sheathing or not. We have only just begun gutting it. After the weekend I will know for sure. I don't think it does, however it is difficult to tell at this point.
2.The siding is original 1883 clapboard, probably pine and in very good shape. The entire house with the exception of the roof is original.
3, No felt. Full 2"x4" studs
4. Roof overhangs wide, at least 30 inches.
5. Two story house.
6. Fully gutting, saving all the windows which have been covered with storms, replumbing, rewiring and while the roof is in good shape, will replace so it can be properly super insulated. Crawlspace becoming insulated/conditioned. Attic non-vented.
7. Looking for good advice about new Low-e energy efficient storms; do not want wooden ones; we're getting too old to handle these....
Thank you for your advice; I've read pretty well everything on the subject at GBA but still don't know what is best. It is the rainscreen aspect that most confounds me. Solution must be cost efficient; contractor doing the work, not us, the homeowner whose time is meaningless.
Sacie,
If your walls have sheathing, the usual approach is to fill the stud bays with dense-packed cellulose insulation. While adding insulation in this way may (slightly) reduce the longevity of your exterior paint job, the benefits of the insulation outweigh the drawbacks.
If your walls have no sheathing, you can adopt one of the approaches described in this article: Insulating Walls in an Old House With No Sheathing.
Your 2x4 walls aren't deep enough to provide room for much insulation. If you want your walls to have a higher R-value, you can take the "Mooney Wall" approach (thickening the walls by adding horizontal 2x4s on the interior, 24 inches on center), or you can install interior rigid foam.
For more information on this last option, see Walls With Interior Rigid Foam.
Appreciate your response. So if the walls have sheathing I do not need to worry about installing a rain screen? Or is this the point of your suggesting: :While adding insulation in this way may (slightly) reduce the longevity of your exterior paint job, the benefits of the insulation outweigh the drawbacks."
Sacie,
If you live in an older house, you probably have to accept the fact that it isn't built according to modern standards. How much you are willing to invest to make an older house perform better depends on your goals and your budget.
Is a rainscreen gap a good idea? Of course.
How do you retrofit a rainscreen gap on an older building? You remove the existing siding; then you install a new WRB, new flashing, and new furring strips or a three-dimensional plastic mesh product; and then you either reinstall the siding that you carefully removed, or you install new siding.
Can you do that? Sure. Just sign the check after your builder completes the work. It's up to you.
Many people with older houses live without a rainscreen gap.
Useful and most practical advice Martin. A good reality check is what I need. I've already abandoned the idea of taking off the old siding to re-do this house the right way simply because it is too expensive. So now I will abandon the idea it should have a rainscreen. I've read of the various products available to put in a small gap between the studs and the insulation, wondering if these were worth the effort (contractor time spent). Thank you for your advice/