Energy efficiency upgrades during residing.
Hello GBA community. Newer to the website and newer homeowner, but have been studying and reading about building science. I live in Zone 5, have a stick frame house built in 1995 (1300 sf single family, one level). It is nearing time to replace my siding (roofing too) and I want to have a plan for some needed efficiency upgrades. I am trying to keep it simple and cost effective. Want to make some improvements, but this is not my forever home. I’d like to hash out my plan and ask for some critiques. Really appreciate your feedback and insight.
I plan to remove some sheathing and see how well the stud bays are insulated (assume there is fiberglass batts in stud cavities). From the foundation up, I plan to:
1. Seal the sill plate with tape or caulking if not done.
2. If poorly filled stud cavities, plan to install Roxul comfortbatt insulation (R-23). I assume I have 2×6 exterior wall that are 16″ o.c.).
3. For air/water resistive barrier, I plan to either install Zip sheathing (taping v. liquid applied joint sealing) v. a liquid applied membrane (Proseco?) to the existing sheathing.
4. For exterior insulation, I plan to install Roxul Comfortboard 2″ thick (R-8), furring strips, and a siding that is compatible with that setup.
5. New triple pane energy efficient windows. Don’t want to break the bank here. Suggestions? Considering Alpen, Inline, Jeld Wen.
Plan to do the work myself. Will be tackling the crawlspace and attic shortly after. Or, should I start on one of those sides first? Am I missing anything while I have an opportunity to open up the walls?
Thanks very much for sharing your experience and expertise.
Ryan
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Replies
Ryan,
Consider installing reclaimed rigid foam on top of your roof sheathing. (See https://www.greenbuildingadvisor.com/articles/dept/musings/how-install-rigid-foam-top-roof-sheathing.) Reclaimed foam is typically one-half to one-third the cost of new material.
Do you absolutely have to replace the siding? If this is not your forever home, it may be hard to justify the cost purely on the basis of energy saving. If the siding and sheathing are shot, you could follow a strategy that is similar to the roof or use a combination of rigid foam and air permeable insulation. (https://www.greenbuildingadvisor.com/articles/dept/musings/combining-exterior-rigid-foam-fluffy-insulation) If you decide to use a combination of insulation types, cellulose is often the more affordable material.
Zip has a nice system. But regular OSB is worth considering if your plans also include installing rigid foam.
Ryan,
I agree with Steve that your wall improvements may cost more than can be justified by the energy savings. That said, you'll be preparing the house for the future -- whoever gets to live in it.
The best way to seal Zip system sheathing is with Zip system tape.