Partial basement insulation
rachelfl
| Posted in General Questions on
Hi There,
We are in zone 3 and planning on insulating our basement with rigid foam and putting the old 70s paneling back over top. The article mentioned code requires drywall, does it just need to be covered or does it need to be drywall?
Also, does it make sense to insulate only half of the basement? We are not planning on insulating the storage/mechanical/laundry half. Would only insulating the one half still be worth it for warmth and energy savings?
Thanks!
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Replies
HI Rachel -
not sure what you mean by "the article?"
This section of the building code applies to foam plastic in basements:
R316.4 Thermal barrier.
Unless otherwise allowed in Section R316.5, foam plastic shall be separated from the
interior of a building by an approved thermal barrier of not less than 1/2-inch (12.7 mm)
gypsum wallboard, 23/32-inch (18.2 mm) wood structural panel or a material that is tested
in accordance with and meets the acceptance criteria of both the Temperature
Transmission Fire Test and the Integrity Fire Test of NFPA 275.
So, yes, y0u need 1/2-inch gypsum wallboard or equivalent fire/smoke protection over the foam plastic insulation.
In terms of is it worth insulating part of your basement? Yes, for insulation. Air tightness is a different story and requires a more comprehensive approach to get full effect.
Peter
I would insulate and air seal the area you’re renovating. I’d also air seal the part of the basement that you are not insulating. The air sealing will help the efficiency of your entire house, and you always have the option to add insulation to the storage/mechical/laundry half in the future if you want to. Partial insulation is better than no insulation, and I look at projects like these as phased upgrades where you complete a large project one small piece at a time. You make a little improvement with every upgrade you install.
Bill