I'm trying to decide where to invest my dollars to save money on the "whole picture" of my home's energy use.
It's a 1974 colonial in Southern New Hampshire, USDA Zone 4. 3000 square feet of conditioned space. Propane furnace in winter, central air conditioning used sparingly in the summer. At current energy prices, yearly total spending is about
$1600 electricity
$900 water heating
$1900 space heating
I estimate I'm using 60 MBTU per year for space heating. I think it is reasonably well insulated, new windows etc. But I don't believe any effort was made for air-sealing the attic, basement, top plates, plus all the little passthroughs for bathroom vents, HVAC ducts, etc.
So I'm trying to evaluate two projects:
My payback estimate on the stove is 4-5 years. Has anyone gone down the road of spray foam in existing construction, to estimate the payback period? And how much I should expect my yearly MBTU to be reduced? The spray foam is appealing because it helps during heating and cooling season. But I don't know if the marginal efficiency increase is justified.
It's a 1974 colonial in Southern New Hampshire, USDA Zone 4. 3000 square feet of conditioned space. Propane furnace in winter, central air conditioning used sparingly in the summer. At current energy prices, yearly total spending is about
$1600 electricity
$900 water heating
$1900 space heating
I estimate I'm using 60 MBTU per year for space heating. I think it is reasonably well insulated, new windows etc. But I don't believe any effort was made for air-sealing the attic, basement, top plates, plus all the little passthroughs for bathroom vents, HVAC ducts, etc.
So I'm trying to evaluate two projects:
- Removing all the fiberglass and cellulose attic insulation and having it sprayed with closed-cell spray foam. There are two rooflines, with 1400 sq ft total attic space. My ballpark estimate is $8,000 for 6" R-42 equivalent.
- installing a Blaze King King in the main living floor, plus stainless liner and some non-trivial chimney modification. I'm estimating $6,000.
My payback estimate on the stove is 4-5 years. Has anyone gone down the road of spray foam in existing construction, to estimate the payback period? And how much I should expect my yearly MBTU to be reduced? The spray foam is appealing because it helps during heating and cooling season. But I don't know if the marginal efficiency increase is justified.