Basement Insulation Upgrade for Post-War Bungalow

My brother is currently adding insulation (2" EPS foam) of to the basement walls of his 1 1/2-story post-war bungalow. I was curious to see the effectiveness of this common approach versus building an R60 wall inside the basement, similar to Yukon Housing Corp.'s "SuperGreen" method.

The house is a well-cared for 1 1/2 story bungalow, very common to Whitehorse, especially in Riverdale. The house has some new windows, modest air sealing, and an un-insulated concrete basement with concrete floor. To estimate the energy savings of the two upgrade options, I built a basic model of this house in HOT2000.

Then, ran the two basement insulation scenarios:

1. 2" Foam - 2" EPS foam, taped seams, 1x4 strapping & drywall - R10
2. SuperGreen wall - 2x4 inner stud wall on 1x4 top & bottom plates creating a 16" cavity filled with cellulose. Vapour barrier and drywall - R60

Energy Saving Results:

Basement Insulation Upgrade:	Base Case	2" Foam	SuperGreen
R-Value of Basement	~ R3.5	R10	R60
Total Building Heat Loss (MJ)	116.4	106.6	103.3
Basement Heat Loss (MJ)	34	20.9	24.2
% of Heat Loss through Basement	29%	22.7%	20.3%
Annual Oil Use (L)	2766 L	2452 L	2346 L
Annual Cost Savings @ $1.00/L	-	$314.00	$ 420.00
Annual Cost Savings @ $1.50/L	-	$471.00	$ 630.00

Note: This does not include re-insulation of the rim joist, which would likely be foamed, resulting in reduced overall air-leakage. I assume this would be common to both scenarios, so didn't model rim joist re-insulation upgrade.

Costs:

Assuming the home-owner supplies the labour for both upgrades, material costs are as follows. Costs common to both options (e.g. drywall) are not shown.

Dimensions are:
W: 28', L: 24', H: 7.5', Perimeter: 104' , Wall Area: 780 sq. ft.

Option 1 Material Costs: 2" Foam

Item	#	Unit	Unit Cost	Item Total
2" Foam Board	54	2x8 boards	$ 32.49	$ 1,754
Foam-Concrete Glue	8	tubes	$ 6.00	$ 48
Hilti gun rental	2	days	$ 30.00	$ 60
Hilti nails	3	boxes	$ 60.00	$ 180
Tuck Tape	2	rolls	$ 14.00	$ 28
Acoustical sealant	2	tubes	$ 3.00	$ 6
1x4 16' strapping	33	ea.	$ 5.27	$ 174
Total Material Costs				$ 2,250

Option 2 Material Costs: SuperGreen

Item	#	Unit	Unit Cost	Item Total
Top & bottom plates	13	1x4 16' stapping	$ 5.27	$ 68
Studs	52	2x4 8'	$ 3.77	$ 196
Accustical sealant	4	tubes	$ 6.00	$ 24
Hilti gun rental	1	days	$ 30.00	$ 30
Hilti nails	1	boxes	$ 60.00	$ 60
Tuck Tape	1	rolls	$ 14.00	$ 14
Vapour Barrier	1.5	100' roll	$ 80.99	$ 121
Cellulose Insulation	70	bags	$ 17.97	$1,258
Total Material Costs				$1,772

Summary
If you can "afford" to loose 16" around the perimeter of your basement, then insulating with the SuperGreen method is the way to go:

Upgrade Option:	2" Foam	SuperGreen	Relative Savings
Material Cost	$ 2,250	$ 1,772	$ 478
Oil Savings (L)	314	420	106
Cost Savings @ $1.00/L	$ 314	$ 420	$ 106
Cost Savings @ $1.50/L	$ 471	$ 630	$ 159
Simple Payback @ $1.00/L (years)	7	4	3
Simple Payback @ $1.50/L (years)	5	3	2
Return on Investment @ $1.00/L	14%	24%	10%
Return on Investment @ $1.50/L	21%	36%	15%