Walls and Roof

The 100+ year old framing was strong enough on the walls but not the roof, so we replaced the roof with thick framing for superinsulation and added 4" more insulation to the exterior of all the walls and roof. The siding needed replacing anyway, making an exterior approach easy. We were not up to the task of excavating around the foundation, so we had to move inside for the basement insulation.

Subslab assembly

Given the existing slab, we insulated above the slab. Dimple mat to allow movement of any water, taped. 2" rigid foam (XPS) insulation, taped. Click-together laminate flooring.

Subslab R-value 10.0
Slab edge assembly


Foundation wall assembly

We used foil-faced polyiso on the walls to provide a vapor barrier as well as air sealing and insulation. Two layers offset provided backup.
There were masonry nails in the brick foundation, and rather than risk destroying the brick (with hours of hard work) we decided to use thicker insulation on the first layer.
2" + 1" for a total of 3" foil-faced polyiso

Foundation wall R-value 20.0
Above grade wall assembly

The house is balloon framed with actual 2"x4" lumber. Our favorite insulation, dense packed cellulose, was not enough to superinsulate. We used it in the existing framing, and then added 2, 2" foil-faced polyiso layers staggered on the exterior. Furring strips held the siding away for airflow.

Above grade wall R-value 41.0
Flat attic assembly

The third floor is tucked up under the roof, with only a short kneewall above the floor deck. A small amount of flat ceiling has a minimum of 24" of loose cellulose, but otherwise the assembly is cathedral.

Cathedral ceiling assembly

The existing roof was very bowed, in one case slumping 4" just from one end of the dormer to the other. It was not thick enough for superinsulation either, and sistering deeper framing was not a preferred approach by our builders. So we replaced the framing with 2x10s, filled with dense-packed cellulose, and added 2 layers of 2" foil-faced polyiso on top.

Cathedral ceiling R-value 60.0
Roof Assembly

see above

Roof R-value 60.0

Windows and Doors

Window Assembly:

vinyl, Paradigm, mostly double-hung, a few casement, two awning and 3 fixed in basement, all triple glazed, low-e (surfaces 2 and 5) with argon
8321 Premium Double Hung foamed frame

Door Assembly:

Thermatru Smooth Star

Average window U-factor 0.20
Solar Heat Gain Coefficient 0.25
Visible Light Transmittance 0.42
Door U-Factor 0.20
Door Area 100 sq ft

Mechanical Systems

Space cooling - Manufacturer & Model same
Space cooling - capacity 9 kW
Space heating - Manufacturer & Model Daikin (1) 4mxs32gvju 17.2 seer, (3) Daikin ctxs09hvju wall units
Space heating - capacity 9 kW
Domestic hot water - Manufacturer & Model GE Geospring GEH50DEEDSR
Domestic hot water - capacity 50 gal
Domestic hot water - efficiency 2 kW
Ventilation - Manufacturer & Model Venmar Kubix 44112
Lighting Manufacturer and Model
Lighting Efficiency


Air Changes per hour, ACH50 0.65 ACH50
Air Changes per hour, CFM50 476.00