Hitchcock Center for the Environment
Living Building Challenge Education Center
Walls and Roof
The envelope design is based on continuity of the insulation layer and air barrier from footing to eave to ridge to eave to footing. Great effort was made to eliminate thermal bridging. For instance, all roof overhangs (used to harvest rainwater) are independently framed outboard of the insulation layer and air barrier. The actual R-value is not remarkable - R39 - but the designers believe continuity makes up for that. For instance, our recent blower door test shows an extremely tight building meeting Passive House standards.
Subslab assembly
4-inches of expanded polystyrene, continuous under slab, and around foundation wall
Subslab R-value
20.0
Slab edge assembly
Slab edge is isolated from grade our out door air by 4 inches of expanded polystyrene insulation.
Slab edge R-value
20.0
Foundation wall assembly
Conventional poured in place concrete foundation wall wrapped with 4 inches of expanded polystyrene insulation.
Foundation wall R-value
20.0
Above grade wall assembly
siding over plywood sheathing, over 6 inches polyisocyanurate insulation (2 layers of 3 inch, joints staggered), over air and vapor barrier, over 3/8 inch plywood sheathing, over 1.25 inches tongue and groove sheathing
Above grade wall R-value
39.0
Flat attic assembly
Not applicable
Flat attic R-value
0.0
Cathedral ceiling assembly
roofing over plywood sheathing, over 6 inches polyisocyanurate insulation (2 layers of 3 inch, joints staggered), over air and vapor barrier, over 3/8 inch plywood sheathing, over 1.25 inches tongue and groove sheathing
Cathedral ceiling R-value
39.0
Roof Assembly
See cathedral ceiling assembly.
Windows and Doors
Window Assembly:
Alpen 725 Series WIndows
Door Assembly:
Hollow metal door with polyurethane core. Ceco Door, Assa Abloy 1-3/4" Trio-E Door.
Average window U-factor
0.18
Solar Heat Gain Coefficient
0.41
Visible Light Transmittance
0.52
Door U-Factor
0.36
Door Area
273 sq ft
Mechanical Systems
Space cooling - Manufacturer & Model
Mitsubishi R2 Hyper Heat VRF System
Space cooling - capacity
70 kW
Space heating - Manufacturer & Model
Mitsubishi R2 Hyper Heat VRF System
Space heating - capacity
79 kW
Domestic hot water - Manufacturer & Model
EEmax EX1608TC & EX55SLN4
Domestic hot water - capacity
4 gal
Domestic hot water - efficiency
100 kW
Ventilation - Manufacturer & Model
(2) Renewaire HE2XINH
Lighting Manufacturer and Model
Lighting Efficiency
Envelope
Air Changes per hour, ACH50
0.65 ACH50
Air Changes per hour, CFM50
993.00
Walls and Roof
The envelope design is based on continuity of the insulation layer and air barrier from footing to eave to ridge to eave to footing. Great effort was made to eliminate thermal bridging. For instance, all roof overhangs (used to harvest rainwater) are independently framed outboard of the insulation layer and air barrier. The actual R-value is not remarkable - R39 - but the designers believe continuity makes up for that. For instance, our recent blower door test shows an extremely tight building meeting Passive House standards.
| Subslab assembly |
4-inches of expanded polystyrene, continuous under slab, and around foundation wall |
|---|---|
| Subslab R-value | 20.0 |
| Slab edge assembly |
Slab edge is isolated from grade our out door air by 4 inches of expanded polystyrene insulation. |
| Slab edge R-value | 20.0 |
| Foundation wall assembly |
Conventional poured in place concrete foundation wall wrapped with 4 inches of expanded polystyrene insulation. |
| Foundation wall R-value | 20.0 |
| Above grade wall assembly |
siding over plywood sheathing, over 6 inches polyisocyanurate insulation (2 layers of 3 inch, joints staggered), over air and vapor barrier, over 3/8 inch plywood sheathing, over 1.25 inches tongue and groove sheathing |
| Above grade wall R-value | 39.0 |
| Flat attic assembly |
Not applicable |
| Flat attic R-value | 0.0 |
| Cathedral ceiling assembly |
roofing over plywood sheathing, over 6 inches polyisocyanurate insulation (2 layers of 3 inch, joints staggered), over air and vapor barrier, over 3/8 inch plywood sheathing, over 1.25 inches tongue and groove sheathing |
| Cathedral ceiling R-value | 39.0 |
| Roof Assembly |
See cathedral ceiling assembly. |
Windows and Doors
Window Assembly:
Alpen 725 Series WIndows
Door Assembly:
Hollow metal door with polyurethane core. Ceco Door, Assa Abloy 1-3/4" Trio-E Door.
| Average window U-factor | 0.18 |
|---|---|
| Solar Heat Gain Coefficient | 0.41 |
| Visible Light Transmittance | 0.52 |
| Door U-Factor | 0.36 |
| Door Area | 273 sq ft |
Mechanical Systems
| Space cooling - Manufacturer & Model | Mitsubishi R2 Hyper Heat VRF System |
|---|---|
| Space cooling - capacity | 70 kW |
| Space heating - Manufacturer & Model | Mitsubishi R2 Hyper Heat VRF System |
| Space heating - capacity | 79 kW |
| Domestic hot water - Manufacturer & Model | EEmax EX1608TC & EX55SLN4 |
| Domestic hot water - capacity | 4 gal |
| Domestic hot water - efficiency | 100 kW |
| Ventilation - Manufacturer & Model | (2) Renewaire HE2XINH |
| Lighting Manufacturer and Model | |
| Lighting Efficiency |
Envelope
| Air Changes per hour, ACH50 | 0.65 ACH50 |
|---|---|
| Air Changes per hour, CFM50 | 993.00 |