Technical notes · 6 Great Circle, Shelter Island
The Juno panel.
Eleven layers, 366 millimeters, made to last. These notes are for anyone who wants to see how the walls of 6 Great Circle are built, what they are made of and how they perform.
Every dimension comes from the drawings of the house. The performance figures are those of the panel system, each set against the building code or a typical wall.
The Juno panel
Eleven layers, 366 millimeters, made to last.
Wall EW02 of the main house: 7,080 mm long, 3,245 mm tall, framed for window M03 and drawn to 2 millimeters. Point at any piece to read its mark.
- Lime plaster on gypsum board13 mmThe room side, finished by hand.
- Inner sheathing, OSB11 mmClosed once the services are in.
- Service cavity, 45 × 45 battens with mineral wool45 mmCables and pipes run here, so nothing pierces the airtight layer.
- Sheathing, OSB/311 mmNailed at 150 mm along every edge.
- Vapor and air barrierfoilLapped 200 mm at every edge and taped, so the air barrier is continuous.
- Frame, C24 spruce 45 × 195 at 600 mm, mineral wool195 mmThe structure and the warmth. R-33.
- Sheathing, OSB/311 mmStainless steel staples every 150 mm along the edges, 300 mm in the field.
- Wind barriermembraneStops the wind, lets moisture out. 200 mm overlaps.
- Ventilation battens 25 × 48 at 600 mm25 mmAir moves behind the boards and keeps the wall dry.
- Nailing battens 34 × 70, six rows34 mmWhat the cladding is fixed to.
- Vertical timber boards, tongue and groove21 mmThe outside of the house.
The build-up
Eleven layers, from the room to the weather.
Read from the inside out. Thicknesses are as drawn; the wall is 366 millimeters in all.
| Layer | Thickness | What it does | |
|---|---|---|---|
| 01 | Lime plaster on gypsum board | 13 mm | The room side, finished by hand. |
| 02 | Inner sheathing, OSB | 11 mm | Closed once the services are in. |
| 03 | Service cavity, 45 × 45 battens with mineral wool | 45 mm | Cables and pipes run here, so nothing pierces the airtight layer. |
| 04 | Sheathing, OSB/3 | 11 mm | Nailed at 150 mm along every edge. |
| 05 | Vapor and air barrier | foil | Lapped 200 mm at every edge and taped, so the air barrier is continuous. |
| 06 | Frame, C24 spruce 45 × 195 at 600 mm, mineral wool | 195 mm | The structure and the warmth. R-33. |
| 07 | Sheathing, OSB/3 | 11 mm | Stainless steel staples every 150 mm along the edges, 300 mm in the field. |
| 08 | Wind barrier | membrane | Stops the wind, lets moisture out. 200 mm overlaps. |
| 09 | Ventilation battens 25 × 48 at 600 mm | 25 mm | Air moves behind the boards and keeps the wall dry. |
| 10 | Nailing battens 34 × 70, six rows | 34 mm | What the cladding is fixed to. |
| 11 | Vertical timber boards, tongue and groove | 21 mm | The outside of the house. |
How it is put together
Drawn to 2 millimeters, fixed at 150.
Frame
C24 spruce. Studs of 45 × 195 mm at 600 mm centers, between a double bottom plate and a top plate, with two rows of noggings.
Openings
Jack studs carry a four-piece header of 45 × 195 mm. Cripples above the header at 370 mm centers.
Sheathing
11 mm OSB/3 on both faces of the frame. Outside, stainless steel staples of 44 × 11 mm at 150 mm along the edges and 300 mm in the field. Inside, 3.3 × 63.5 mm nails at the same spacing.
Air and vapor
A foil vapor and air barrier on the warm side, lapped 200 mm at every edge and taped. A wind barrier outside the sheathing, lapped 200 mm.
Service cavity
45 × 45 mm battens and 45 mm of mineral wool inside the airtight layer. Cables and pipes run here, so nothing pierces the envelope.
Insulation
195 mm of mineral wool between the studs and 45 mm in the service cavity. R-33 for the wall, R-61 for the roof.
Ventilated cladding
25 × 48 mm vertical battens at 600 mm, 34 × 70 mm nailing battens in six rows, then 21 mm vertical tongue and groove boards from a 627 mm plinth line. Air moves behind the boards and keeps the wall dry.
Tolerances
Every element is drawn 2 mm inside its line, so walls meet at a 4 mm joint that closes tight and stays closed.
Performance
Designed for Shelter Island weather. Proven in a laboratory.
Each figure is set against the building code or a typical wall, with what it means for the rooms.
- 0.171W/m²KExterior wall U-value, R-33
About half the heat loss of a code-minimum wall. On a 23 °F night the room side of this wall stays within a degree of the room.
- R-61Roof insulation value
Attic-grade insulation over every room. In August it keeps the sun out the same way.
- 0.80W/m²KWindow U-value, average
Less than half the heat loss of a standard double-glazed window. No cold draft from the glass in January.
- 90minWall fire resistance, tested to EN 1365-1
The gypsum and mineral wool hold a fire back for an hour and a half, proven in a furnace, not on paper.
- STC 54Sound rating of the exterior walls
A normal conversation in the next room is not heard. Rain on the boards is a whisper.
- 60kg/m²Wall weight, about a seventh of masonry
Light walls mean modest foundations and less load on the ground. The strength is in the engineering, not the mass.
- 127mphWind design speed, ASCE 7-16
The coastal design wind speed the walls are engineered for, well above a strong nor'easter.
- ESR-5457ICC-ES evaluation for US building codes
The report a building inspector reads. It confirms the panel system meets the US codes.
Wall EW02 in pieces
45 pieces of spruce, 20 sheets, 37 battens.
The marks are those on the drawings; point at a piece in the model above to find it.
| Mark | Piece | Length | Pieces |
|---|---|---|---|
| Frame, C24 spruce 45 × 195 | |||
| B1 | Horizontal framing, nogging | 288 mm | 2 |
| B2 | Horizontal framing | 473 mm | 2 |
| B3 | Horizontal framing, nogging | 555 mm | 14 |
| B4 | Horizontal framing | 608 mm | 1 |
| B5 | Header over window M03 | 1,939 mm | 4 |
| B6 | Second bottom plate | 4,623 mm | 1 |
| B7 | Bottom plate and top plate | 7,080 mm | 2 |
| B8 | Cripple above the header | 304 mm | 6 |
| B9 | Jack stud | 2,566 mm | 2 |
| B10 | Stud | 3,110 mm | 11 |
| Service cavity battens, 45 × 45 | |||
| A1 | Above the window | 544 mm | 4 |
| A2 | Full height | 3,150 mm | 6 |
| Ventilation battens, 25 × 48 | |||
| C1 | Above the window | 589 mm | 4 |
| C2 | From the plinth line | 2,618 mm | 12 |
| Nailing battens, 34 × 70 | |||
| D1 | Beside the window | 586 mm | 4 |
| D2 | Above the window | 1,945 mm | 1 |
| D3 | To the window | 4,646 mm | 4 |
| D4 | Full length | 7,080 mm | 2 |
Questions
Ask us about the build.
We are glad to walk through the drawings, the test reports and the finished house.
Contact Juno
212 516 3729