We need to develop standard wall sections and roof details.
Wall Construction
Studs are 3½" 2x4 or 5½" 2x6. Typically filled with kraft-faced fiberglass batt insulation (R-13 for 2x4, R-19 for 2x6). A 6-mil polyethylene vapor barrier goes on the inside, covered by gypsum board (½" thick unless between garage and residence, when 5/8" Type-X gyp board is required).
Sheathing on the outside of the studs can be OSB, but plywood is preferable. 7/16" OSB is minimum if wood sheathing is provided. Often, plywood is used so that the sheathing is in plane with the shear walls. CDX plywood sheathing is 15, 19, or 23 32nds of an inch (roughly 1/2", 5/8", or 3/4", actually .438", .563", or .688"). In theory, wood sheathing is optional, but it is almost always used.
Zip System (by Huber), PolyWall. Zip System is sheathing, not foam insulation. It goes against the studs and foam goes outside it. ZIP System R-Sheathing is a 7/16" OSB with a water-resistant face on the exterior and a rigid foam bonded to the interior face. It comes in 15/16" (R-3), 1-7/16" (R-6), 1-15/16" (R-9) and 2-7/16" (R-12) total thickness. PolyWall is flashings for openings, below grade waterproofing and related products. ZIP System comes in green (7/16") or brown (1/2" or 5/8").
Risinger suggests plywood on the first floor, OSB above, perhaps.
House wrap goes outside the sheathing. Tyvek, or similar. Could be 15# building paper, but that's old school. House wrap is an air barrier, but allows moisture vapor to escape. Dupont Weathermate Plus is an alternative that is translucent so you can see the nails.
This video says have the lumber yard rip 1-1/2" wide strips of 3/8" CDX plywood for use as strapping outside ZIP system sheathing. No house wrap, no extra foam. But it gives 3/8" of rain screen behind Hardiplank. Strapping goes wherever a stud is, so the siding is solidly attached.
Any rigid foam goes outside the house wrap. For example, Enerfoil polyiso offers R-6.2 per inch and comes in ½", 5/8", 3/4", 1", 1½", 2", 2½", 3", 3½", and 4" thicknesses. Johns-Manville sells foil-faced rigid polyisocyanurate foam boards. The foil goes on the exterior side. Owens-Corning sells 2"-thick XPS (extruded polystyrene) that is R-5 per inch.
Horizontal siding, such as Hardiplank, can be installed directly on foam board up to 1" thick, but for thicker foam, vertical strapping--like lath, only vertical--is used and the strapping provides a 1/4" to ½" air space between the foam and the siding.
Hardiplank (by James Hardie Building Products) always requires a 1-1/4" minimum overlap, but is available in 4", 5", 6", 6-1/4", 6-3/4", 7", 8", 8-1/4", and 10-3/4" exposures. A 1/4"-thick lath board is run along the bottom edge to angle the first course correctly.
For a raised floor, I think the sheathing extends past the sill plate and covers the rim joist and mud sill as well. Flashing is nailed to the sheathing and runs under the exterior wall layers, then turns down again, creating a flashing "cap" on the exposed concrete footing.
A real brick veneer is the same up to the foam board. The brick is held off from the foam for a 1" air space.
Faux brick or stone is adhesive-applied (that is, "thin set"). You need a "dimple mat" (see Dorken). Matt Risinger uses a dimple mat with synthetic lath (metal lath rusts) pre-attached. His stucco guy then does a scratch coat and a brown coat. Instead of a finish coat for a stucco wall, he uses thin set mortar to adhere thin brick or stone.
In addition to horizontal siding, we could have vertical wood siding (tongue and v-groove, for example), panels, or even cement plaster ("stucco").
Typical Walls
Floor Construction
AdvanTech - Matt Risinger uses 1-1/8" tongue-and-groove subfloors on I-joists (LVL plywood top and bottom on an OSB web). AdvanTech, from Huber, comes in 19/32" (5/8"), 23/32" (3/4"), 7/8", 1", and 1-1/8"
Roof Construction
Roof framing is often 2x4 trusses, even for low-slope "flat" roofs. A 12" high truss allows utilities and insulation.
Ice and water shield goes on first--it's a 36" peel and stick product that goes at the low edge. Synthetic underlayment goes under the whole roof--that is, over the ice and water shield and the rest of the sheathing. IKO Stormtite. Next, install the drip flashing on top of the synthetic underlayment.
Roof Top Insulation by Matt Risinger for his "Monopoly House." He eliminates all overhangs and runs ZIP System sheathing up to the roof. The walls are green ZIP sheathing and the roof is brown 5/8" ZIP sheathing. All edges are taped with black ZIP tape. The air and moisture barrier is continuous from the foundation up to the ridge.
Above the ZIP roof sheathing, he has 2" polyiso (Atlas Roofing) continuous. Above that, he has 2" flat LVL framing @24" to support the overhang, 2" more inches of polyiso between the outriggers. Unvented attic--no eave, gable or ridge vents. This 2" polyiso is specifically for roofs because it has a fiberglass facer for waterproof-ness. So it's framing, then ZIP sheathing, then 2" polyiso, then 2" outriggers with 2" polyiso, then more ZIP sheathing. Note that the first 2" polyiso layer hangs over the wall sheathing to protect the outer layers of the wall section. 4" of polyiso is roughly R-22.8.
The rafter tails on the main house are cantilevered--they run about 2x the overhang up the roof and just stop. (See video @3:24.)
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