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Detailer

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Build a wall, roof or floor the way it's actually made — layer by layer, exterior to interior finish — and let the drawing carry the data that guides iteration. The hatched section (drawn flat for roofs and floors) redraws live over aligned temperature and vapor-pressure charts: a dew-point (Glaser) pass names the plane where winter condensation would land, effective R/U uses the kind-correct ASHRAE films (heat flowing up, down and sideways differ) and includes what the studs really cost, and weight, installed cost and embodied carbon — pinned to the platform's shared ICE factors — read out beside them. Thirteen presets each teach a lesson (vented attic vs compact roof, the sweating slab); a thermal-bridge gallery covers what a 1-D stack can't see. Send the solved assembly to Assayer and the massing's energy balance and wall/roof carbon read YOUR construction instead of the fixed stand-in. Client-side.

Walls
Roofs
Floors

The default American wall: batts between studs. Watch the framing shave the nominal R, and the OSB run cold in winter.

°F
°F
%RH
%RH

Run the dew-point check at a cold-month MEAN, not just the design low — steady-state analysis at the extreme overstates a wall that can store and dry.

Kind

Exterior layer first (left in the drawing).

1
20.02″
3
4
50.02″
6
Section · temperature · vapor
EXTINT1234566.79″TEMPERATURE °F10°70°dew 41°VAPOR PRESSURE kPasaturationvapor p (dashed)
Plan cut (4′ of wall)
@16along the wall
Thermal
R nominal (as the labels add)R-22.4
R between framingR-22.4
R at the studsR-8.9
R effective (whole assembly)R-16.2
U effective0.062Btu/h·sf·°F
Lost to framing27 %
Heat flow · interior filmhorizontal · R-0.68
IECC CZ5 wood wall · U ≤ 0.045 Passive House ballpark · U ≤ 0.022
#LayerinRperm
1Fiber-cement siding0.310.2cl III
2Housewrap WRB0.020open
3OSB sheathing0.440.5cl III
4Fiberglass battwood @165.520.4open
5Kraft facing (on batt)0.020cl II
6Gypsum board0.50.5open

This solver is 1-D — it can't see the junctions where assemblies meet. Thermal bridges — the gallery →

Moisture — steady-state dew-point check
Dew point (indoor air)41 °F

Condensation predicted at OSB sheathing · Fiberglass batt12 °F with vapor pressure 0.48 kPa over a 0.27 kPa saturation limit.

Glaser method: steady state, no rain wetting, no storage, no air leakage — a screening tool that finds the risky plane, not a hygrothermal simulation.

Matter
Total thickness6.79″
Weight5.9lb/sf
Installed cost$18.25/sf
Embodied carbon (A1–A3)2kgCO₂e/sf

Carbon factors: 3 of 6 layers pinned to the platform's shared ICE v4.0 table (the same numbers Footprinter and Assayer use). ≈ Wider band — study values, no repo factor: Fiber-cement siding, Housewrap WRB, Kraft facing (on batt).

Study values for comparing iterations — handbook R and perm ratings, rough 2025 US installed costs. Not for bidding, compliance, or an LCA.

Test in Assayer

Assayer’s energy balance and embodied-carbon read assume one fixed construction. Sync → Test the wall in Assayer (top of the page) sends the solved wall — effective U 0.062 (0.35 W/m²K) with framing + films, carbon 2 kgCO₂e/sf — so the massing is judged in the assembly you actually drew. Send the wall, switch Kind, send the roof and floor — the slots travel together. Glazing and the slab’s per-volume carbon keep Assayer’s fixed build-ups.

Iterations — the compare bench

Save the wall as you iterate — each row keeps its own layers and conditions, and the table lets the versions argue: R against thickness against cost against carbon.

Load a wall file

Reads the file Export → Wall JSON writes. To keep a wall inside the site instead, use Save — same layers, no download.