Sterling’s Loft — BUILD PLAN (FINAL FRAME, 2026-06-11 — TORSION-BOX DECK (V2 frame + 3.0” stressed-skin panel + single-2x6 beam, bed-bolted; no hangers; 2026-06-14))

Generated from config/dimensions.json + the live board geometry by planning/build_plan.py. Verified by verify.py (all 12 dimensional gates PASS, incl. the Govee-downlight fit). The loft + railing cut lists are derived from the 3D boards — the drawings, cut list, and model cannot drift apart.

Design: STAINED wood loft, deck 55” · queen platform 4” (32” top / 38” lower headroom over the sleeping area) · loft 56.5” x 104.25” · DECK = a 3.0” TORSION BOX (stressed-skin panel): 3/4” 1x6 top boards + 1.5” 2x2 webs + 3/4” 1x6 T&G bottom skin, dropped onto a perimeter ledge, top flush at the deck. The bottom skin sits at 52” and houses 2 recessed GOVEE 4” DOWNLIGHTS over the queen. Two skins held 3” apart = ~6x a 1” slat’s strength / ~21x its stiffness, sized as a BUNK (holds well past 500 lb). · flush SINGLE-2x6 beam, head BED-BOLTED to the corner post (furniture joint, no hanger) · NO knee wall — a floor-to-rail 4x4 GRAB POST at the 24” opening, tied to the drawer cabinet · foot rim lagged to the front wall · crib-style railing panels 22” (flat 2x4 rail over the post tops) · B-2 ladder on a French cleat · 10” hollow bookshelf headboard. Both mattresses spring.

1. BUY LIST — dimensional lumber

ORDER quantity = boards the cuts consume (kerf-aware nesting — matches the cut diagram) + 1 spare 2x6 and 1 spare 2x4 (insurance, confirmed 2026-06-13). A miscut/split comes out of the spares, not a mid-build store run.

STAINED finish: hand-pick clear/select boards at the store for the VISIBLE faces — the TOP-SKIN deck boards (most-seen surface), the beam, flat top rails, grab + corner posts, ladder. Same dimensions, just prettier pieces; knots/dents hide on the hidden side.

2. BUY LIST — sheet goods & panelling

3. BUY LIST — hardware, lighting & finish

Trim & moulding (finish)

4. CUT LIST (dimensional lumber, by component — loft/railing rows derived from the 3D boards)

See output/cut_diagram.* for the visual cut sheets (pieces nested on stock boards). Plywood cuts are derived per cabinet at build time; sheet counts in section 2.

5. ASSEMBLY — solo build, stick-built in place

Build-order answer: do NOT pre-assemble the loft frame and lift it — and there is no mid-air balancing either. The ledger, posts, and front-wall pocket go up first as fixed supports; every later member rests on hardware while you screw it. The only heavy-ish solo lift is the single 2x6 beam (~15 lb), one end at a time onto supports that already exist. The ONE genuine two-person step is dropping the ~100 lb prefab torsion box onto the ledge — line up a helper for that (or split it on a web seam).

PREP (indoors / the shop)

1. Find + mark every stud on the ledger wall AND the front wall (the foot rim lags there + the beam pocket). Mark the frame-top/deck line at 55” and the box-bottom line at 52”; check level against the ceiling.
2. Build the 4-drawer cabinet carcass — POCKET-SCREW + glue the carcass; drawer boxes BUTT-jointed (glue + brads/pocket screws) on full-extension slides; no dados/router. Notch the bottom-right ~3.25 x 3 x 14” around the heater.
3. Cut the 2 WALL posts to deck height and NOTCH each 1.5 x 5.5” at the top wall-side corner — the full-length 2x6 ledger passes through the notch and bears on the shoulder. (Corner + grab posts stay full to the rail underside, no notch.)
4. Cut the SINGLE 2x6 BEAM to length. Drill its bed-bolt joinery in the shop: in the head end, the bolt clearance hole + the cross-dowel hole; counterbore the matching bolt holes in the corner post (a bed-bolt jig keeps them aligned). Same bed-bolt prep at the head-rim segment ends + their posts.
5. PREFAB the two railing PANELS flat (crib style): 2x2 bottom strip + 2x2 spindles (~3.2” gaps) + the flat 2x4 top rail, screwed together face-down.
6. BUILD THE TORSION BOX flat on the floor (the key prefab): lay the 3/4” 1x6 T&G bottom skin down; glue + screw the 1.5” 2x2 WEBS to it (2 lengthwise edges + rungs every ~8”); DRILL + CHISEL (or Dremel) wire channels in the webs + cut the 2 x 4” GOVEE DOWNLIGHT cutouts in the T&G, CENTERED in clear web bays (on the bed centerline, evenly spread along the box — keep them out of the webs; the bottom skin is the structural flange, so no more holes than needed); glue + screw the 3/4” 1x6 TOP BOARDS down across the webs. GLUE IS STRUCTURAL — the bond makes the two skins act as one 3” section. Clamp until set.

DAY 1 — walls + skeleton

1. Cut away the 1/2” drywall strip on the ledger line. Lag the 2x6 ledger to bare studs — one 1/2” x 4” lag per stud, pre-drilled, level.
2. Same on the FRONT wall: drywall strip out, lag the foot rim to the studs at the frame line (the 2nd ledger).
3. Set the 4 posts on post bases — 2 wall posts, the 4x4 CORNER post, and the OPENING GRAB POST at the landing edge (NO knee wall — V2 frame). The 2 wall posts seat with their NOTCHED tops over the ledger (notch cut in PREP) — the ledger runs through and bears on the shoulder. Post inner faces flush with the head-rim line; carriage-bolt the grab post’s back through the drawer-cabinet climb edge (2 bolts).
4. Set the beam: foot end pocket-screwed to the foot rim (>=1.5” bearing on the front-wall framing), head end BED-BOLTED to the corner post — drop the 2 cross-dowels in the beam, run the two 3/8” bed bolts through the post and snug them. One end at a time, solo-safe; plug the counterbores at finish. (Furniture joint — concealed + demountable, no hanger.)

DAY 2 — drop the deck

1. Set the two HEAD-RIM segments on the post line (wall post -> grab post, grab post -> corner post) and BED-BOLT each end into the post face (cross-dowel + 3/8” bolt, counterbore plugged).
2. Screw the perimeter LEDGE (2x2) around the inside of the frame — top edge at the box-bottom line (52”), level all the way round.
3. LIFT THE PREFAB TORSION BOX in and drop it onto the ledge — top boards finish FLUSH with the frame at the deck. Screw the box down into the ledge + the beam/rims. Build the box ~1/4” UNDERSIZED in each direction (vs the frame inner opening) so it actually drops onto the ledge with clearance — a zero-clearance box won’t seat. This is the ONE genuine TWO-PERSON lift (~100 lb, ~4.5x6 ft) — get a helper, or split it on a web seam; don’t force it solo.
4. Set the drawer cabinet; add the 2 landing edge rails + the 3/4” ply landing, flush with the deck.

DAY 3 — railing + access

1. Stand the two PREFAB railing PANELS: bottom strip screws into the beam / head-rim top, rail ends lag into the posts; the flat 2x4 top rails run continuously OVER the post tops (room-side rail over the corner post, head rail over the grab post).
2. Build the removable ladder (~59°, 2x4 stiles): DADO each stile inner face 3/4” deep x 1.5” tall at every tread line (even 7.9” risers), GLUE the 2x8 treads into the dadoes and drive 2 screws from OUTSIDE each stile into the tread end; plumb/seat-cut the foot so it lands flush under the loft edge (no projecting toe). Add the FRENCH-CLEAT pair (45° bevel — one on the climb-edge landing rail, one on the ladder back) + a drop-pin latch.
3. Headboard bookshelf carcass — POCKET-SCREW + glue the sides/shelves/dividers, then GLUE + BRAD-NAIL the 1/8” back on to square it (no dados/router); nooks centered on the queen; fasten to wall studs + posts. The bedside niche has a SOLID panel at its bottom for the 3-gang switch box (faceplate left + bottom flush with the shelf grid, ~22-26.5” up).

DAY 4 — queen + finish

1. Queen platform: 2x4-on-edge frame (60x80 outer, end/cross rails 57”) + 3 cross members + LENGTHWISE slats. SKIRT the 2 visible sides with a TOE-KICK reveal (skirt set back ~1.5” near the floor) and run the UNDER-BED LED strip in it (the ‘floating bed’ floor wash). Set the new queen mattress.
2. Set the 2 GOVEE DOWNLIGHTS into the box bottom-skin cutouts (1.4” body in the ~2.25” cavity; trim flush, dimmable over HA) + panel-mount USB in the headboard. Run the SHELF LED strips in their channels (front underside lip of each opening + the niche), wiring hidden behind the back panel to the nightstand outlet. Set the smart-switch boxes: the BEDSIDE 3-GANG on the solid panel at the niche bottom (left + bottom flush with the shelf grid — shelf LEDs · downlights · under-bed glow); TOP BUNK on the long wall beside the loft pillow (~12” above the deck).
3. Sand visible faces to 150-180, stainable filler, STAIN + 2-3 coats water-based poly (top boards, caps, treads get 3). Move the double mattress up.

6. JOINERY DETAILS

• TORSION BOX (the deck): a stressed-skin panel — 3/4” 1x6 top boards + 1.5” 2x2 webs + 3/4” 1x6 T&G bottom = 3.0”. Build it FLAT and prefab: glue + screw BOTH skins to the webs (top boards across the webs, T&G under them). The glue is structural — it’s what makes the two skins act as one deep section; skip it and you have two loose panels.
• Webs (‘slats in the middle’): 2 lengthwise 2x2 edges + widthwise 2x2 rungs every ~8”. They hold the skins 1.5” apart (the downlight cavity) and carry the shear between them. DRILL + CHISEL wire channels + cut the 2 x 4” downlight holes (centered in clear web bays) BEFORE closing the top.
• Perimeter ledge: a 2x2 run around the inside of the 2x6 frame, top edge at 52”; the prefab box drops onto it and screws down into the ledge + beam/rims. Top boards finish flush at the deck.
• Beam head end — BED-BOLTED (furniture joint, no hanger): the SINGLE 2x6 beam butts the full corner post and is held by two 3/8” bed bolts (vertically spaced) into cross-dowels a few inches back in the beam — the canonical bed-rail-to-post joint. Concealed (counterbore + wood plug) and demountable. The head reaction (~125 lb realistic, ~295 lb at 40 psf) is far inside a bed bolt’s shear capacity; the box continuously screwed to the beam top braces it. The 4x4 stays full (no notch). See sheet 5, panel D. (Built like a bed, not a deck — STRUCTURAL.md §0.)
• Foot rim = 2nd ledger: drywall strip out, 1/2” lag per front-wall stud — the frame’s third wall capture.
• Grab post (no knee wall): post line FLUSH with the head-rim inner face; the two head-rim segments BED-BOLT into its x-faces (no hangers), and its back carriage-bolts the drawer-cabinet climb edge (2 bolts, nuts inside).
• Wall posts (NOTCHED): the 2 wall posts run floor->deck and are notched 1.5x5.5” at the top wall-side corner so the full-length 2x6 ledger passes THROUGH and bears on the notch shoulder; the corner + grab posts stay full to the rail underside. Cut the notch in the shop (PREP).
• Railing panels: prefab flat (2x2 strip + spindles + flat 2x4 rail); strip screws into the beam/rim top, rail ends lag into the posts, rails run OVER the post tops.
• French cleat: one 45-deg bevel rip down a 2x6 makes both halves; bevel up-toward-wall on the landing rail, down-toward-wall on the ladder.

7. TOOLS & BITS (beyond drills/sanders/saws)

• Stud finder + 4-ft level + speed square (ledger line is the whole build’s datum).
• 1/2” clearance bit + 5/16” pilot bit + 3/4” socket for the ledger lags (or just a T25 driver if using structural screws).
• 3/8” bit for carriage bolts; countersink; 4” hole saw for the 2 Govee downlight cutouts in the box bottom skin.
• Pocket-hole jig (Kreg) + 2-1/2” coarse screws — headboard, drawer boxes, queen frame.
• Sanding block / chamfer (no router) — ease the flat top rails + grab/corner post edges for kid-safe corners (80→150 grit, or a block plane).
• Kreg pocket-hole jig (casework + queen frame), 18ga brad nailer (backs/trim/panel), 4–6 bar clamps (glue-ups). Circular saw + guide rips the French-cleat bevel (blade at 45). NO router, NO table saw — see the Tools list in SHOPPING_LIST.

8. STRUCTURAL — load path & member check

⚠️ Informal review (not a stamped calc) — full writeup in planning/STRUCTURAL.md. Sized as a BUNK, not a floor (you can’t stand on it at 32” headroom; lying loads, ~2 people). The proven reference is Ryan’s existing sturdy bunk; the box adds a big margin on top.

• Load path: mattress -> TORSION-BOX deck (top boards + webs + bottom skin act as one 3” panel) -> perimeter ledge -> 2x6 frame; beam (single 2x6) -> corner-post BED BOLT (head) + foot-rim/front-wall (foot); ledger + foot-rim lags into the walls.
• Torsion box: two skins held 3” apart = the flanges of a deep section -> ~6x the strength and ~21x the stiffness of a single 1” slat. Distributed: the deck takes well over 1,000 lb at the safe stress; a concentrated load on even a 6” patch is good for ~900 lb safe. Comfortably past the 500 lb (3 small / 2 large adults) target.
• Headroom: box bottom at 52” -> ~38” over the sleeping area (head rises into the open frame cavity to the box bottom). The room-side beam stays at 49.5” over the foot, as always.
• Lateral: ledger wall + front-wall foot rim + the bolted grab/corner posts (grab post tied to the drawer cabinet) + the rigid torsion-box diaphragm — no knee wall, no gussets.
• ⚠️ The real items: the skin-to-web GLUE BONDS (composite action), drywall strips out + lag per stud (both walls), front-wall beam pocket on solid framing.

9. SAFETY / CODE (see planning/code_requirements_ontario.md)

• Guardrail: cap 22” above the deck = 13” above the mattress (verify #8; 5” minimum), gaps 3.2” (< 3.3”, verify #9).
• Egress window stays clear (verify #10): loft/ladder miss the right-side openable slider.
• Smoke + CO alarms on the floor (CO now required every storey).
• VERIFY LOCALLY (Minden Hills, 7 Milne St): permit? building-element vs furniture? ceiling height?

10. STILL TO MEASURE / DECIDE

• Wall stud locations (ledger + French cleat) — field item; also sets the exact lag count.
• Front-wall framing at the beam foot (x~56.5, y~104): stud/blocking — the beam foot pocket-screws to the foot rim here (>=1.5” bearing).
• Faux ceiling + downlights: the torsion-box bottom skin IS the faux ceiling (structural) — cut the 2 x 4” Govee downlight holes in it before closing the box.
• (Heater length 105” and queen mattress 10” are confirmed.)

COST ESTIMATE (approximate, CAD — verify at the store)

Ballpark at Home Depot / Home Hardware, SPF/spruce paint-grade. Not a quote — lumber and sheet prices move; treat as order-of-magnitude. Loft mattress is reused (Ryan’s existing).

All-in (build + queen mattress): ~$2,236 – $3,320 CAD.

Re-run python3 planning/build_plan.py after any change; python3 verify.py must stay green.