Project Cost Estimate

Updated: Oct 22, 2026 (cost tracking and forecast; estimate sections last revised Oct 1, 2026)

Cost tracking

Estimate vs. actual spend over time

The estimate line is the projected total cost of the shed on each date: everything spent so far plus the estimate for what was still left to buy (with the estimate's 5% overage and 8% tax). It steps up when a purchase costs more than its estimate or wasn't in the estimate at all (a tool, a delivery fee), and when the estimate itself was revised. The last step, Oct 22, is the full forecast, which also takes off the pending returns. Hover for the purchases behind each step.

What the money has bought

Where the remaining estimate sits

Why the projection is over the estimate

Estimate $6,512; projection $9,881.26; overrun +$3,369.26 (+51.7%). Section figures are pre-tax.

Underestimated sections

• Cedar trim: the fascia and shadow boards alone cost $574.96 against $406 estimated, 41.6% under. The estimate assumed 2x8x8 boards at $40; the order needed 2x8x12 at $70.98 for one-piece runs. The cedar 1x2s ($24.24) weren't in the estimate.
• Hardware: stainless trim screws, the Simpson connector set and their SD9112 screws cost more than the generic hardware lines. Some of this follows from the roof redesign.
• Wall sheathing: 13 sheets bought against 12 estimated.

Bottom line: about four-fifths of the overrun is spending the estimate never covered (tools, site work, delivery). Genuine estimating misses add up to about $309 (9%), almost all in the cedar trim; the roof redesign added about $261 net.

Full breakdown by cause: Cost Ledger.

Charts are generated from documented figures only. “Where the remaining estimate sits” reads the SUMMARY table below at render time — it holds no copy of the section totals, so it cannot drift from them. Edit a section subtotal and the bar moves with it. The estimate series uses the five revisions that are recorded with a date and a reason; the July 2026 audit adds are folded into the July point because the document was revised in place without preserving intermediates. Spend series is every dated receipt in the Cost Ledger, and sums to its running total exactly. Overage and tax are derived as materials × 1.05 × 1.08 — a model that reproduces every historical total on record ($4,326, $5,489, $5,928, $6,138, $6,432, $6,503, $6,512).

About this estimate

REVISED: Cedar Shingle Siding with Plywood Sheathing

Atlanta, GA (30316) - February 2026 (roof sections revised Oct 1, 2026)

Based on: Jamaica Cottage Shop 10x12 Gable Plans
Modifications:

• Pressure treated lumber instead of hemlock for framing
• Cedar shingles instead of pine board & batten siding
• Cedar trim instead of pine trim
• Plywood wall sheathing with #30 organic felt (bought later from a roofing supply house)

Roof revision Oct 1, 2026: see the banner above.

Excludes: Tools; gravel, 4x6 pad edging, and electrical conduit (already on site)
Includes: 5% overage for mistakes/waste

REVISED July 2026 per Dimensional_Lumber_and_Foundation_Addendum.html: floor joists to 16" o.c., rafters cut two-per-12-footer, plywood seam blocking added (superseded Aug 2026 — now symmetric studs), temporary bracing added, new Site Drainage & Foundation section (pad drain, blocks, termite shield).

SUMMARY

Reconciled Aug 13, 2026. This table now mirrors the detailed sections one row per section, so the summary and line-item views cannot drift apart again. The previous cross-cutting categories (Framing Lumber / Plywood / Housewrap) had done exactly that: they summed to $4,670 against a stated $5,228, omitted the Finishes section entirely, and carried Hardware at $335 against an actual $515. The detailed tables were correct throughout — only these roll-ups were stale.

COMPARISON TO OTHER OPTIONS

The plywood sheathing approach adds ~$250 vs nailers-only but provides:

• Industry-standard, documented installation method
• Better weather protection
• Easier/faster installation (sheets vs. dozens of nailer strips)
• Added structural rigidity (racking resistance)

DETAILED BREAKDOWN

FLOOR FRAME - Pressure Treated

Floor ply corrected to 4 sheets (July 2026 audit F8): the plans' p.7 shopping list says 3, but their own p.21 layout (2 full + 2 half + 2x8 + 2x4 = 120 sq ft) requires 4 — same class of internal contradiction as the metal panel count.

Joists upgraded from 24" to 16" o.c. (10 joists + blocking) to recover the stiffness lost going from full-dimension hemlock to nominal PT. Cut joists 117" (not the plans' 116½") — see addendum.

POSTS & BEAMS - Pressure Treated

WALL FRAMING - Pressure Treated

July 2026 audit adds: +1 2x4x8 (short-piece yield), 1x4x12 spreader, 1x4x8 door header, 11th wall-ply sheet. Seam blocking: flat 2x4s behind wall-plywood edges — posts at 72" o.c. don't back 4x8 sheet edges. Temporary bracing per plans p.25 stays up until roofing is complete. Interior girts (late-July add): structurally optional — the ply box carries the shear — but installed at Phase 3 while bays are open they back the interior liner/pegboard, give shelf nailers everywhere, and stiffen the sheathing field.

ROOF FRAMING — SYP rafters + SYP ridge + Cedar collar ties

(subtotal not re-totaled; see Cost Ledger)

Note (Oct 1, 2026): rafters and ridge are #2 Prime KD Southern Yellow Pine (not spruce, not PT, not cedar); only the collar ties are cedar. Shingles go on a solid deck, so there is no strapping. Collar ties are fastened with Grip-Rite 2″ 13-ga stainless ring nails (see Hardware). Wood connectors are in Hardware.

Ventilation: a solid ridge plus two screened gable vents (model chosen later). Do not seal the gable ends when finishing the interior — the gable vents are what ventilate the roof space.

Superseded Oct 1, 2026 (history, Aug 11 plan: KD spruce rafters, cedar 1x8 ridge, cedar strapping, metal roofing; “+$186 over the pine spec”, the spruce 228 psi / 875 psi bending check, and the cedar-strapping screw-withdrawal and doubled edge-zone screw pattern notes). None of that applies to the asphalt roof; the original paragraphs are retired from this file.

WALL SHEATHING & WEATHER BARRIER

Felt is cap-stapled (Stinger CH38-2); no seam tape — the felt laps shed water. Shingles nail directly through the felt into plywood - no furring strips needed.

CEDAR SHINGLE SIDING

(Subtotal not re-totaled; see Cost Ledger.)

Wall area: ~292 sq ft net, ~320-335 sq ft with waste (3.2-3.5 squares)
Recommended grade: No. 2 (Red Label) or No. 3 (Black Label) for shed application

CEDAR TRIM

(Subtotal not re-totaled; see Cost Ledger.)

Shadow boards sit at the TOP of the fascia (a deliberate departure from JCS p.30, which centers them). All cedar is green: sticker it and cut joints after it settles.

Stops reverted to pine (July 2026 audit F5): they frame the accent-painted sash/doors, so they paint with them — cedar's silvering rationale doesn't apply to interior-facing stop strips.

DOORS - Pine (materials to build 5' double door)

Note (rev. July 2026): Doors are shop-built plank doors per Appendix B, each with a fixed 6-light sash lite set in the upper half (matches the wall barn sash). Salvage sash (outside frame ≤24" wide) saves ~$100 vs new. Doors kept as pine — painted/stained; cedar upgrade +$150 if desired.

SITE DRAINAGE & FOUNDATION (added July 2026)

Install collector trench 3–4" below pad subgrade BEFORE finishing gravel placement — sloped ⅛–¼"/ft to the exit corner, solid pipe out to daylight downhill. Use #57 clean stone around the pipe (crusher run has too many fines). Blocks: 6 required + 2 spare/stacking, layout per plans p.16/p.19. Termite shield goes between block and skid, 2" overhang bent down 45° (plans Appendix C). Earth anchors optional — see Optional Upgrades.

RAMP - Pressure Treated

ROOFING & DECK — 3-tab asphalt (replaces Metal Roofing, Oct 1, 2026)

(subtotal not re-totaled; see Cost Ledger)

Superseded Oct 1, 2026: 29ga corrugated metal panels (10 × $35) and metal ridge cap (2 × $25). No metal roofing.

WINDOWS & VENT

FINISHES — exposed roof structure (added Aug 11, 2026)

All of this is pre-applied on sawhorses before installation — oiling 14 rafters, the ridge and the collar ties flat at waist height is an afternoon; overhead on a ladder afterward is misery and a worse job. Cut first, finish second, install third.

INTERIOR LINER & PEGBOARD (moved into base scope Aug 16, 2026)

Finish oils (tung / Osmo) for the rafters, ridge and ceiling need re-visiting now that the rafters and ridge are SYP. Do a test board first (originally: cedar + tung, spruce + Osmo Raw, spruce + tung, spruce + matte waterborne; re-pick the species to test). One afternoon and $20 settles a ceiling you'll look at for thirty years.

HARDWARE & FASTENERS

(subtotal not re-totaled; see Cost Ledger)

WHAT YOU'LL SEE

From Outside:

• Cedar shingle walls weathering to silver-gray
• Cedar trim weathering to match
• 3-tab asphalt shingles, Weathered Gray
• Cottage/Craftsman aesthetic

From Inside:

• 4x4 posts and beams (natural wood)
• Back of plywood sheathing between posts
• Clean, uniform appearance
• Option to leave as-is or finish later

OPTIONAL UPGRADES

MAINTENANCE COMPARISON

Lifetime cost advantage of cedar: Even at similar initial price, you save $200-500+ in stain/paint over 20 years.

TOOL RECOMMENDATION

Gun chosen (Oct 1, 2026): the Freeman G2CN45 15° coil roofing nailer — to be ordered or confirmed. It fires the BHTOP 3/4″ smooth coil nails for the asphalt roof and, later, stainless ring-shank coil roofing nails (1-1/4″–1-1/2″) for the ~1,500 cedar wall-shingle nails. The earlier rent/buy options and the coil siding nailer plan are superseded. See Nail_Guns_and_Fasteners.html.

DELIVERY NOTES

• Both Home Depot and Lowe's deliver lumber orders over $45
• Cedar shingles are typically in stock (check availability)
• Schedule delivery close to build date
• Plywood re-ordered from Home Depot, delivered Oct 2 (the 7 sheets of 19/32 BCX were cancelled by Lowe's; the only line of the Sep 30 order not delivered)

MATERIALS BY STORE — removed Aug 13, 2026

Deleted. Those tables were a third roll-up of data that already has two authoritative views, and they had drifted: their subtotals summed to $4,003 against an actual $5,407, with legacy categories (Hardware $295 vs $515). A roll-up nobody recomputes is exactly what produced the old $5,228 subtotal error.

Use instead: the Summary and Detailed Breakdown above for cost; Shed_Orders.html for the three-delivery batching plan; and Order_2_Checklist.md for the current per-vendor split.

PURCHASE CHECKLIST

• Drainage: perforated + solid 4" pipe, fittings, fabric, #57 stone
• Solid 4x8x16 concrete blocks (8)
• Aluminum flashing (termite shield)
• Pressure treated framing lumber
• 3/4" (23/32") PT CDX plywood - floor (4 sheets — July 2026 audit F8 corrected this from 3)
• 15/32 Plytanium pine sheathing — walls (12 sheets) + interior liner (9 sheets)
• #30 felt, ASTM D226 Type II (~2 rolls, roofing supply, later)
• Cedar shingles (3.5 squares + starter)
• Cedar trim boards (all sizes)
• 19/32 BCX sanded plywood ×7 (roof deck; re-ordered from Home Depot, delivered Oct 2)
• ProArmor underlayment
• 3-tab shingles, 7 bundles
• Drip edge ×6
• PSCL panel clips ×12
• Loctite PL ×3
• Freeman G2CN45 + BHTOP 3/4″ coil nails (order or confirm)
• Cap stapler (Stinger CH38-2) and staples
• Barn sash windows (2)
• Wood louvered vent
• Pine boards for doors
• 6-light barn sash for door lites (2, ≤24" wide — salvage or new)
• Lite glazing kit (sealant, stainless brads, 1x3 + 1x2 stock)
• All hardware and fasteners
• Stainless ring-shank coil roofing nails for wall shingles (1-1/4″–1-1/2″, length open)

FINAL COST SUMMARY

History (superseded Oct 1, 2026 for the roof items): Revised Aug 11 2026 — exposed-roof-structure upgrade: cedar ridge/ties/strapping + KD spruce rafters (+$186), the stainless and uplift hardware it requires (+$192), and pre-finish materials (+$180). Materials +$558 → +$586 before tax with the 5% overage → +$632 with tax. Of the $558: $366 discretionary appearance (cedar strapping +$120, collar ties +$30, ridge +$22, spruce-over-PT rafters +$14, finishes +$180) and $192 hardware the species change requires (stainless roofing screws in two lengths with doubled edge density +$80, 10d stainless bump +$10, stainless 6d collar-tie nails +$18, stainless strapping screws +$55, hurricane ties +$29). Prior: interior girts +$77; door sash lites; roof members reverted to pine −$94. Prior revisions: Feb 2026 $4,282 / ~$4,625; early-July $4,653 / ~$5,025; mid-July $4,842 / ~$5,230; late-July pre-girts $4,823 / ~$5,210.

Estimate prepared February 2026
Prices are estimates based on market research - verify at time of purchase