Framing, sheathing and slab quantities for a detached garage.
Estimates are planning aids, not a professional quote. Double-check quantities and product coverage — and any local code or permit requirements — before you buy.
⚠ A detached garage virtually always requires a permit, engineered (stamped) trusses, and footing/foundation inspections. Use this as a planning and budgeting takeoff — your building department sets the real requirements.
| Lumber & Decking | $1,949–$2,637 |
| Concrete & Footings | $1,809–$2,448 |
| Siding & Trim | $1,360–$1,840 |
| Roofing | $1,304–$1,764 |
| Doors & Windows | $1,114–$1,507 |
| Fasteners & Hardware | $257–$347 |
| Soil & Fill | $241–$327 |
| Membrane & Fabric | $136–$184 |
| Connectors & Brackets | $84–$114 |
| Total | $8,254–$11,167 |
Excludes tools, delivery, tax and permit fees. Labor not included — this is a DIY materials estimate.
These are affiliate links: we may earn a commission if you buy through them, at no extra cost to you. It never changes what the calculator recommends — the shopping list comes from your dimensions, not from what pays.
About this calculator
Enter a footprint, wall height and door count and you get a full takeoff for a detached, slab-on-grade garage: the concrete and rebar, wall framing and plates, garage-door headers, sheathing and siding, engineered roof trusses, roofing, the overhead and service doors, plus every fastener and connector — with tools, a cost range and a build time.
Choose one to four overhead doors, 8–10 ft walls, gable pitch and siding, and the materials list scales with the structure. Open advanced options for slab thickness, gravel base, a service door, windows and waste. This is a budgeting takeoff — a garage needs a permit and engineered components.
Step by step
A step-by-step walkthrough to go with your plan above. Follow the product instructions and any local code or permit requirements as you work.
Pull the permit with your foundation and stamped truss drawings, call 811, then strip topsoil and rough-grade the pad. Everything downstream assumes a permitted, properly located footprint.
Lay and compact the gravel base in lifts with a plate compactor, set the perimeter forms dead level and square (check the diagonals), and place the rebar grid on chairs over the vapor barrier.
Pour the ready-mix, screed it to the forms, bull-float, then edge, groove control joints, and trowel to the finish you want. Set the anchor bolts in the wet edge before it sets up.
Build each wall flat on the slab — studs, the big garage-door headers, and openings — then stand it, anchor the PT bottom plate to the bolts, and brace it plumb. Tie the walls together with a double top plate.
Lift the trusses up, set the gable ends first, then fill in at 24 inches on-center. Add the temporary and permanent bracing the truss drawings call for, and tie every truss to the plate with a hurricane tie.
Sheathe the trusses, run drip edge and underlayment, and shingle from the eave up. Add fascia and vented soffit so the roof breathes.
Sheathe or wrap and side the walls, set the overhead door track and door per the manufacturer's instructions, and hang the service door and windows. Keep rough openings exactly to spec.
Add corner trim, caulk and flash the openings, and call for your framing and final inspections. Tackle electrical under its own permit once the shell passes.
Equip the job
Hand-picked categories that match the shopping list above. Links open a current selection so you can compare brands and prices.
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Decks & Structures
Answers
Almost always, yes. Garages are large permanent structures, so building departments require a permit, a designed foundation, and stamped (engineered) roof trusses, with inspections at the footing, framing and final stages. Adding electrical means an electrical permit too. Treat this planner as a budgeting takeoff and confirm requirements before you build.
A 4-inch slab over compacted gravel handles cars and light trucks for most home garages. Go to 5–6 inches, with a thickened edge and rebar, if you'll park heavy trucks, an RV, or use a lift. The planner figures concrete in cubic yards with a thickened edge so you can order ready-mix — order a touch extra rather than run short mid-pour.
Engineered trusses are faster, stronger and usually required for a clear-span garage roof, and they arrive ready to set at 24 inches on-center. The planner counts trusses by your depth and sizes the rest of the roof from your pitch. Order them from a truss supplier with stamped drawings sized for your span and local snow load.
Parts of it, but not safely all of it. The slab pour and finishing is time-critical, standing tall walls and especially setting trusses need multiple people or equipment, and roof work is at height. Budget for a small crew or sub out the pour and the roof. The build-time estimate assumes a three-person crew.