Shed / Outbuilding Cost Estimator
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How it works
Sheds come in three economies: DIY kits ($25–35/sq ft in materials — you supply weekends), pro-installed kits ($50–65/sq ft, up in a day or two), and custom-built ($80–120/sq ft, matches your house, lasts decades).
The foundation decision matters more than people think. A gravel pad is cheap and drains well; a concrete slab costs 3–5x more but gives you a clean floor for a workshop. For anything with heavy equipment, piers or a slab beat skids on dirt.
Size creep is the classic mistake: a 10×12 looks big in the store and small once the mower, bikes and tools move in. Buy 25% bigger than you think — the cost per square foot falls as sheds grow.
Frequently asked questions
Is it cheaper to build a shed or buy a kit?
Kits are cheaper for standard sizes — factories buy lumber in bulk. Custom building wins when you want specific dimensions, taller walls, or siding that matches your house.
What size shed do I need?
A riding mower plus basic tools fits in 10×12 (120 sq ft). A workshop wants 12×16+. Measure your biggest items, lay them out on paper, then add 25% — sheds always fill up.
Do I need a permit for a shed?
Usually above 120 sq ft, but rules vary wildly — some cities require permits at any size, others exempt up to 200 sq ft. Call your building department; it is a 5-minute question that avoids a fine.
Gravel pad vs concrete slab?
Gravel ($400–800) drains well and is fine for storage. A slab ($2,000–4,000+) gives a level, cleanable floor for workshops and heavy equipment. In frost zones, piers below the frost line beat both.
How much does electrical add?
Basic lights and outlets: ~$800 if a circuit is nearby. A full subpanel with heat: $2,000–3,000+. Trenching across the yard is the wildcard — get it quoted.
What siding lasts longest?
Metal and fiber-cement: 30–50 years nearly maintenance-free. Cedar looks great but needs restaining every 3–5 years. T1-11 is cheapest but plan on paint every 5–7 years.
Can a shed add property value?
A quality shed adds modest value ($1,000–5,000 appraised) and real buyer appeal. A rotting lean-to subtracts — appraisers notice.
How do I keep it from rotting?
Keep wood 6+ inches off soil, ensure the site drains away from the shed, ventilate (gable vents or a ridge vent), and use pressure-treated skids or a proper foundation.
Kit delivery — what should I expect?
Most kit companies offer curbside delivery; carrying 16-ft wall panels to the backyard is on you. Check gate and fence clearances before ordering — returns are painful.
Can I put a shed on a slope?
Yes — with piers or a retaining-wall foundation. Budget an extra $500–2,000 for leveling work. Never just shim one side; it settles unevenly.