How far apart should pergola rafters be?

Rafter spacing sets your shade coverage — tighter spacing means more shade and more lumber. The calculator converts your spacing into rafter count, slat count and hardware.

Should posts be set in concrete or on anchors?

Concrete-set posts are the stiffest option; surface anchors suit existing patios and slabs. Both change the footing and hardware lines in your estimate.

Are the material costs accurate for my area?

Costs are regional estimates only, indexed by ZIP against national material averages. Always confirm current prices with your supplier before buying — the numbers here are for planning and budgeting, not a quote.

Do I need to confirm my measurements first?

Yes. The calculator asks you to verify key dimensions before it will produce material, cut, or shopping lists, because a single mistyped dimension changes every quantity downstream.

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Pergola · Step 1 of 5 · Footprint

How big is the pergola?

12×10 is the classic patio-sized pergola. Anything past 14ft on a side and beams need doubling up.

Length

Width

Post height above ground

Live estimate

Prices for your area

Enter your ZIP to re-price materials, or keep national averages.

Reviewed weekly · price book updated 2026-07-27See what changed

DIY vs. hiring a pro

Free

Save about $2,303 (59%)

building this pergola yourself.

You build it$1,588

Materials only, your sweat.

A contractor builds it$3,891

Typical bids land $3,424–$4,591.

Materials: $1,985
Labor: $1,906
Est. hours: 35

Contractor figures assume a $55/hr blended labor rate (national average). Estimates only — use them to sanity-check a bid, not as a quote.

Cut-list optimizer

Free

Buy 42 boards · 3% offcut

424 linear ft purchased, 412 ft used — 12 ft ($45) left over.

24 × 2 × 2 @ 8'
Top slats · 1 piece per board
0 ft scrap (0%)
10 × 2 × 8 @ 12'
Rafters · 1 piece per board
0 ft scrap (0%)
4 × 2 × 10 @ 16'
Beams · 1 piece per board
8 ft scrap (13%)
4 × 6 × 6 @ 12'
Posts · 1 piece per board
4 ft scrap (8%)

Estimates only. Includes a 1/8" blade kerf per cut. Measure your own site and check board lengths at the yard before buying.

Pergola rafter span10 ft vs 14.5 ft max span (2x8 @ 16" o.c.)
2x8 rafters at 16" o.c. comfortably span your 10 ft width.

This is an automated sanity check against published residential span guidance — estimates only, not a stamped engineering review. Local code and your inspector always govern; confirm sizing and embedment with your building department before you build.

Check a contractor bid

Free

Enter what a pro quoted you. We'll break it down against this project's materials and national labor rates.

Bid totalMaterials (optional)Labor (optional)

$1,588

incl. 10% waste

Materials

Area: 120 sqft
Posts: 4
Rafters: 11
Slats: 27
Concrete bags: 16

Pergola calculator questions

Common questions about this takeoff. All output is an estimate only — confirm quantities and prices before you buy.