Pergola planner

Indicative only — always check the maker's drawings, ratings and instructions.

How the planner works

• Furniture space. A dining set is the table plus 0.9 m on each side so chairs can be pulled out. A corner sofa set is the sofa plus a 0.6 m walkway. These are our rules of thumb, not a standard. Use a custom footprint if you have measured your own furniture with chairs pulled back.
• Nominal and post-to-post size. Kits are sold by a nominal size, usually the outer frame or roof. The posts sit inside that. The planner takes 15 cm off each side for posts and frame, then picks the smallest common kit size whose inside space holds your furniture. Real post sizes vary: read the maker's drawing. See what size pergola.
• Traffic light. It reads your height and boundary distance against the outbuilding limits on the Planning Portal outbuildings guide: 2.5 m overall within 2 m of a boundary, 2.5 m eaves, 3 m overall elsewhere (4 m only for a dual-pitched roof). It also reminds you about the front of the house, the 50% coverage limit and designated land. It always ends with "check with your council if in doubt", because it cannot see your deeds, your conservation area or an Article 4 direction.
• Cost. Each line shows a band only when we read a retailer or maker page for it on 13 November 2026, with the link. Lines we could not price say "get a quote" and are left out of the total, rather than filled with a guess.
• Checklist. The questions to put to a supplier before you pay a deposit.

What it does not do

It does not work out a wind or snow rating, a fixing schedule or a foundation design. Those come from the maker's instructions and, for anything unusual, a structural engineer. It does not tell you that you can skip planning permission. It is England-only on planning: Scotland, Wales and Northern Ireland differ.