How do I fix trellis to a fence?

Use galvanised trellis clips or treated timber battens screwed into the fence posts, not the panels. For face-fixing, drive 4.5 × 50mm screws through the trellis frame into the post — minimum two per side, typically 6–8 screws per 1.83m-wide panel. Leave a 25–50mm gap behind the trellis so climbers can twine through.

Can trellis increase fence height?

Yes — adding trellis on top of an existing fence is common, but the combined fence-plus-trellis height counts as a single structure under permitted development. A boundary adjoining a road must stay below 1m; any other boundary below 2m, or you need planning permission.

What sizes are available?

Standard UK trellis is 1.83m (6ft) wide and sold in finished heights of roughly 0.3, 0.6, 0.9, 1.2, 1.5 and 1.83m (Jacksons Fencing). You buy the height you want as one panel — you do not stack short panels to build up height. Square and diamond lattice patterns are both common.

How many trellis panels do I need?

Panels run along the length only: divide the wall or fence run by the panel width (1.83m as standard) and round up. For a 3m run that is two panels. Choose the panel height to match the screening you want — taller panels do not need more posts or panels per metre.

What are the best climbing plants for trellis?

Clematis, honeysuckle and jasmine are popular for scent and flower. For evergreen screening use ivy, star jasmine (Trachelospermum) or evergreen clematis. For an edible crop try climbing French beans, runner beans, peas or a grape vine on a warm, sunny aspect.

GardenCalcs

Trellis Calculator — Panel Quantities & Fixings

Work out trellis panel quantities and fixing requirements.

Wall/Fence Length

Total length of wall or fence to cover, measured along the run; deduct gate or door openings you won't trellis.

Trellis Height

Finished trellis height — pick a standard panel size (0.3/0.6/0.9/1.2/1.5/1.83m). On top of an existing fence, keep the combined height under 2m for permitted development.

How We Calculate This

Panels needed = ceil(Wall/Fence Length ÷ Panel Width). Trellis comes in the finished height you choose, so you count panels along the run only — taller trellis does not change the count. Each panel takes about 6–8 fixing screws (minimum two per side).

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.