What size trellis panels are available in the UK?

Standard UK trellis panels are 1.83m (6ft) wide, matching standard fence panels. They come in various heights: 0.3m (1ft), 0.6m (2ft), 0.9m (3ft), and 1.83m (6ft). The most popular size for fence toppers is 1.83m x 0.3m or 1.83m x 0.6m. For freestanding garden screens, the full 1.83m x 1.83m panels are commonly used.

How do I attach trellis to the top of a fence?

Trellis is attached to fence posts using trellis clips (also called U-brackets or fence panel clips). You need two clips per panel — one on each post. For concrete posts, use clips that bolt around the post. For timber posts, screw-fix clips or simply screw through the trellis frame into the post. Always use galvanised or stainless steel fixings.

Will adding trellis to my fence need planning permission?

In England and Wales, if adding trellis to an existing fence takes the total height above 2 metres, you may need planning permission. For fences fronting a highway, the limit is 1 metre total. For example, a 1.83m (6ft) fence with a 0.3m trellis topper would be 2.13m — technically over the 2m limit. Check with your local council if in doubt.

What is the best trellis for climbing plants?

Diamond (diagonal) pattern trellis is best for climbing plants as it provides more attachment points at various angles. Square pattern trellis is better for a clean, modern look. For heavy climbers like wisteria or climbing roses, use heavy-duty trellis with thicker laths (at least 25mm). Pressure-treated softwood is the most common material, while hardwood lasts longer.

Can trellis be used as a freestanding screen?

Yes, trellis panels can be used as freestanding garden screens for privacy or to create garden rooms. They need their own posts, set in concrete at 600mm deep minimum. Use 75x75mm or 100x100mm timber posts. Freestanding trellis catches the wind, so ensure posts are well concreted in. For exposed sites, consider using lattice with wider gaps to allow wind through. Use our concrete for fence posts calculator (/fencing/concrete-for-fence-posts-calculator/) to work out the postcrete needed for each post.

Trellis Calculator — Panels, Clips & Posts for Garden Trellis UK

Trellis Calculator — Panels, Clips & Posts

Calculate how many trellis panels, clips and posts you need. Works for fence toppers and freestanding trellis screens.

Total Length of Trellis Needed

Total run length for trellis panels

Trellis Panel Size

Width × Height

How will the trellis be used?

Clips needed to attach to posts

Include wastage allowance

Adds 10% extra for cutting waste or breakages

Wastage Percentage

10% recommended — trellis can be fragile

Price Per Trellis Panel (optional)

Enter your supplier price for a cost estimate

How We Calculate This

Our trellis calculator divides your total required length by the trellis panel width to determine the number of panels needed. It then calculates the fixings or posts required depending on whether you are using trellis as a fence topper or freestanding screen.

The formula

Panels = Total length ÷ Panel width (rounded up)
Fence topper: Clips = Panels × 2
Freestanding: Posts = Panels + 1

For example, a 10m run of 1.83m × 0.6m trellis as a fence topper: 10 ÷ 1.83 = 5.46, rounded up to 6 panels. You would need 12 trellis clips (2 per panel).

Fence topper vs freestanding

Fence topper: Trellis sits on top of existing fence panels, attached to posts with clips. Adds height and supports climbing plants. Keep total fence + trellis height under 2m to avoid planning permission
Freestanding: Trellis panels between their own dedicated posts, set in concrete. Ideal for garden dividers, screening, or plant supports away from fences

UK trellis tips

Standard trellis widths are 1.83m (6ft) to match UK fence panels
Always use pressure-treated timber trellis for outdoor use
Pre-drill screw holes in trellis frames to prevent splitting
For a natural look, let climbing plants cover the trellis over 1-2 growing seasons

Frequently Asked Questions

Last updated: February 2026

All calculations are estimates. Verify with your supplier.

Trellis Calculator — Panels, Clips & Posts

How We Calculate This

The formula

Fence topper vs freestanding

UK trellis tips

Frequently Asked Questions

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