If you want more privacy without replacing your whole fence, a trellis topper can be a practical option. Before buying materials, however, you need to check the total height, the position of the boundary and any restrictions affecting your property. The key point under fence height rules UK homeowners commonly encounter is that trellis normally counts as part of the fence’s overall height.

This guide gives practical general information for properties in England, including homes across the West Midlands. Planning rules can vary according to the property and location, so always confirm your position with your local planning authority before starting work.

What are the usual permitted fence heights?

In many cases, you can erect or alter a fence, wall or gate without making a planning application if it stays within permitted development limits. The usual maximum heights are:

One metre where the fence is next to a highway used by vehicles, including the footpath beside that highway.
Two metres elsewhere, such as many rear and side garden boundaries.

These are general limits rather than automatic permission for every property. A corner plot, unusual road layout or fence near a junction may need particular care. The meaning of “adjacent” can also depend on the site layout, so do not assume that every side fence can be two metres high.

If you want to exceed the relevant limit, you will normally need to ask the local planning authority whether planning permission is required. Approval is not guaranteed, particularly where extra height could affect road visibility, neighbouring homes or the appearance of the street.

Does trellis count towards fence height?

Yes. For planning purposes, an attached trellis topper is generally treated as part of the fence. You cannot normally place a two-metre fence on the boundary and then add another section of trellis above it while claiming that the trellis does not count.

Measure the complete structure from the relevant ground level to its highest point. This includes:

The solid fence panel or boards.
Any attached trellis topper.
A raised base where it forms part of the structure.
Any decorative top that increases the maximum height.

For example, if the permitted overall height is two metres, the solid fence and trellis together should remain within two metres unless you have the required planning permission. A lower panel with a modest topper can therefore be a safer design than adding trellis to an existing fence already at the limit.

Ground levels can complicate measurements on sloping gardens or where neighbouring land sits higher or lower. Ask your council how it will assess the height if there is any doubt.

Check the boundary before adding height

Planning limits are only one part of the issue. You should also establish who owns the fence and where the legal boundary lies. A title plan may indicate the general boundary, but it does not always identify the exact line or prove who owns a particular fence.

Check your title documents, previous property information and any agreement made with your neighbour. Do not attach trellis, battens or fixings to a neighbour’s fence without permission. Even when a fence appears to face your garden, that does not necessarily mean it belongs to you.

If ownership is unclear, speak to your neighbour before ordering or altering anything. A simple conversation can prevent a boundary disagreement. Where the exact line or ownership is disputed, take independent legal or surveying advice rather than relying on assumptions about which side has the posts.

You should also ensure posts, concrete supports and panels remain on the correct side of the boundary. K C Fencing and Timber Ltd supplies fencing materials but does not provide installation or boundary surveying services.

Other restrictions you need to consider

Permitted development rights can be limited or removed. Extra checks may be necessary if your home is:

A listed building or within the grounds of one.
In a conservation area or another designated location.
Subject to an Article 4 direction.
A newer property with restrictive planning conditions.
Covered by a covenant limiting fences or alterations.

Leasehold properties and managed developments may also have separate consent requirements. Planning permission and private restrictions are not the same: meeting planning rules does not override a covenant, lease condition or ownership issue.

Higher fencing can affect visibility for drivers and pedestrians, especially beside driveways, bends and junctions. It can also reduce daylight or create an overbearing boundary for a neighbour. Your council may consider these effects if an application is required.

Using trellis to improve privacy

Trellis can soften the top of a fence while providing extra screening. It often feels less imposing than extending the entire boundary with solid boards because light and air can pass through the openings.

Choose the style according to the level of privacy you need. A wider-spaced trellis is useful for appearance and climbing plants, while smaller openings provide more screening. Bear in mind that even close trellis will not give the same privacy as a solid panel.

You can combine a suitable trellis topper with our fence panels, provided the finished height complies with the rules applying to your boundary. Make sure the width suits the panel and that the supporting posts can accommodate the complete arrangement.

Plants can add seasonal cover, but allow for their eventual weight and movement in windy weather. Keep growth under control so it does not damage the trellis, obstruct a highway or spread beyond your boundary. Avoid relying on planting as a way to get around a planning restriction; hedges and trees are governed differently, and other legal issues can still arise.

Make sure the existing fence can support it

A topper adds weight and catches more wind. Before adding one, inspect the entire fence rather than looking only at the panel. Check for:

Loose, split or rotten timber posts.
Cracked or leaning concrete posts.
Damaged panels and weak framing.
Loose fixings or unstable supports.
Signs that the fence moves excessively in wind.

If the posts are too short, do not improvise an unstable extension. It may be better to replace posts or redesign the fence so the topper is properly supported. Our range includes concrete posts and gravel boards for suitable fencing projects.

Remember that a gravel board can affect the finished height. Measure the planned combination of gravel board, panel and trellis before ordering. Use our fence calculator to estimate quantities, then check dimensions carefully for your chosen products.

A practical checklist before you order

Measure the current fence from the relevant ground level.
Add the full height of the proposed trellis and all other components.
Check whether the boundary is adjacent to a vehicle highway.
Confirm who owns the fence and where the boundary lies.
Review title documents, covenants and property conditions.
Ask the local planning authority if the rules are unclear.
Discuss work with your neighbour where it may affect them.
Inspect posts and panels for strength and condition.
Choose materials that suit the width and construction of the fence.

Keeping measurements, product specifications and any written council advice can be useful if questions arise later.

Ask about trellis and fencing materials

K C Fencing and Timber Ltd manufactures and supplies fencing materials for trade and DIY customers across the West Midlands, with delivery available and free collection from our Wednesbury yard. We supply materials only and do not fit fencing. Call 01902 288162 or request a quote for suitable panels, posts, gravel boards and trellis options for your project.

Fence Height Rules UK: Adding Trellis Toppers Legally