Boundary walls, fences and light to a ground floor window
Part 2 Class A allows 2 metres at the rear and 1 metre next to a highway. Here is how to test light loss from a low obstruction, and what to do when the fence is lawful.
A boundary fence blocking light to a ground floor window is one of the few planning problems where the structure causing it is usually lawful. Part 2 Class A of the Town and Country Planning (General Permitted Development) (England) Order 2015 allows a gate, fence, wall or other means of enclosure up to 2 metres high, or 1 metre where it is next to a highway used by vehicles or a footway of such a highway. Below those heights, and outside a listed building curtilage, no permission is needed and the effect on a neighbour's window is not assessed by anybody.
That is the starting position. It has more exceptions than people expect.
The heights the Order allows
The 2 metre figure is measured from ground level, and where the ground is not level, from the highest part of the surface next to the structure. A 1.8 metre fence panel on a 300 millimetre plinth is a 2.1 metre structure and needs permission.
The 1 metre limit applies where the enclosure is adjacent to a highway used by vehicular traffic, or a footway of such a highway. That catches front boundaries on almost every residential street, including the returns on a corner plot, which is why so many front walls are low and so many corner fences are unlawful.
Two further exclusions. Class A does not permit a means of enclosure within the curtilage of a listed building. And the right can be removed by an article 4 direction or by a condition on the permission that created the house, which is common on newer estates where the developer's layout depends on open frontages.
Conservation areas complicate the position in the other direction. The heights are the same, but taking down an existing boundary wall above those heights within a conservation area can itself require permission, so removing a wall is sometimes more regulated than building one.
When a boundary structure needs permission anyway
Height is the usual trigger, and the two straightforward cases are a rear boundary fence above 2 metres and a front boundary above 1 metre.
Less obvious is the structure that stops being a means of enclosure. A high wall with a substantial roofed section is a building. A fence that forms one wall of a car port is part of that car port. A trellis fixed on top of a 2 metre fence counts towards the overall height, whatever the fencing catalogue says, because the Order measures the means of enclosure rather than its solid part.
And the rules say nothing at all about hedges. A leylandii hedge can reach 6 metres without any planning control applying to it, which is exactly why a separate statutory route exists for those.
Judging light loss from a low obstruction
A 2 metre fence sounds harmless until you put it 1.2 metres from a ground floor window with a low cill.
The BRE guidance in BRE 209 gives a first check that works on a section drawing. Measure from the centre of the lowest window, at the level of the internal cill, to the top of the obstruction. If the obstruction subtends an angle of less than 25 degrees above the horizontal across the whole of the obstructing line, diffuse daylight to that window is unlikely to be materially affected, and no further calculation is needed. Above 25 degrees, the fuller tests apply.
Run the geometry before running the argument. A 2 metre fence 4 metres from a window sits at about 17 degrees above a cill 800 millimetres up, which passes the initial check comfortably. The same fence at 1.5 metres sits at roughly 39 degrees and does not, so the vertical sky component test becomes relevant. Those two figures are illustrative geometry rather than a result for any particular room, and a proper assessment measures the real cill height, the real ground levels and the real distance.
Where the numbers do fall below the guideline, the vertical sky component and the 27 per cent guideline explain what the loss means, and the 0.8 relative test sets out when a reduction is treated as noticeable. Both come from the same guidance and both were written for buildings rather than fences, which is a real limitation and worth saying out loud in any objection.
Where planning stops and private law begins
If the fence is under 2 metres and outside any of the exclusions, there is no planning application to object to, no officer to persuade and no appeal.
Three private routes remain, and they are different things. A right to light can be acquired by twenty years of uninterrupted enjoyment under the Prescription Act 1832, and it is enforced through the civil courts rather than the council: the remedy is an injunction or damages, and the test is whether enough light remains for ordinary use of the room, which is not the same test as the planning guidance. A restrictive covenant on the title may limit boundary treatments regardless of planning. And where the obstruction is a line of two or more evergreen or semi-evergreen trees or shrubs over 2 metres high, the high hedges provisions in Part 8 of the Anti-social Behaviour Act 2003 let you complain to the council once you have tried to settle it directly, and the council can issue a remedial notice.
The high hedges route is slow and carries a fee set by each council, but it is the only statutory remedy most neighbours will ever have.
Retaining walls and raised ground levels
Raising the ground in a garden is an engineering operation, and engineering operations are development under section 55 of the Town and Country Planning Act 1990.
This is where boundary disputes become planning matters. A neighbour who raises a patio by 600 millimetres and builds a retaining wall with a 1.8 metre fence on top has created a 2.4 metre structure measured from your side, and the works to raise the ground are separately assessable. Overlooking, loss of privacy and the change in the relationship between the two gardens all become material considerations at that point.
The measurement question is the one that decides these cases: height is taken from the higher of the two ground levels next to the structure, so a fence that is lawful when viewed from the raised side may be unlawful from yours. Photographs with a levelling staff, taken before and after where possible, are worth more than any amount of correspondence.
Enforcement against an unlawful structure
Report it to the council's enforcement team with the height measured, the location marked on a plan and dated photographs. Enforcement is discretionary, and councils will not act where the breach is trivial or where permission would obviously be granted.
Time limits matter. The Levelling-up and Regeneration Act 2023 moves enforcement time limits in England to ten years for operational development, replacing the previous four year rule, and the date that change took effect should be checked against the date of the breach. After the limit passes the development becomes immune, and a certificate of lawful existing use can be applied for.
If the council does serve an enforcement notice, the owner can appeal to the Planning Inspectorate, which usually adds six months or more. Expect the process to be measured in seasons.
Practical remedies short of an application
Most of these disputes are resolved by a drawing rather than a decision notice.
Try the sequence in order: agree the height and the ground level with the neighbour in writing, propose a lower panel or an open-topped trellis on the section nearest the window, offer to share the cost, and only then consider the formal routes. Where the neighbour is applying for something else anyway, the amenity effect of their boundary treatment can be raised as part of that application, and our note on responding to a neighbour's daylight objection works the same ground from the applicant's side.
Where a formal assessment is needed, a Daylight and Sunlight Assessment prepared by a suitably qualified author carries far more weight than a homeowner's sketch, and councils usually expect one for anything contested. Professional review is strongly advised before it is submitted.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
How high can a fence be without planning permission?
Two metres, measured from the higher ground level next to it, or one metre where it adjoins a highway used by vehicles or its footway. Trellis and plinths count towards the height. The right does not apply within the curtilage of a listed building and can be removed by an article 4 direction or by a condition on the original permission for the house.
Can I object to a neighbour's fence on daylight grounds?
Only where the fence needs permission, which usually means it exceeds the height limits or the rights have been removed. Below those heights there is no application and no planning decision to challenge. Where ground levels have also been raised, the engineering operation is separately assessable, and that is often the stronger point to pursue.
What is the 25 degree check for daylight?
It is the first test in the BRE guidance. Measure from the centre of the lowest window at internal cill level to the top of the obstruction. If the obstruction stays below 25 degrees above the horizontal along its whole length, diffuse daylight is unlikely to be materially affected and no further calculation is needed. Above that angle, the vertical sky component tests apply.
Does the high hedges law cover fences?
No. Part 8 of the Anti-social Behaviour Act 2003 applies to a line of two or more evergreen or semi-evergreen trees or shrubs over two metres high that blocks light or access to a domestic property. Fences and walls are outside it. You must show you have tried to settle the matter with the owner before the council will accept a complaint, and a fee applies.
How long before an unlawful fence becomes immune from enforcement?
The Levelling-up and Regeneration Act 2023 moves enforcement time limits in England to ten years for operational development, replacing the earlier four year rule, and the date that change took effect should be checked against the date of the breach. Once the limit passes, the owner can apply for a certificate confirming the structure is lawful.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.