Sightlines over land you do not control

A visibility splay on third party land is not fatal to an application, but it changes how the splay has to be secured. A condition requiring you to keep land clear that you neither own nor control is unenforceable, and an officer who imposes one has created a condition that fails the tests in the Planning Practice Guidance. The workable routes are a negatively worded condition preventing development until the splay is secured, an agreement or easement with the owner, or a redesign that brings the sight line within land you do control.

Highway verge is a special case, and it is the most common one on a rural frontage.

Why control of the splay matters

A splay is only worth something if it stays clear for as long as the access is used. Planning secures that through conditions, and a condition has to be enforceable against the person who holds the land. Where the splay falls across a neighbour's garden, the authority has no mechanism against that neighbour, and your own obligation to do something you cannot lawfully do is worthless.

So the highway officer asks two questions in sequence. Is the sight line achievable at all. And can it be secured in a way that survives a change of ownership. The second question kills more schemes than the first.

Highway verge and who maintains it

Where the splay falls on highway land, including the grass verge, the position is better than it looks. The highway authority owns or controls the surface, and it has its own powers over obstructions and over vegetation, so there is nothing for the applicant to control.

That does not mean nothing needs doing. Verge maintenance regimes are cyclical and a verge cut twice a year may carry growth above sight line height for weeks at a time, so the officer will want the splay dimensions checked against the verge width and the growth likely within it. Where the verge is narrow and the sight line clips a hedge on the far boundary, you are back to third party land.

Confirm the extent of highway land in writing. The adopted highway boundary is rarely where the fence sits, and a definitive answer from the highway authority's records is worth having before the application rather than after. Our note on highway drainage, gullies and who maintains them deals with the same boundary question for drainage apparatus.

Conditions that work and conditions that fail

Conditions have to meet six tests, including being enforceable and reasonable in all other respects. Applied to splays, that produces a clear division.

The third of those is the Grampian style negative condition, and the Planning Practice Guidance treats such conditions as acceptable provided there is a reasonable prospect of the action being performed within the lifetime of the permission. Where the third party has refused in writing, that prospect disappears and the condition should not be used.

That is why the sequence matters. Approach the owner before the application, not after a committee resolution, and put their position in writing either way.

Licences, easements and agreements with the owner

Four mechanisms are used in practice, in descending order of durability.

• A deed of easement granting a right to maintain visibility over the land, registered against the title, which binds successors.
• A transfer of the strip of land itself, which is the cleanest answer where the neighbour will sell.
• A planning obligation entered into by the third party landowner, securing the splay as a covenant running with the land.
• A licence or informal agreement, which is personal, revocable and the weakest of the four.

A licence may be enough to get a negative condition discharged, and it will not reassure a future buyer. Where the access serves a dwelling you intend to sell, pay for the easement, because the question will surface again at conveyancing and solving it then costs considerably more.

Where the splay land belongs to the highway authority, a section 278 agreement for the access works can include the visibility provision, which gives the authority its own route to deal with growth.

Hedges, walls and future growth

Splays are usually lost to time rather than to construction. A hedge planted at 0.5m is at 1.5m within a few seasons, and a fence replaced by a new owner is a solid 1.8m panel.

Three things help. Specify the boundary treatment inside the splay on the approved drawings, so there is a drawing to enforce against. Choose species that are managed at low height rather than ones that want to be a hedge, and say so in the landscape details. And where a wall is proposed, design the splay around the wall rather than relying on the wall being kept low, because a masonry structure is likely to outlast the condition's memory.

The 0.6m figure is the one authorities commonly apply to obstructions within a splay, taken from driver eye height considerations. Parked cars defeat it entirely, so where the splay crosses a drive or a parking area, that conflict needs resolving on the layout.

Illustrative example: a plot on a rural lane where the required sight line to the east crosses 11m of a neighbour's beech hedge. The neighbour will not grant an easement but is willing to sell a 1.5m strip along the frontage. The applicant buys the strip, moves the hedge back, and the splay then falls wholly within the application site, so an ordinary positive condition works. Those figures are illustrative.

Alternatives where control is impossible

When the owner says no and means it, four options remain.

1. Relocate the access along the frontage to a point where the sight line falls on your own land or on highway verge.
2. Reduce the required sight line by evidencing lower actual speeds with a survey at the access location, which sometimes brings the requirement within reach.
3. Propose physical measures that reduce speeds, such as a gateway feature or a change in surface, agreed with the highway authority and secured through a section 278 agreement.
4. Use an existing shared access that already has acceptable visibility, with the intensification case made properly.

The speed survey route is the one most often overlooked. Requirements derive from measured speeds rather than from the posted limit, and on a lane where traffic moves at around 24mph the sight line needed is much shorter than the one calculated from a 60mph national limit.

Evidence that satisfies the highway officer

A submission that answers the control question up front avoids a holding objection.

• A topographic survey showing levels along the frontage and across the splay, since a crest or a dip changes everything.
• A splay drawing with the setback, the sight line distances, the driver eye height and the object height stated.
• An ownership plan showing the application site in red, land controlled by the applicant in blue, and the splay land identified separately.
• The correct ownership certificate, with notice served on any third party owner whose land is included.
• A speed survey where the posted limit and the likely speeds differ.
• Correspondence with the third party owner, and with the highway authority on the extent of adopted land.
• The proposed boundary treatment and planting within the splay.

A Transport Statement is the proportionate place for that material on a single plot or small scheme, and a full Transport Assessment where the scale demands it. Where the access question is the main planning issue, a Planning Statement should address the condition mechanism directly rather than leaving the officer to invent one.

You can see which supporting documents your site is likely to need by entering the postcode on PlanScope.

This is general guidance, not legal advice. Visibility standards and condition practice vary between highway authorities, so confirm the position with yours before relying on it, and take legal advice on any easement or obligation.

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