Keeping a protected tree in a new dwelling's garden

A protected tree in a new garden is the layout decision most likely to lose a case officer, and the reason has almost nothing to do with construction damage. Officers have watched enough schemes reach occupation to know what happens next: the new owner finds the garden dark, the gutters full and the children's trampoline permanently in shade, and an application to fell arrives within three years. Section 197 of the Town and Country Planning Act 1990 puts them under a duty to secure the preservation of trees when granting permission, and they take a long view of it.

So the case has to be made on what the garden will be like to live in, not on the tree protection fencing.

Why officers distrust trees inside private gardens

A tree in a communal green, a verge or a shared courtyard has an owner with a maintenance budget and no personal grievance against it. A tree in a private back garden has an owner who pays for the pruning, clears the leaves and loses the afternoon sun.

That asymmetry is the whole problem. The same tree, in the same condition, is far more likely to survive in shared space than in a plot boundary garden.

Officers also know that future pressure for removal is a material consideration they can weigh at the application stage, and that once the dwelling is built the balance shifts. A refusal of consent to fell can be appealed, compensation provisions exist in limited circumstances, and a council that has approved a house with an unworkable garden is in a weak position to argue the tree should stay.

Treat that scepticism as the starting point of the design, not as an obstacle at the end of it.

Usable garden space around a mature canopy

The calculation that persuades is the one that shows how much of the garden is actually usable, after the root protection area, the canopy shade and the future growth of the tree are taken into account.

Do it properly. Measure the plot's private amenity space against the policy requirement in the adopted local plan. Then overlay the root protection area calculated to BS 5837:2012, the existing canopy spread, and a reasonable allowance for growth over the design life of the dwelling. What remains, outside all three, is the space a household can lay out as a lawn, a patio or a play area.

Then run sunlight to the garden at the equinox. A garden that receives two hours of sun across at least half its area on 21 March reads very differently from one that does not, and BRE guidance gives you the test.

If the answer is that the usable garden is a strip beside the fence, change the layout. Moving one plot boundary by three metres is a far smaller intervention than defending an unworkable garden through committee.

Boundary positions and shared root areas

Trees that sit on a new plot boundary create the worst of both worlds. The root protection area spans two gardens, so neither household controls it, and any future works require agreement between owners who may not be on speaking terms.

Where the tree has to sit within the residential part of the scheme, aim for one of three arrangements.

• Wholly within a single plot, with the whole root protection area inside that plot, so responsibility is unambiguous.
• Within communal or public open space maintained by a management company or the local authority, with the root protection area entirely in that space.
• In a landscape buffer along the site edge, outside the private curtilages altogether.

Splitting a root protection area across a boundary fence line is the arrangement to avoid. If it cannot be avoided, the fence should be a post and rail or a permeable boundary set outside the protected area rather than a close-boarded fence on concrete spurs driven through it.

Ownership, maintenance and the application that comes later

Say who will maintain the tree, and fund it, in the supporting documents.

Where a management company holds the landscape areas, the tree can be listed in the schedule of maintained assets with an inspection frequency, and the service charge covers the work. Where the tree sits in a private garden, the honest position is that maintenance falls to the householder, and the scheme should acknowledge that rather than glossing over it.

A Landscape Strategy that sets out the management arrangement plot by plot is more convincing than a statement that the tree will be retained. It also gives the council something to hold a future applicant to.

Expect the later application anyway. What the evidence base does is make it harder to argue that the tree is unreasonable to live with, because the original submission already showed the garden works.

Conditions that remove permitted development rights

Permitted development is the mechanism by which retained trees are quietly lost. An extension under Class A, an outbuilding under Class E, a patio laid across the root protection area, a change of levels: none of these needs an application, and all of them can kill a tree.

Where a tree is retained inside a residential curtilage, ask for a condition removing the relevant rights rather than waiting for the council to propose one. Applicants resist this and they should not, because it is the condition that makes the tree defensible.

Pair the condition with a requirement that no change in ground levels occurs within the root protection area, and with a landscape plan showing the surfacing specification where any hard surface falls close to it.

Designing the garden so the tree survives occupation

Practical design moves do more than any condition.

Put the patio and the main seating area on the sunny side of the plot, away from the canopy, so the household is not competing with the tree for the one usable space. Use no-dig construction for paths and terraces that fall within the protected area. Lay the garden out so the mower does not have to work under the crown. Specify a permeable, unsealed surface beneath the canopy, mulched rather than turfed, since grass fails in dry shade and a failing lawn is a reason people give for wanting the tree gone.

Handle the construction period properly too, along the lines set out in retaining a tree through a construction programme. A tree that emerges from the build with a damaged crown or a compacted root zone declines slowly, and the decline becomes the argument for removal five years later.

The evidence that makes the case

Submit a Tree Survey to BS 5837:2012 with category grading, an arboricultural impact assessment of the layout, a tree protection plan, shadow diagrams at the equinox, and the usable garden area calculation described above. Add the maintenance arrangement.

Where the tree's condition is contested, deal with it openly rather than leaving the officer to ask, and note that decay or damage claims run on their own evidence, as with trees and subsidence claims.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified arboriculturist 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.