Permitted development on a site with a tree order

Permitted development and tree protection are two separate consent systems, and the first does not give you the second. If your garden holds a tree covered by a Tree Preservation Order, your permitted development rights let you build the extension but say nothing at all about the tree. Cutting roots, pruning branches or felling still needs written consent from the council under the Town and Country Planning (Tree Preservation) (England) Regulations 2012. Householders find this out late and expensively, because the exemption that normally lets you do tree work to build something applies to planning permission granted on an application, and it excludes permission granted by a development order.

Two regimes, one garden

Schedule 2 Part 1 of the GPDO 2015 grants the householder rights most people mean by permitted development: a rear extension within the depth and height limits, a loft conversion with a rear dormer, a garden outbuilding, a porch. None of those rights mentions trees, because the Order deals with development and a Tree Preservation Order deals with the tree.

Regulation 14 of the 2012 Regulations lists the exceptions where no consent is needed. One covers work necessary to implement a planning permission, and its wording specifically carves out outline permission and permission granted by a development order. Permitted development is permission granted by a development order. So the exception does not help you.

This mirrors the position with wildlife. Just as permitted development does not authorise disturbance of a protected species, it does not authorise a single cut to a protected tree. The parallel regimes run independently, and a breach of either is an offence in its own right whatever the planning position.

Getting consent for works to a protected tree

Consent is applied for on the council's tree works form, which asks for the tree, the works proposed and the reason. Determination normally takes eight weeks. There is no fee. A refusal, or a consent with conditions you cannot live with, can be appealed to the Planning Inspectorate within 28 days.

What makes an application succeed is the reason given. "In the way of the extension" is not a reason a tree officer can grant on. Reasons that work are arboricultural: the tree is in decline, it has a structural defect, the works proposed are proportionate pruning to British Standard specification, or the removal is accompanied by a replacement of appropriate species in a position where it can grow to maturity.

A small number of situations need no consent at all. A dead tree may be removed after five working days notice to the authority, except in an emergency. Work urgently necessary to remove an immediate risk of serious harm is exempt, with notice as soon as practicable afterwards. Statutory undertakers have their own exemptions. Each of these is narrow, and the burden of proving that an exemption applied falls on the person who did the work.

Foundations inside a root protection area

The root protection area is the bit that catches householder projects. Under BS 5837:2012, the area to be protected around a single stem tree is calculated from the stem diameter, using a radius of twelve times that diameter and then adjusted for site conditions and the tree's tolerance. For a mature oak with a 700 mm stem, that is a radius of over eight metres, which will often reach well inside the footprint of a rear extension.

Digging a conventional strip footing across that area severs roots and can be caught by the offence of wilfully damaging a tree in a manner likely to destroy it, even if the tree stays standing for another five years. The engineering answers are established and none of them is exotic:

• A cantilevered slab or ground beam spanning the protection area, bearing on piles or pads outside it.
• Screw piles or mini piles installed with hand-dug root exploration and no vibration.
• A no-dig cellular confinement build-up for hard surfaces, which keeps the existing soil level and avoids excavation.
• Relocating the foundation line, which is usually cheaper than any of the above.

Shrinkable clay adds a second constraint in the opposite direction. Warranty provider guidance sets minimum foundation depths near trees to deal with heave and desiccation, and those depths increase with the tree's mature height and water demand. So you may be told to go deeper by the structural engineer and shallower by the arboriculturist. Resolving that tension is a design exercise, not a debate to have on site with a digger waiting.

Trees in a conservation area

If the tree is in a conservation area but not subject to an Order, a different route applies. Section 211 of the Town and Country Planning Act 1990 requires six weeks written notice to the authority before carrying out work to a tree above 75 mm diameter measured at 1.5 metres above ground level. The threshold rises to 100 mm where the work is thinning to help the growth of other trees.

During those six weeks the council can make a Tree Preservation Order, which is what frequently happens when a notice arrives alongside a visible building project. After six weeks with no Order and no refusal, the work may proceed, and the permission lasts two years.

Conservation area status brings other overlays worth checking at the same time, because householder permitted development is restricted there. The position is tighter again where the property sits within the curtilage of a listed building, and it is worth being clear about where your curtilage actually ends before assuming the tree is yours to deal with.

When the extension effectively requires removal

Sometimes the honest position is that the scheme and the tree cannot both exist. At that point the strategy changes.

An application to fell a protected tree so that a permitted development extension can be built is weak, because the council can point out that the extension is optional. An application for full planning permission for the extension, made together with a tree works application, is stronger in one respect: the planning balance lets the officer weigh the benefit of the development against the loss of the tree, and a condition can secure replacement planting. It is slower and it costs a fee, but it puts the two decisions in front of the same officer.

An illustrative example. A rear extension on a 1930s semi, 3.5 metres deep, with a Category B lime on the boundary and a protection area extending 2 metres into the proposed footprint. The householder could build under Part 1 but cannot lawfully touch the roots. The workable answer was a cantilevered ground beam on two piles outside the protection area, hand-dug inspection pits, a supervised dig, and no tree application at all. The extra structural cost was real and the alternative was a refused felling application and a stalled build.

Where a full application becomes the better route, a planning statement that addresses the tree loss and the replacement directly will do more for you than a longer set of drawings.

What the tree officer will ask for

Expect a request for a tree survey to BS 5837:2012 covering every tree on or adjacent to the site, with species, stem diameter, height, condition, estimated remaining contribution and a retention category. On top of that:

1. A tree constraints plan showing protection areas and shade patterns against the proposed layout.
2. An arboricultural impact assessment identifying every tree affected and quantifying root loss.
3. An arboricultural method statement with the construction sequence, foundation detail and exclusion measures.
4. A tree protection plan showing fencing positions, ground protection and service routes.
5. A schedule of supervision, naming the stages at which the arboriculturist attends site.

Councils expect a suitably qualified author for this work, and professional review is strongly advised. Survey work can be done at any time of year, though canopy condition is best assessed in leaf, which is worth remembering if your programme runs through winter.

Offences, fines and replacement duties

Cutting down, uprooting, wilfully destroying or wilfully damaging a protected tree in a manner likely to destroy it is an offence under section 210 of the 1990 Act, and on summary conviction the fine is unlimited. Other contraventions, such as unauthorised topping or lopping that does not destroy the tree, attract a lower scale fine.

Section 206 then imposes a duty to plant a replacement tree of appropriate size and species in the same place, and that duty attaches to the landowner rather than to whoever wielded the chainsaw. A council can enforce it by notice. Contractors are prosecuted as well as owners, which is why a competent tree surgeon will ask to see the consent before starting.

Sequencing consent before you start

Order the work like this. Commission the tree survey before the drawings are finalised. Establish the protection areas and test the footprint against them. Where roots are affected, design the foundation solution and get the method statement written. Apply for tree consent, or serve the section 211 notice, and allow the full statutory period. Only then set a start date.

Eight weeks for a tree application and six for a conservation area notice are not long in the context of a build programme, but they are fatal if discovered in week one of the groundworks. And a Lawful Development Certificate is the only formal way to confirm that the extension itself is lawful development, which is worth having in the file if you ever sell.

Enter your postcode on PlanScope to see which reports your site is likely to need. 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.