Reports for a site with a Tree Preservation Order

A Tree Preservation Order changes the order in which work happens on a site. The survey comes before the layout, the constraints plan comes before the house is drawn, and the arboricultural assessment reports on a design that has already responded to the trees. Search for tpo site development reports and the list looks short. The sequence is what matters, and getting it wrong is the most expensive mistake a self-builder makes on a wooded plot.

Protected trees are controlled under the Town and Country Planning Act 1990 and the tree preservation regulations. Cutting down, topping, lopping, uprooting, wilfully damaging or wilfully destroying a protected tree without consent is an offence, and damage includes severing roots during construction.

Confirming the Order and what it covers

Start with the Order itself rather than with a map layer. Ask the council for a copy of the Order, its schedule and its plan. The schedule says whether protection applies to individual trees, groups, areas or woodland, and each category behaves differently.

An area designation protects the trees that were present when the Order was made, which can be difficult to establish decades later. A woodland designation protects the woodland as it stands, including trees that have grown since. Individual designations are numbered and mapped, and the numbering is what you will use in every later document.

Check for conservation area status at the same time. Trees in a conservation area with a stem diameter above the threshold in the regulations are protected without an Order, and works require six weeks written notice to the council, during which it can make an Order.

Then check whether the trees you care about are on the site at all. Trees on neighbouring land, with crowns and roots extending over the boundary, constrain a layout just as effectively and carry the same protection.

The survey and the categories

The recognised British Standard for trees in relation to design, demolition and construction sets the method. A qualified arboriculturist records each tree or group with its species, height, stem diameter, crown spread by compass point, height of crown clearance, age class, physiological and structural condition, estimated remaining contribution in years, and management recommendations.

Each tree is then placed in a category. High quality trees, moderate quality trees, low quality trees and those unsuitable for retention. The category determines how hard the layout has to work to keep the tree, and category U trees can usually be removed with the council's agreement even where they are protected.

The root protection area is calculated from stem diameter, as a radius of twelve times the diameter, with a cap for single-stem trees. It is then plotted as an area which may be adjusted in shape, though not in total, to reflect soil conditions, existing structures and the likely root distribution. The calculation and its adjustments are worked through in root protection area calculations in an arboricultural impact assessment.

That survey is the Tree Survey the council expects, and it has to be done at a time of year when the trees can be assessed properly.

The constraints plan comes before the layout

This is the step that gets skipped, and skipping it is why so many schemes come back from the council with an arboricultural objection.

The constraints plan takes the survey and draws, on the site plan, the root protection areas, the existing crown spreads, the shade patterns and the future crown spread allowing for growth. What is left is the developable area.

Design into that area. A house positioned so that its foundations sit within a root protection area, with a driveway crossing another, cannot be fixed by a better report. It can only be redrawn or refused.

Two constraints are routinely forgotten. Shade and the perception of pressure from a large tree over a garden generate later applications to fell, which councils know and weigh at the application stage. And service runs, drainage, soakaways and level changes all have to sit outside root protection areas or use a technique that avoids excavation.

The Arboricultural Impact Assessment

Once the layout responds to the constraints, the assessment reports on what remains.

It identifies the trees to be removed and why, by reference to their category and the design, quantifies the encroachment into any root protection area and justifies it, assesses the effect on retained trees during and after construction, and sets out the mitigation and replacement planting. On PlanScope the Arboricultural Impact Assessment and the tree survey share a single report page, because the two documents are prepared from the same field data.

Encroachment is the section officers read closely. A small incursion into the outer part of a root protection area, on a tree in good condition with a large area overall, using a no-dig construction, is usually acceptable. An incursion close to the stem is not, whatever the construction technique.

The detail of how those areas are handled in practice is covered in root protection areas in an arboricultural impact assessment.

Where the objection usually comes from

Council tree officers object on a small number of recurring grounds, and each is avoidable.

The first is a layout that leaves no long-term future for a retained tree. A large oak two metres from a new kitchen window will generate a felling application within five years, and the officer knows it. Retention has to be plausible, not nominal.

The second is a level change. Lowering ground within a root protection area kills roots as effectively as trenching, and raising ground over them suffocates them. Both are frequently absent from the tree documents because they appear only on the engineering drawings.

The third is the construction access. A site with one entrance that runs through the root protection area of the best tree on the plot is a problem that shows up on day one, and it belongs in the method statement rather than being discovered on site.

Method statement and tree protection plan

The arboricultural method statement describes how the works will be carried out around retained trees: the sequence, the construction techniques within root protection areas, the treatment of level changes, the storage and mixing areas, and the supervision regime with named hold points.

The tree protection plan is the drawing that goes on site. It shows the protective barrier positions, the specification of the barriers, the ground protection within working areas, and any exclusion zones.

Fencing specification matters because it is what the site actually builds, and a plan showing plastic mesh where the standard expects a rigid barrier will be enforced against. Our note on tree protection plans and fencing specification covers the detail.

Both documents are normally secured by condition, along with a requirement for arboricultural supervision at defined stages and for a site monitoring record.

Consent for works, replacement planting and conditions

Works to a protected tree need the council's consent on the relevant application form, which is separate from planning permission. Where the works are part of a scheme with permission, the permission itself can authorise the removal of protected trees where that was clearly part of what was approved, so describe tree removal explicitly in the application rather than leaving it implicit in a drawing.

Exemptions exist for dead trees and for work needed to remove an immediate risk of serious harm, with a notice requirement. They are narrow, and relying on them without a written arboricultural opinion is a risk.

Expect conditions requiring replacement planting with species, size, position and a replacement period, tree protection in accordance with the approved plan, no excavation or storage within protected areas, and supervision. A Landscape Strategy setting out the planting and its establishment maintenance answers the first of those before it is asked.

PlanScope drafts the planning documents that accompany the arboricultural work and flags the survey inputs it cannot verify, which have to come from a qualified arboriculturist working to the British Standard.

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.