A tree survey is the assessment a suitably qualified arboriculturist carries out when a development might affect trees. In UK planning it almost always means a survey done to BS5837:2012, the British Standard for trees in relation to design, demolition and construction. Get it right and your application sails through validation; get it wrong — or skip it — and the council can refuse to register the application at all. This hub explains every report in the stack, when each is needed, what they cost, how to tell whether a tree near you is legally protected, and why the answer depends heavily on which council you are dealing with.
Why trees stop planning applications
Trees are one of the most common reasons an otherwise sound application stalls. The reason is a distinction most homeowners miss: BS5837 is guidance, not law. The word "Recommendations" is in the title deliberately, and the standard uses "should", never "must". So what actually forces you to produce a survey? Three separate sources of compulsion, and they are easy to confuse:
- Local validation — your council's validation list requires arboricultural information where a proposal is on or near trees, or "likely to affect trees". If it's missing, the application is not validated — returned, unregistered, dead in the water.
- Planning conditions — permission is often granted subject to conditions requiring a final tree protection plan and arboricultural method statement before any work starts.
- Statutory protection — a Tree Preservation Order or conservation area, enforced by criminal law, sits on top of everything else.
A single tree can attract all three at once. Understanding which one you are up against is the difference between a smooth submission and months of delay.
The BS5837 report stack, in order
People say "a BS5837 survey" as if it were one document. It is really a stack of separate deliverables, produced at different stages. Knowing which you need — and when — is the single most useful thing on this page.
| Document | What it is | When it's produced |
|---|---|---|
| Tree Survey (with schedule) | A systematic record of every relevant tree: species, height, stem diameter, crown spread, age class, condition, BS5837 category and calculated RPA. | Before the design is fixed |
| Tree Constraints Plan (TCP) | A scaled drawing overlaying the survey onto the site — each tree's position, crown spread and RPA — showing the constraints before a layout exists. | Before the design is fixed |
| Arboricultural Impact Assessment (AIA) | Assesses the proposed layout against the trees: what's removed, what's retained, what conflicts arise. | Submitted with the application |
| Tree Protection Plan (TPP) | A drawing showing physical protection — barrier fencing, construction exclusion zones, ground protection. | With the application, finalised at discharge |
| Arboricultural Method Statement (AMS) | The "how": detailed methodology for any works near RPAs — no-dig construction, hand-digging, foundation design, supervision. | Often a pre-commencement condition |
| Site supervision / monitoring | On-site oversight during construction to prove the AMS and TPP are followed. | During construction |
The mental model that matters: the survey, TCP and AIA are the pre-permission "can we build this?" documents; the AMS, final TPP and supervision are the post-permission "prove you'll protect them" documents, discharged as conditions. The full arboricultural report family explains how they relate, and our guide to the five outputs of a BS5837 survey walks through each in detail.
The root protection area — the number that decides everything
The technical heart of every survey is the root protection area (RPA) — the below-ground rooting area that must be safeguarded from excavation, compaction and level change. The BS5837 formula is simple:
- RPA radius = 12 × the stem diameter, measured at 1.5m above ground.
- Capped at 707m² (a 15m radius) for very large trees.
- Veteran and ancient trees get an enhanced area — 15 × the stem diameter, or the canopy edge plus 5m, whichever is larger.
- Ancient woodland expects a minimum 15m buffer from the boundary.
A worked example: a tree with a 0.5m (500mm) stem diameter has an RPA radius of 12 × 0.5 = 6m (about 113m²). Try it on any tree with our RPA calculator and guide, and see whether you can build inside one when the layout leaves you no choice.
Tree categories: A, B, C and U
Every surveyed tree is graded into one retention category, which tells the case officer how hard the tree should be fought for.
| Category | Meaning | Expected remaining life |
|---|---|---|
| U | Unsuitable for retention — dead, dying or dangerously defective | Under ~10 years |
| A | High quality, worth retaining | 40+ years |
| B | Moderate quality, retention desirable | 20+ years |
| C | Low quality, little constraint | 10+ years (or young stems) |
A subcategory number records why a tree has value — 1 arboricultural, 2 landscape, 3 cultural/conservation — so an "A1" is a high-quality tree valued for its own arboricultural merit. One warning: some older, 2005-edition guides mention a "Category R". In BS5837:2012 the correct code is U — "Category R" is legacy and should not appear in a modern report. Our tree categories explained guide covers the full cascade chart.
What a tree survey costs
PlanWatch doesn't sell surveys, so here is the neutral going rate for 2026. The biggest variable is how many of the reports above your application actually needs.
| What you're buying | Typical 2026 price |
|---|---|
| Basic BS5837 survey (small domestic, a few trees) | ~£295–£760 |
| Survey + AIA (typical small development) | ~£500–£1,000 |
| Full planning package (survey + TCP + AIA + TPP + preliminary AMS) | ~£400–£1,500+ |
| Detailed AMS to discharge a condition | Additional fee on top |
| Large / complex site, many trees | £1,500 – several thousand |
The full breakdown, and the traps that make the cheapest quote the most expensive, are on our tree survey cost guide. Note that a BS5837 assessment can be done year-round — it doesn't need leaf cover — although any triggered ecology surveys (bats, nesting birds) have tight seasonal windows that can dominate the timeline.
Who is qualified to do the survey
There is no legal licence to be an arboriculturist and no statutory register you must appear on. BS5837 asks only that the work be done by someone "suitably qualified and experienced" — conventionally, a degree-level qualification (or N/SVQ Level 5) plus around three years' relevant recent experience. In practice a report from an Arboricultural Association Registered Consultant (AARC) or an Institute of Chartered Foresters (ICF) chartered arboriculturist carries the most weight and is the least likely to be challenged by a tree officer. Anyone can call themselves an "arborist"; the accreditations are the differentiator. Our find a tree surveyor page explains what to look for.
Requirements are set locally — check your council
Here is the point that governs everything above: the tree survey requirement is set locally, not nationally. There is no single statutory rule that says "a BS5837 survey is required." The obligation comes from each local planning authority's validation list, and those lists genuinely differ. What varies between councils:
- the exact trigger wording and any distance threshold for when a survey is needed;
- whether they demand a full AIA, TPP and AMS upfront or accept a survey only at validation;
- local TPO density and how much of the district is covered by conservation areas;
- the presence of ancient woodland or veteran trees, which raises the bar sharply;
- how strict the individual tree officer is in practice.
Councils publish their own guidance to prove the point — Guildford, Epsom & Ewell, Stockton-on-Tees, Bradford, West Lindsey and Welwyn Hatfield all have their own validation lists or standalone tree-survey guidance notes, and none is identical. So before you commission anything, read your own authority's local validation list and, ideally, ask the tree officer. Our guide to which LPAs require a tree survey explains how to find and read yours.
This is also where PlanWatch helps directly. Because PlanWatch tracks live planning data across 300+ local authorities, the area pages below show the real tree-related planning activity happening where you're building — applications affecting protected trees, arboricultural conditions being discharged, and refusals over tree impact. Explore a few examples in Leeds, Manchester, Lambeth, Bristol and Nottingham, or search your own postcode to see what's live in your area.
A note on nations: BS5837 is a UK-wide British Standard, but the statutory framework differs by nation. The detail on this site is England-centric (Town and Country Planning Act 1990 and the 2012 Tree Preservation Regulations). Scotland, Wales and Northern Ireland run parallel but distinct regimes — see TPOs in Scotland, Wales and Northern Ireland.
Where to start
- Not sure you even need one? Read do I need a tree survey for planning.
- Worried a tree is protected? Run a TPO check by postcode.
- Pricing a job? See the cost guide and what affects the price.
- Planning an extension or driveway? See tree surveys for home extensions and driveways.
Then use PlanWatch to watch live tree and planning activity around any UK address — including applications that affect protected trees near you.
