If your development affects trees, you generally need a tree survey and Tree Constraints Plan first, an Arboricultural Impact Assessment (usually with a Tree Protection Plan) to submit with the planning application, and an Arboricultural Method Statement plus finalised TPP later to discharge conditions — but which apply depends on your stage and your local authority's validation list.
The four acronyms — AIA, AMS, TPP and TCP — describe distinct deliverables that come out of a BS5837:2012 tree survey. They are not interchangeable, and applicants routinely commission the wrong one, or all of them unnecessarily. This page gives you the decision matrix competitors rarely publish clearly.
The four documents at a glance
| Acronym | Full name | What it is | Typical stage |
|---|---|---|---|
| TCP | Tree Constraints Plan | A scaled drawing overlaying survey data — tree positions, crown spread, root protection areas and shade — onto the site before a layout exists | Pre-design |
| AIA | Arboricultural Impact Assessment | A report assessing the proposed layout against the trees: what's removed, what's retained, what conflicts arise | Submitted with the application |
| TPP | Tree Protection Plan | A scaled drawing showing physical protection — barrier fencing, exclusion zones, ground protection | With the application and/or at discharge |
| AMS | Arboricultural Method Statement | The detailed methodology for working near retained trees — no-dig construction, foundation design, supervision, phasing | Often a pre-commencement condition |
The key mental model: pre- vs post-permission
The single most useful way to understand these documents is by when they do their work.
The survey, TCP and AIA are the pre-permission "can we build this?" documents. They exist to shape the design and get the application validated and determined. The AIA is where the proposed layout meets reality: it identifies which trees must go, which are retained, and where roads, foundations, drainage or level changes conflict with a root protection area.
The AMS and finalised TPP are the post-permission "prove you'll protect them" documents. An AMS is very often imposed as a pre-commencement condition — meaning no site works may lawfully begin, even with full planning permission, until the authority approves it in writing. Starting before that condition is discharged can render the whole development unlawful and expose you to enforcement.
Getting this sequence wrong is expensive, so it's worth internalising before you commission anything.
The decision matrix
Work through these questions in order.
1. Have you designed the layout yet?
No → You need a tree survey and a TCP first. This is the correct starting point and the one applicants most often skip. BS5837 is design-led: the survey should inform the layout, not be bolted on afterwards. A TCP shows you the developable envelope once you subtract RPAs and shade, so you design around real constraints instead of discovering them later.
Yes → Move on — but be aware that if the layout was fixed without arboricultural input, the AIA may force a redesign.
2. Are you submitting a planning application that affects trees?
Yes → You need an AIA, and almost always a TPP alongside it. Most local validation lists require arboricultural information where there are trees on, overhanging or near the site, or where the work will impact trees — explicitly including driveways, patios, drainage and utility runs, and neighbouring trees whose RPAs cross the boundary. Without these documents the application may not even be validated.
3. Has permission been granted with a tree condition?
Yes → You need a detailed AMS and a finalised TPP to discharge that condition. Read the condition wording carefully: a pre-commencement condition bars all site works — including demolition, clearance and bringing machinery on — until the authority approves the AMS in writing. The LPA has a target period, commonly around eight weeks, to respond to a discharge application.
4. Does the condition require monitoring?
Sometimes → Tree conditions frequently also require arboricultural site supervision during construction, with visit records or certificates confirming the TPP and AMS were followed. That's a service rather than a document, but budget for it — it's a genuine planning obligation, not an optional extra.
A worked example: rear extension near a neighbour's oak
Say you want a single-storey rear extension, and next door's mature oak sits three metres beyond the boundary with an RPA that reaches several metres into your garden. Sequence it right and it's straightforward: a survey + TCP show the RPA footprint before you draw anything; you design the extension to sit clear of it (or specify no-dig construction where a corner clips it); an AIA + TPP go in with the application demonstrating the oak is retained and protected; and after permission, a detailed AMS discharges the pre-commencement condition, specifying fencing lines, hand-digging near roots and supervision. Sequence it wrong — design first, survey last — and the AIA reveals your footings run straight through the RPA, forcing a redesign or a refusal.
Common mistakes this matrix prevents
- Commissioning an AMS too early. A detailed method statement written before the layout is fixed is wasted effort; it belongs at the discharge stage, once the design is settled.
- Submitting an AIA with no TCP behind it. If nobody plotted the constraints first, the AIA often reveals conflicts that force redesign and delay.
- Assuming the application documents cover the conditions. A draft or preliminary AMS submitted with the application usually still has to be re-submitted in detailed form to discharge the condition.
- Ignoring neighbouring trees. Off-site trees whose RPAs extend into your site must be surveyed and assessed — you don't have to own a tree for it to constrain your build.
- Confusing the TCP and the TPP. Constraints plan comes first and is about where you can build; protection plan comes later and is about keeping retained trees safe on site.
Which do you actually need?
For a typical small development affecting trees, the realistic package is: survey + TCP (early), then AIA + TPP (with the application), then detailed AMS + finalised TPP (to discharge conditions). A simple householder scheme touching one or two trees may need far less; a large or phased site materially more, often with staged AMS submissions per phase. For a fuller breakdown of each deliverable and how they nest together, see our guide to the arboricultural report.
Which documents you need is set locally — check your authority
Here's the part no generic explainer can settle for you: exactly which of these documents an authority demands, and at what stage, is set locally by each local planning authority. Some councils want a full AIA + TPP + preliminary AMS upfront; others accept a survey and AIA at validation and condition the rest. Local TPO density, conservation-area coverage and the presence of ancient or veteran trees all change how much detail a tree officer expects, and how hard they push back. There is a national validation baseline, but the arboricultural specifics are a local overlay — which is exactly why applicants get caught out generalising from another council's requirements.
So confirm your authority's validation list before commissioning anything. PlanWatch tracks live planning and tree-related activity down to the individual local authority, so you can see how your council is treating tree matters right now. Explore example authorities such as Leeds, Manchester or Bristol, or start from the tree-surveys hub and find yours. Our guide to which LPAs require a tree survey collects documented examples.
Note: this guidance is England-centric. BS5837:2012 applies UK-wide as a British Standard, but the statutory planning framework — and the tree-protection consent rules that sit alongside it — differ in Scotland, Wales and Northern Ireland. When you're ready to commission, our page on finding a tree surveyor covers what to look for.