Building a Deck or Pergola Near Protected Trees in Christchurch

Can I build a deck or pergola near a protected tree?

Sometimes, but not without the council's say-so if the work touches the tree. The government's tree guidance lists cutting down, topping, lopping, uprooting, wilful damage and wilful destruction as things a Tree Preservation Order (TPO) forbids without consent, and says that in the Secretary of State's view "cutting roots is also a prohibited activity and requires the authority's consent".

Permitted development doesn't get you round this. The same guidance says consent is still required for work on a protected tree "that is necessary to implement permitted development rights". So a deck that needs no planning permission can still need tree consent.

How do I check if a tree is protected?

There are two ways a tree can be protected:

• A Tree Preservation Order. BCP Council has a map of protected trees in Bournemouth, Christchurch and Poole.
• A conservation area. Trees in a conservation area are protected even without a TPO. In Christchurch, BCP's list includes Christchurch Central, Mudeford Quay, Stanpit and Fisherman's Bank, Purewell, Burton, Winkton and others.

For a conservation-area tree without a TPO, the government guidance asks for six weeks' written notice to the council before work. That applies to trees over 75mm across, measured over the bark 1.5 metres above the ground.

What happens if roots get cut without consent?

BCP Council says unauthorised work on protected trees "is a criminal offence that may lead to prosecution", and the government guidance says serious cases can go to the Crown Court with an unlimited fine. The tree can't be put back either. The honest route is to ask first.

Asking isn't expensive. BCP says its standard eight-week application for TPO work is free (BCP Council).

How can a deck be built near tree roots?

The usual approach is to disturb as little ground as possible. Fewer, smaller footings, placed by hand where a test dig finds no large roots, with the frame raised to span over the root area rather than a trench or a slab across it. Ground screws can help here, because they need no digging out.

Whether that's acceptable for a protected tree is the council's decision, so the plan goes in the application. For a big or valuable tree, an arborist's advice on where the roots run is worth having before the design is fixed.

What about shade, damp and leaf fall?

Under trees, a deck stays damp for longer and collects leaves. The frame should be timber treated for ground contact: the Wood Protection Association's buyer’s guide puts decking posts, joists and sub-structures in Use Class 4. For the boards, I cover grip and algae in slippery and shaded decking.

Do I also need planning permission?

Tree consent and planning permission are separate. Most low decks and pergolas at a house don't need planning permission, but Christchurch has several conservation areas where the side of the house is restricted. See my guides to decking planning permission and pergola planning permission.

Before anyone digs near a tree:

• Check the TPO map for a protected tree.
• Check the conservation area list for your address.
• Apply or give notice first, and wait for the answer before work starts.
• Ask how the footings avoid the roots, and get it written on the quote.

Where these rules come from: GOV.UK, Tree Preservation Orders and trees in conservation areas · BCP Council, Tree Preservation Orders · BCP Council, conservation areas · Wood Protection Association, Buyer's Guide to Preservative Treated Wood (Issue 4, 2020). Checked October 2026. Rules change, so treat this as a guide and check your own address with BCP Council before you build.

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