Free tool · no sign-up Worked from the NHBC standard · ground read from the British Geological Survey
How close can a tree be to a house?
There is no legal minimum. What counts is the species, its mature height and whether you are on clay.
This will not tell you to fell anything. Most trees near most houses are fine, and taking out a mature tree can cause more damage than leaving it. It tells you whether yours is in the zone worth looking at.
Check your tree
Not sure counts as thirsty. That is what the standard says to assume.
Measure from the middle of the trunk to the nearest wall. Pace it out if you like, a stride is roughly three quarters of a metre.
Only used to draw the tree as it stands today next to the tree it will become. Capped at the mature height for the species. The verdict always uses the mature height.
We will read the actual geology under that postcode from the British Geological Survey. Or pick it yourself below.
What the numbers actually mean
The construction standard for building near trees works on a zone of influence: the distance out from the trunk where a tree can dry the ground enough to matter. It is worked out from the tree's mature height, not the height it is today, multiplied by how thirsty the species is.
- Thirsty species, 1.25 times mature height. Oak, willow, poplar, elm, hawthorn, leylandii.
- Middling species, 0.75 times. Ash, beech, sycamore, lime, most fruit trees.
- Thrifty species, 0.5 times. Birch, holly, hornbeam, hazel, magnolia.
That is why a birch and an oak at the same distance are not the same question. It is also why a tree that looks small now can still be inside the zone: the standard uses what it will grow into.
Why we will not tell you to fell it
When a tree that has been drying clay for decades comes out, the ground takes the water back and swells. That is heave, and the Association of British Insurers is blunt about it: the damage from heave is usually far more severe than the subsidence it was meant to prevent. Their guidance says trees older than the building should not be removed.
The better answer is nearly always management. A crown reduction on a sensible cycle cuts the leaf area, and the water the tree draws with it, without any of the risk of taking it out.
What this cannot tell you
- How deep your foundations go. That is the single biggest factor and you cannot see it from the surface.
- Whether the roots are actually under your footings. Only a trial pit shows that.
- Whether your soil is genuinely shrinkable. A geology map names the formation, not the plasticity of the clay in your garden.
- Whether existing cracks have anything to do with the tree. Leaking drains and building faults cause the same cracks.
- Whether the tree is protected. If it carries a TPO or sits in a conservation area, none of this matters until the council says yes. Check that first.
Trees near houses, answered
How close is too close to a house for a tree?
There is no legal minimum, so the honest answer is that it depends on the tree. The construction standard works on a zone of influence: the tree's mature height multiplied by how thirsty the species is. A thirsty tree like oak or willow gets 1.25 times its mature height, so a 20m oak screens at 25m. A thrifty one like birch gets half that.
What happens if a tree is too close to your house?
Usually nothing at all. On clay, a thirsty tree can dry the ground enough for it to shrink, and that is subsidence. It takes three things at once though: shrinkable clay, a thirsty tree within reach, and foundations shallow enough to sit in the drying zone. Most trees near most houses never cause any damage.
Is it safe to have a tree within 5 metres of my house?
For most small trees, yes. A hazel, magnolia or Japanese acer has a zone of influence under 5m, so it is not the question worth asking. An oak, willow or leylandii at 5m is worth a proper look, particularly on the Wadhurst Clay that runs through the High Weald.
How do I tell if a tree is too close to a house?
Identify the species first, because that sets everything else. Then measure from the middle of the trunk to the nearest wall, and find out whether you are on clay. The checker above does all three and reads the geology under your postcode from the British Geological Survey. What it cannot see is how deep your foundations go, and that is the single biggest factor.
Which trees should not be planted near houses?
The thirsty ones with height on them: oak, willow, poplar, elm, eucalyptus and leylandii. Hybrid black poplar reaches 28m, the widest zone of influence on our list. Planting distances are tighter than the figures for a tree already standing, on the reasoning that with a new tree you still have the choice.
What rights do I have if my neighbour's tree is too close to my house?
You can cut back roots or branches that cross the boundary, back to the line and no further, and the cuttings belong to your neighbour. You cannot go onto their land or top the tree. If it is a row of evergreens over 2m, the High Hedges part of the Anti-social Behaviour Act 2003 lets you ask the council to step in once you have tried to settle it directly.
Geology from the British Geological Survey. Contains British Geological Survey materials © UKRI 2026, and materials copyright NERC 2026, supplied under the Open Government Licence. BGS gives no warranty as to accuracy or fitness for purpose. A map tells you what is under the area. Only a hole in the ground tells you what is under your garden.
Want someone to actually look at it?
We survey trees near houses across East Sussex, and a good part of the High Weald sits on Wadhurst Clay, so this comes up a lot around Battle, Hastings and Crowborough. We will tell you honestly if the answer is leave it alone.