Practical points for boundary work in Bush Hill Park
Surface-water run-off across a boundary
Where one garden sits higher than its neighbour, or has a hard surface that sheds rain quickly, surface water often crosses the boundary line rather than staying on the plot it fell on.
A solid close-boarded fence with gravel boards set into the ground can act as an unintended dam, backing water up against the base and accelerating rot in the boards nearest the high side.
A small gap under the boards, or a French drain running parallel to the fence line, lets water pass through without saturating the timber, and is worth raising with a client before installation rather than after a wet winter.
Equestrian and paddock fencing basics
Post-and-rail is the standard equestrian boundary because it's forgiving on impact — a horse pushing against it is less likely to be injured than against wire or a rigid panel, and any wire used alongside timber rails needs to be clearly visible, not fine-gauge stock wire that a horse can't see.
Field gate widths for equestrian use are wider than a domestic garden gate, usually at least 3.6m, to allow a horse to be led through without crowding the gateposts.
Paddock fence lines also need checking for toxic hedge or tree species growing along the boundary, since horses can reach through post-and-rail in a way they can't through a solid fence.
Outbuildings close to a boundary and separate rules
Garden rooms, sheds and other outbuildings have their own distinct permitted development rules on height and proximity to a boundary, which are different from the rules governing fences, walls and gates.
It's a common mix-up to apply fence height limits to an outbuilding, or vice versa, when checking what's allowed near a boundary line.
Where a fence and a new outbuilding are being planned together near the same boundary, it's worth checking each against its own specific permitted development category.
Retrospective applications and planning appeals
A retrospective planning application can be made for work already carried out without permission, and is assessed against exactly the same policies as if it had been applied for in advance, so there's no guarantee of a more lenient outcome simply because the fence already exists.
If a retrospective application or an enforcement notice is refused or unfavourable, there's a right of appeal to the Planning Inspectorate, but appeals take months to determine and the structure may need to remain unchanged or be altered in the meantime depending on the notice.
It's worth noting that a refused retrospective application still leaves the underlying breach live, so appealing or reapplying with a revised, compliant design is often quicker than contesting the principle of refusal.
Setting out a straight run with string lines
A straight fence line starts with two fixed end points and a string line pulled taut between them, usually run just above where the posts will sit rather than at ground level where it snags on grass or debris.
On a long run the string sags under its own weight, so an intermediate profile or peg is needed every few bays to keep the sight line true rather than trusting a single span.
Any post that's set even 10-15mm off that line becomes visible once panels go in, because the eye picks up a wander in a boundary far more readily than a small step in level.
Arris rail mortice joint wear
A traditional arris-rail panel fence uses a triangular-section rail slotted into a mortice cut through the post, and repeated wind loading can gradually enlarge that mortice, letting the rail rock and eventually loosen the whole panel.
A mortice cut slightly oversized from the start, or one that's been enlarged by rot before a replacement rail is fitted, is a common weak point that arris-rail brackets were largely developed to bypass.
Galvanised metal arris-rail brackets, fixed to the face of the post rather than through it, avoid weakening the post with a mortice at all and are now the more common detail on new panel fencing.
