Corner plots and highway sightlines
A boundary fronting a road used by vehicles is limited to 1m under permitted development, but corner plots have a second constraint: the highway authority's visibility splay, which can require even lower boundary treatment near a junction so drivers can see pedestrians and oncoming traffic.
These splays are measured as a triangle from a set point back along both roads and are sometimes fixed by a planning condition on the original build rather than by the general permitted development rules.
A solid fence built to the letter of the 1m rule can still be a highway safety problem on a tight corner, so it's worth checking the local plan or asking planning before finalising height on a corner boundary.
Working around pets and children on site
An open trench, a stack of loose posts or a partially removed fence panel is an obvious hazard for a young child or an excitable dog, and on an occupied family garden it's worth agreeing at survey stage how pets will be kept away from the working area each day.
A garden with no boundary at all for part of a working day — because the old fence has come down and the new one isn't up yet — needs a temporary barrier or a clear arrangement for keeping animals indoors until the run is complete.
Leaving tools, concrete mix or offcuts accessible overnight on a site with children present is worth avoiding even where the work itself is finished for the day.
Listed building curtilage and garden structures
Listed building protection doesn't stop at the walls of the house — structures within its curtilage that were there at the date of listing, including some garden walls, gate piers and railings, can be treated as part of the listing itself.
That means a wall or gate that looks like an ordinary garden feature can technically need listed building consent for repair or replacement, and unauthorised work is a criminal offence rather than a simple planning breach.
Where a period boundary feature might be curtilage-listed, it's worth confirming with the council's conservation team before any demolition, since consent (or confirmation that it's not required) can usually be obtained in parallel with getting quotes.
Listed building curtilage and garden boundaries
Structures within the curtilage of a listed building — which can include garden walls, gate piers and sometimes fencing — may themselves be treated as part of the listing, even if not mentioned explicitly.
That means listed building consent can be required for work that would otherwise be unremarkable on a non-listed property, and doing work without consent where it's needed is a criminal offence.
Anyone unsure whether their boundary falls within this kind of curtilage should raise it with the council's conservation or listed buildings officer before starting.
Sequencing a multi-day install
A typical multi-day fence installation runs old fence removal and waste clearance first, then post setting with time for concrete to go off, then panels, gravel boards and capping once posts are firm enough to take a load.
Rushing panels onto posts before the concrete has cured enough — particularly in cold weather when curing slows down — is a common cause of a fence leaning within its first few weeks.
On a longer run it often makes sense to work in sections so part of the boundary is never left fully open overnight, rather than removing the entire old fence before any new posts are in.
Composite thermal expansion
Wood-plastic composite boards expand and contract with temperature considerably more than solid timber, since the polymer content responds more to heat than wood fibre does on its own.
Manufacturers specify a mandatory expansion gap at both board ends and between boards laid end to end, and skipping that gap during installation is one of the most common causes of composite decking or fencing buckling in hot weather.
Dark-coloured composite absorbs more solar heat than lighter shades and expands correspondingly more, so the expansion allowance recommended for a dark board is often greater than for a pale one of the same profile.
Raised beds built directly against a fence
A raised planting bed built with its back edge against a fence line keeps damp soil and mulch in permanent contact with the lowest boards or gravel board, which accelerates rot at exactly the point most vulnerable to moisture.
Lining the inside face of the bed against the fence with a damp-proof membrane, rather than backfilling soil directly onto the timber, reduces this contact without changing the visible design.
This detail is easy to miss at the planning stage since the bed and the fence are often specified and built by different trades without either flagging the interaction.
Boundary fencing near basement lightwells
Properties with a basement lightwell or sunken front area need fencing or railings around the opening itself for safety, independent of the main boundary treatment facing the street.
Post foundations for a fence running close to a lightwell need checking against the lightwell's own retaining structure, since digging a standard post hole too close to an unsupported excavation edge risks undermining it.
Drainage from a raised boundary or planting bed above a lightwell also needs directing away from the opening, since a fence that funnels rainwater toward a basement window is a bigger problem than the fence itself.
Reinforcing a hinge post weakened by gate movement
A gate hinge post takes repeated leverage every time the gate swings, which loosens its footing faster than a plain fence post nearby carrying no such load, and it's a common early failure point on a boundary that includes a gate.
Reinforcing usually means a larger post section, a deeper footing, or bracing back into the adjoining fence run, rather than simply resetting the same post size that already proved inadequate for the load.
Protecting an adjoining property while working a boundary corner
Work at a corner post often means standing tools, ladders or spoil temporarily on or very close to a neighbour's side of the boundary, which is worth agreeing in advance rather than assuming implied consent.
Where the corner adjoins a neighbour's planted border or a section of their own fence, photographing the condition before work starts gives both parties a clear reference if any question arises afterwards about pre-existing damage.
Finishing and clearing a corner section fully before moving along the rest of the run, rather than leaving it half-done for days, reduces the time any disruption to the neighbour's side is visible or ongoing.
Fencing shared or communal garden spaces
Communal gardens shared by several properties usually need any new fencing agreed by the group or managing body rather than one resident acting unilaterally, since a partition can change how the whole space is used.
Where a communal garden includes mature planting or trees under a collective management plan, new fence lines need checking against that plan rather than just against the ground itself.
Access routes for maintenance vehicles or refuse collection through a communal garden also need to stay clear when planning new subdivisions with fencing.
London Clay shrink-swell behaviour
London Clay is one of the most shrinkable soils in the country, expanding when saturated over winter and pulling away from anything set in it during a dry summer, sometimes opening a visible gap around a post base.
That cycle is what loosens posts that were adequately firm when first concreted in, rather than any fault in the original installation.
Depth and a granular key at the base do more to resist this movement long-term than simply increasing the volume of concrete around a shallow post.
Snagging and sign-off walk-round
A finished fence should be walked end to end with the client before sign-off, checking posts are plumb, panels are level and gates open and close cleanly through their full swing without binding on the ground.
Gaps under gravel boards, exposed fixings, and any concrete splashed onto adjoining paving or planting during the install are the kind of small snags worth catching at walk-round rather than left for the client to notice weeks later.
Where any item is flagged, agreeing a specific date for it to be resolved — rather than a vague 'we'll come back' — is what actually gets snagging closed out.
Checking existing boundary alignment before a like-for-like rebuild
Rebuilding a fence on the line of an existing one assumes that existing line was accurate, which isn't always the case — old fences can have drifted from the true boundary over successive repairs and replacements.
A quick check against any available reference, such as a boundary marker, an adjoining wall, or a neighbour's fence that's known to be accurate, is worth doing before assuming the old line should simply be copied.
Where a discrepancy is found, it's a conversation for the client and neighbour to have before rebuilding, since quietly correcting or quietly perpetuating a boundary error both carry consequences beyond the fencing job itself.
