Shoring a party wall during conversion works
Temporary support to a party wall is notifiable work under section 2 of the Party Wall etc. Act 1996. The notice periods, the award and the condition survey all sit outside planning, and they drive the programme.
Cutting a new opening through a party wall, taking out a chimney breast or dropping a floor level during a flat conversion all need the wall above held up while you work. That temporary support is where the Party Wall etc. Act 1996 bites hardest, because needling and propping a party structure is a notifiable work under section 2 and it usually triggers a two-month notice period before a tool is lifted. Planning permission has nothing to say about it. Neither does your building control approval, which deals with the permanent structure rather than how you get there.
The sequence that goes wrong is familiar. Permission granted in March, contractor on site in April, notice served in April, neighbour appoints a surveyor in May, award in June. Two months of preliminaries paid for nothing.
When temporary support becomes necessary
Any time you remove load-bearing fabric from a party structure, something has to carry the load it was carrying. In conversion work that means four recurring situations: forming an opening for a new doorway or a knock-through, removing a chimney breast where the stack continues above, inserting a beam to carry a floor that was previously supported off the party wall, and lowering a ground floor slab next to a shallow party wall footing.
The last one is the awkward case. Lowering a floor to gain head height in a lower ground floor flat often exposes the underside of the party wall foundation, which puts you into section 6 excavation territory as well as section 2.
Shoring is also used defensively. Where a neighbouring building is in poor condition, a surveyor may require support before you touch anything, and the cost of that falls on the party carrying out the works under section 11 in most configurations.
Needling, propping and flying shores
Needling is the standard method for opening up a wall. Short beams, the needles, are passed through holes cut in the wall above the proposed opening and supported on props or a frame on both sides, so the wall above transfers its load to the props while the masonry below is removed and the permanent beam set in place. Done properly it is unremarkable. Done with props standing on an unverified slab, it is how floors get punched through.
Dead shores carry vertical load down to a sound bearing, usually through sole plates spreading the load across a slab or onto a temporary foundation. Raking shores lean against a facade and take lateral load into the ground outside, which needs land you have a right to occupy. Flying shores span horizontally between two buildings and prop both, which makes them the option of choice in a narrow terrace where there is no space outside for a rake. Where the support or the lifting operation reaches beyond your boundary you are in the same territory as crane oversailing third party land, and you need a right to be there.
Each of those needs a load path drawn on paper. The common failure is not the shore itself but the thing it bears on: a suspended timber floor, a vault, a drain run or a slab whose thickness nobody checked.
Notices the works trigger
The Act sets two notice regimes and they run on different clocks.
| Work | Section | Notice period | Served on |
|---|---|---|---|
| Cutting into, raising, underpinning or needling a party structure | Section 2, notice under section 3 | Two months | Each adjoining owner |
| Excavation within 3 metres and below the level of a neighbour's foundations | Section 6(1) | One month | Each adjoining owner |
| Excavation within 6 metres cutting a plane at 45 degrees from the foundation | Section 6(2) | One month | Each adjoining owner |
| Building a new wall at the line of junction | Section 1 | One month | Each adjoining owner |
An adjoining owner has 14 days to consent or dissent to a party structure notice. Silence counts as dissent, which is what normally happens, and a dispute is then deemed to have arisen under section 10. Each side appoints a surveyor, or both agree an agreed surveyor, and the surveyors make an award covering the works, the method, the hours, access and the condition record.
The excavation notices catch more conversion schemes than owners expect. A new lift pit, a soakaway, a pile cap or a deepened footing to a bay all sit below neighbouring footings at terraced-house scale.
Condition surveys before and after
A schedule of condition is not a statutory requirement, but no competent surveyor will make an award without one. It is a room-by-room written and photographed record of the adjoining property before works start, and it is the only document that resolves the inevitable argument about whether a crack over a door was there in advance.
Get access early. The adjoining owner is under no obligation to let anyone in before the award is served, and a refused inspection pushes the whole programme back. Where access is refused outright, surveyors will usually proceed on an external inspection and record the limitation, which leaves you in a weaker position on any later damage claim.
A post-works inspection against the same schedule closes the file. Investors who skip it carry an open-ended exposure into the sale.
Design responsibility for the temporary scheme
Temporary works design is a designer duty under the Construction (Design and Management) Regulations 2015, and on anything beyond a single lintel it belongs with a structural engineer rather than with the contractor's site manager. The industry practice is a temporary works register, a design brief, a check at a category proportionate to the risk, and a named temporary works coordinator who releases each stage.
Where a council has conditioned a method statement, as it often does on basement and larger conversion schemes, the temporary works philosophy is usually what the condition is reaching for. The same discipline governs protection of anything else that cannot be moved, which is why temporary works and tree protection on tight sites tend to be designed together. A Structural Survey that records existing construction, wall thicknesses and foundation depths gives the engineer something to design from, and councils generally expect a suitably qualified author for that kind of report.
One honest uncertainty: the line between what a party wall award controls and what a planning condition controls is blurred in practice, and different authorities take different views on how much structural detail they want at application stage. Ask the case officer rather than guess.
Insurance and security for expenses
Three covers matter on a shored conversion. The contractor's public liability, which responds to negligence. Non-negligent liability cover for damage caused by the works where nobody was careless, which is the policy most often missing. And buildings insurance on both properties, which the award will usually require you to notify.
Section 12 lets an adjoining owner request security for expenses before notifiable works start. In practice it is requested on basement schemes and on works by single-purpose vehicles with no balance sheet, and it is satisfied by a deposit held jointly or by a bond. Budget for it on any scheme where you are the building owner and the neighbour is advised.
Where temporary support is needed because of the adjoining building's own condition, section 11 apportionment can put part of the cost on the neighbour. That argument is run by surveyors, not by owners, and it rarely moves far.
Sequencing against the main programme
- Survey the existing structure and record foundation depths and wall construction before you fix the design.
- Commission the temporary works design, so the notice can describe the actual method rather than an intention.
- Serve the section 3 and section 6 notices together where both apply, and date them from the later of the two periods.
- Allow 14 days for a response, then a surveyor appointment and an award. Four to ten weeks from notice to award is a reasonable planning assumption.
- Carry out the schedule of condition under the award.
- Start the works, observing the agreed hours and the access arrangements under section 8.
The one change that saves the most time is serving notice before the contractor is appointed rather than after. Nobody enjoys paying prelims to wait for a neighbour's surveyor. And the award will often tighten working hours in a way that affects your build programme, which is far easier to price before the contract is signed.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. If you want a view on which supporting documents your conversion is likely to need, enter your postcode on PlanScope and work through the guided questions.
PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
Does needling a party wall need a party wall notice?
Yes. Cutting into a party structure and inserting needles to support the wall above falls within the works listed in section 2 of the Party Wall etc. Act 1996, so a party structure notice under section 3 is required. That notice carries a two-month period, which runs whether or not the adjoining owner engages with it.
How long does it take to get a party wall award?
Allow four to ten weeks from service of notice to a signed award on a straightforward conversion. The adjoining owner has 14 days to respond, dissent is deemed if they do not, surveyors are then appointed and they need time to inspect, agree the method and prepare the condition schedule. Basement schemes commonly take longer.
Do I need planning permission for shoring?
Temporary support to your own building is not normally development in its own right, so it does not usually need permission. The conversion it enables will often need permission, and a council may condition a structural method statement. Building regulations approval deals with the permanent structure rather than the temporary works that get you there.
Who designs the temporary works?
A structural engineer, acting as a designer under the Construction (Design and Management) Regulations 2015, on anything beyond a single lintel. Industry practice adds a temporary works register, a design brief, an independent check proportionate to the risk and a named coordinator who signs off each stage before loads are transferred.
What is security for expenses?
Section 12 of the 1996 Act lets an adjoining owner ask you to secure the cost of making good before notifiable works start. It is usually met by a sum held jointly by the two surveyors or by a bond. Expect it to be requested on basement works and where the building owner is a company with no assets.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.