When party wall works move into the higher-risk category—think basement construction, deep adjacent excavations, underpinning, or heavy structural alteration—the Act adds a powerful extra protection for neighbours: Security for Expenses.
Section 12(1) of the Party Wall etc. Act 1996 provides:
“An adjoining owner may serve a notice requiring the building owner before he begins any work in the exercise of the rights conferred by this Act to give such security as may be agreed between the owners or in the event of dispute determined in accordance with section 10.”
The crucial phrase is “to give such security.” In plain English: an adjoining owner can require a financial safeguard to cover foreseeable risks that could arise while the works are underway.
What Security for Expenses actually covers
Security is not a fine, fee, or upfront compensation. It’s a ring-fenced sum (or equivalent guarantee) set aside before work begins to deal with events such as:
- Damage to the adjoining owner’s property attributable to the notifiable works
- Emergency or safeguarding works to protect the adjoining owner’s property if the project stalls or a risk materialises (e.g., shoring an open trench, propping, temporary weathering)
- Professional fees reasonably and necessarily incurred in addressing those safeguarding measures (e.g., structural engineer input for an urgent make-safe)
If none of those events arise, the security is returned at the appropriate stage (see “Release & drawdown” below).
When Security is typically appropriate
Security is routinely considered where the risk profile is materially higher, for example:
- Basement construction and underpinning along a party wall
- Deep excavations (lightwells, piled foundations, contiguous/secan pile lines) close to the neighbour
- Complex temporary works or reliance on long, open excavations
- Projects with extended programmes or material insolvency risk indicators
For lower-risk Section 2 works (e.g., cutting pockets for beams with hand tools, modest chimney breast removal with suitable protections), security is less common—but it can still be requested and, if justified, awarded.
How the amount is assessed
If owners can’t agree the amount or form of security, the party wall surveyor(s) determine it under Section 10. The determination is based on reasonableness and foreseeable risk, commonly evidenced by:
- Engineer’s risk assessment (e.g., expected movement categories, method/sequence)
- Drawings & temporary works proposals (including excavation widths, durations, support methods)
- Scope & scale of potential safeguarding (e.g., propping, backfilling, temporary slabs, weathering)
- Likely costs (BCIS rates, contractor quotes, recent comparable awards)
Practical ranges: Residential security figures often sit in the £5,000–£50,000 bracket for typical basements/underpinning, but can be higher for complex works. The exact figure is case-specific.
Accepted forms of security
Surveyors will select a practical and reliable form, for example:
- Cash held by a stakeholder (commonly a solicitor’s client account)
- Escrow arrangement with agreed release conditions
Escrow arrangement is the most straightforward for small to mid-size projects.
Release & drawdown rules (what actually happens to the money)
Security is not paid away unless a qualifying event occurs. Awards will set clear conditions covering:
- Drawdown triggers – e.g., building owner’s default/insolvency; urgent safeguarding works; awarded damage not paid within the specified period
- Authorisation – usually the party wall surveyor(s) (or the third surveyor on referral) authorise any drawdown
- Partial release milestones – proportionate release as risk passes (e.g., after underpinning concrete achieves design strength; after backfilling; after structural sign-off)
- Final release – once the risk window has closed and any agreed making-good/cash settlement has been completed
Well-drafted awards stage the release so the sum isn’t tied up longer than necessary.
Timing: don’t leave it late
Security is a pre-condition: it must be in place before the building owner starts the relevant notifiable works. A sensible timeline:
- Early flag from the adjoining owner (or their surveyor) that security will be sought
- Evidence gathering (design pack, temporary works, sequence, programme)
- Quantum discussion and agreement—or referral to surveyors for determination
- Formalising the mechanism (stakeholder letter or guarantee wording) in the award
- Funds/guarantee lodged → works may commence
If the building owner refuses to give security that has been properly awarded, the surveyors can withhold the right to commence the relevant works until compliance.
How to keep Security proportionate (for both sides)
- Right-size the risk: let the engineer’s assessment lead quantum, not vague anxieties
- Narrow the draw window: align release stages to the actual construction sequence
- Be precise in the award: define triggers, authorisation, use of funds, and release points
- Communicate early: surprise security requests push programmes off-track needlessly
Key takeaways
- Section 12 empowers the adjoining owner to require Security for Expenses for higher-risk party wall works.
- If the amount/form can’t be agreed, the surveyor(s) determine it under Section 10.
- Security is ring-fenced, drawn only if needed, and released in stages as risk reduces.
- Well-prepared design and sequence information keeps security proportionate and programmes on track.
Need a clear Security for Expenses strategy?
Whether you’re requesting security or being asked to provide it, Simple Survey (RICS) will help you:
- Build a robust, evidence-led case for the right quantum and form,
- Draft tight award clauses (triggers, authorisation, staged release), and
- Keep your programme moving without compromising protection.
Email: team@simplesurvey.co.uk
Fixed fees. Nationwide coverage. RICS-qualified. Deep experience with basements, underpinning and complex temporary works.
Simple Survey — Fixed Nationwide Cost Chart (Guide)
| Service | What’s Included | Fixed Fee (incl. VAT) |
|---|---|---|
| Party Wall Notice (per Adjoining Owner) | Validity check, compliant drafting, service & tracking | £25 |
| Agreed Surveyor Award | One impartial surveyor acting for both owners | £300 |
| Building Owner’s Surveyor Award | Acting for Building Owner in a two-surveyor appointment | £300 |
Our fees are always fixed. We’re nationwide. We’re experienced and RICS-qualified.
FAQ
Q1: Can I demand security on any job?
A: You can request it, but surveyors will only award security where it’s justified by foreseeable risk. High-risk works (e.g., basements, deep excavations) are the usual candidates.
Q2: Who holds the money?
A: Commonly a solicitor’s client account (stakeholder). Alternatives include escrow or a bank guarantee. The award will set this out.
Q3: When do I get my money back (as the building owner)?
A: In stages as risk passes (e.g., after underpinning has cured and been backfilled) and finally once the project risks have ended and any damage issues are settled.
Q4: Can security be used for routine surveyor fees?
A: Security is generally meant for safeguarding works/damage events. The award will specify what drawdowns are permitted. Ordinary fee payments are usually handled separately via the award’s costs provisions.
Q5: What if the building owner won’t provide security that’s been awarded?
A: The right to commence the relevant notifiable works can be withheld until security is provided in the form and amount specified.
Want Section 12 handled calmly and correctly?
Email: team@simplesurvey.co.uk — we’ll put a proportionate, legally tight security plan in place.