Do I need a party wall surveyor for a loft conversion?

Most loft conversions in Brighton and Hove do require party wall procedures, particularly on terraced properties. If you are inserting steel beams into party walls or altering the roof structure where it meets neighbouring properties, you will need to serve Party Wall Notices on affected neighbours before work begins.

What happens if my neighbour ignores the Party Wall Notice?

If your neighbour does not respond within fourteen days of receiving a Party Wall Notice, this counts as a deemed dissent under the Party Wall Act 1996. You then proceed with appointing surveyors to prepare a Party Wall Award. The work can still go ahead — a lack of response does not give your neighbour the right to stop your project.

Who pays for the party wall surveyor?

The building owner — the person carrying out the work — is responsible for all reasonable party wall surveyor fees. This includes your own surveyor's fees and, if separate surveyors are appointed, your neighbour's surveyor fees too. Agreeing on a single Agreed Surveyor to act for both parties is the most cost-effective approach.

How long does a party wall agreement take?

You should plan for 8 to 12 weeks from serving initial notices to being able to start work. The statutory notice period is two months for most party wall work, with an additional 4 to 6 weeks for surveyors to complete the schedule of condition and draft the Party Wall Award.

Can I do a rear extension without a party wall agreement?

If your extension is built entirely within your own boundaries and excavations do not come within the distances specified in the Party Wall Act, you may not need party wall procedures. However, given Brighton and Hove's typical terraced and semi-detached housing with narrow plots, many rear extensions do trigger the Act. A party wall surveyor can confirm whether your specific project requires notices.

Do I need a party wall surveyor for a rear extension in Brighton?

It depends on where the extension will be built relative to your boundary and your neighbour's foundations. Given Brighton's typical terraced and semi-detached housing stock with narrow plots, most rear extensions do require party wall procedures. GCC Sussex can assess your project and advise on whether notices need to be served.

What is Cost Planning in Construction? | GCC Sussex<br/>

What Cost Planning Actually Means

If you are planning a build or a significant development and you have started to think about budget, cost planning in construction is the process you need to understand first. Not budgeting in the general sense writing down a number and hoping contractors come in under it but a structured, stage-by-stage discipline that keeps the financial scope of a project under professional control from the earliest design concept through to the point where you go to tender.

A cost plan is a live document that evolves as the design develops. It starts with a high-level budget based on approximate floor areas and building type. It becomes progressively more detailed and more accurate as the architect's drawings become more detailed. By the time you are ready to appoint a contractor, a well-managed cost plan means you already know, within a workable margin, what the project should cost and where the risks sit.

Most construction projects that run significantly over budget do not do so because of bad luck in the build. They go wrong because the cost was never properly planned before it started. A cost plan is the tool that prevents that.

Cost Planning vs Estimating: What Is the Difference?

These two terms are often used interchangeably, but they describe different things and confusing them leads to gaps in financial control.An estimate prices a defined scope of work. You have a set of drawings, a specification, or a measured quantity, and an estimator calculates what it is likely to cost to carry that out. It is a point-in-time calculation based on a fixed input. GCC's estimating service covers exactly this: accurate, detailed pricing of a known scope.

Cost planning is different in kind, not just in scale. It is the active management of cost across the full design and pre-construction process. A cost planner does not just price the design as it is they track how cost moves as the design evolves, flag when a design decision is pushing the budget beyond what the project can bear, and model alternative options. Where an estimate is a snapshot, a cost plan is a running financial narrative of the project from inception to procurement.

To put it simply: you need an estimate to price what you have decided to build. You need a cost plan to make sure that what you decide to build is something you can afford.

When Cost Planning Happens: The Design Stages

Cost planning maps closely to the RIBA Plan of Work, the industry-standard framework that structures the stages of a construction project from initial brief through to completion. Understanding how cost planning fits into those stages helps clarify why starting early makes such a difference.

Stage 1 to 2: Strategic Definition and Preparation

This is the earliest budget: an order-of-magnitude figure based on the type of building, the approximate area, and current market rates. At this stage there is no detailed design to price, so the cost plan uses cost-per-square-metre benchmarks derived from comparable projects and current data, BCIS and SPONS data, alongside a firm's own database of recent work. The purpose is to test whether the project is financially viable before significant design fees are committed.

Stage 3: Spatial Coordination (Elemental Cost Plan)

As the architect develops the design, the cost plan becomes elemental meaning it breaks the project down by building element (substructure, frame, envelope, internal finishes, services, and so on) and costs each element separately. This elemental cost plan is more granular and more accurate than the initial budget, and it allows the design team to see exactly where cost is concentrated and where it might be reduced if needed.

Stage 4: Technical Design (Pre-Tender Estimate)

By the time the design is sufficiently complete to go to tender, the cost plan has evolved into a pre-tender estimate: a detailed, closely costed document that sets a reliable benchmark against which contractor bids can be assessed. If the pre-tender estimate and the contractor's bid are broadly aligned, you have confidence in the tender figure. If they diverge significantly, that is a signal to investigate rather than simply accepting the lowest price.

The key point across all three stages is continuity. The cost plan that starts as a broad budget should, if managed properly, develop into the pre-tender estimate without any sudden surprises. Cost certainty at tender does not come from luck, it comes from careful management at every stage before it.

What Goes Into a Cost Plan

A cost plan is not just a build cost figure. A properly prepared cost plan covers every financial component of delivering the project:

Measured works. The core construction costs -- structure, envelope, fit-out, services -- calculated by element based on quantities and current market rates.
Preliminaries. The contractor's site-level costs that are not tied to specific work packages: site setup, welfare, management, plant, and programme-related costs. These typically add 10 to 15 percent to the measured works figure and are commonly underestimated by those without QS experience.
Contingency. A percentage held against design risk (things not yet fully resolved in the design) and construction risk (unforeseen site conditions or variations). The appropriate level depends on the project stage and complexity -- a contingency set too low is not a saving, it is an optimistic assumption waiting to fail.
Professional fees. Architect, structural engineer, mechanical and electrical engineer, planning fees, building control, and the cost consultant's own fees. These are part of the total project cost and should be included in the plan from the outset.
Inflation allowance. On projects with a programme stretching beyond six months, construction cost inflation needs to be built into the plan. Leaving it out creates a structural gap between the cost plan and the outturn cost, particularly in a market where material and labour costs remain volatile.
VAT and other statutory costs. Depending on the project type and end use, VAT treatment varies significantly. It is not always 20 percent and the implications for total project cost need to be clear from early in the planning stage.

Receiving a cost plan that covers all of these components -- not just the build cost -- is the difference between knowing what your project will cost and knowing only part of it.

How Cost Planning Protects Your Budget

The financial value of cost planning is most obvious in what it prevents. Projects that overspend typically do so at one of three points: when an unrealistic early budget is set and never properly challenged; when design decisions are made without understanding their cost implications; or when the tender figure arrives and is materially higher than anyone expected.

A managed cost plan closes all three gaps.

Setting a realistic early budget -- one grounded in current market data rather than aspiration -- means you enter the design process with a financially viable brief. When design decisions are made with a cost planner in the room, the team knows immediately whether a structural choice, a specification upgrade, or a change in procurement route has a cost consequence that fits within the budget or requires a trade-off elsewhere. And because the pre-tender estimate is developed progressively from that early budget rather than produced for the first time at the end of the design stage, the tender figure rarely comes as a shock.

Value engineering -- the process of finding cost savings without reducing quality or functionality -- is also most effective early. A cost planner can identify where the design is carrying unnecessary cost and model alternatives while the design is still fluid. Once a project is on site, the same changes cost significantly more to implement.

Put bluntly: the cost of good cost planning is small relative to the cost of the mistakes it prevents.

Cost Planning for Commercial and Development Projects in Sussex

The Sussex construction market has its own characteristics that affect how a cost plan needs to be structured. Labour costs across Brighton, Hove, and the wider coastal belt reflect proximity to London and a smaller local contractor base than a larger city would have. Material costs are broadly in line with national benchmarks but with regional supply chain patterns that an experienced local consultant will know. Heritage and conservation constraints on a significant proportion of Sussex's building stock add design and specification cost that a national cost plan template will not capture.

For developers working on residential schemes in Brighton and Hove, planning consent conditions, shared ownership requirements, and S106 obligations all have cost implications that need to be modelled as part of the plan. For commercial landlords managing refurbishments or fit-outs, phased occupancy and tenant specification requirements add complexity that a simple build cost estimate will not address.

GCC Sussex's quantity surveying and cost management service is built around these realities. We use BCIS and SPONS market data alongside our own database of active and recently completed Sussex projects to produce cost plans that reflect what things actually cost to build here, not national averages applied to a local context.

Working With a Chartered Cost Consultant

A cost plan is only as useful as the professional preparing it. RICS accreditation matters here because it sets the minimum standard for how cost information is prepared, presented, and stands up to scrutiny -- from funders, planning authorities, or other professionals on the project team.

GCC Sussex are RICS-accredited chartered surveyors with more than 20 years of experience across residential, commercial, and development projects in Sussex. Our approach to cost planning is straightforward: we get involved early, we update the plan as the design develops, and we tell clients what the numbers mean rather than just presenting them.

Cost planning works best when the cost consultant is part of the design team from the start, not brought in to check a design that has already been fully developed. If you are in the early stages of a project -- whether that is a residential development, a commercial building, or a significant self-build -- the right point to start is now.

Frequently Asked Questions

Cost planning fees are typically calculated as a percentage of the construction cost, or agreed as a fixed fee for a defined scope of work. The percentage varies depending on project size and complexity, larger and more straightforward projects tend to attract a lower percentage than smaller or highly technical ones. GCC Sussex provides a clear fee indication once you have outlined your project. The cost of professional cost planning is consistently small relative to the cost of the overruns it prevents. Get in touch to discuss fees for your project.
As early as possible, ideally at the point when you have a project brief and some initial design thinking, before the architect has committed to a scheme in any detail. The earlier a cost consultant is involved, the more influence they can have on the financial outcome. Bringing in a cost planner after the design is complete is better than not having one at all, but the opportunity to shape cost has largely passed by that point.
No. A contractor's quote is that contractor's price for carrying out a defined scope of work, based on their own costs, margins, and commercial judgement at a point in time. A cost plan is an independent professional assessment of what the project should cost, produced before a contractor is appointed and used to set a benchmark against which tender bids are evaluated. They serve different purposes: the cost plan tells you what you should expect to pay; the contractor's quote tells you what one contractor is willing to do it for.
Most residential extensions and smaller renovations do not require a formal multi-stage cost plan in the way that a development or commercial project would. However, even for smaller projects, having an independent pre-tender estimate, a professional view of what the work should cost before you go out to contractors is genuinely useful. It tells you whether the quotes you receive are reasonable and gives you a basis to challenge any that seem out of step. GCC's estimating service is tailored to exactly this kind of project.