How Much Does Building Control Cost

Building control is a legal requirement for most types of construction work in the UK, but the costs involved can vary widely depending on the type of project, the route you choose, and the complexity of the work. Whether you're applying through your local authority or using a private approved inspector, you’ll need to pay fees for both the application and the inspection process.

Understanding how building control charges are calculated can help you plan your project more accurately and avoid unexpected costs later on.

Factors That Influence Building Control Fees

The cost of building control depends on several key factors. The size and nature of the project are the most important. Small domestic works, such as removing an internal wall or installing a new bathroom, will cost significantly less than a two-storey extension or a new build.

Complexity is another major factor. If the work involves structural alterations, changes to drainage, or detailed fire safety measures, the level of inspection and assessment required increases — and so do the fees.

Different local authorities have their own charging structures, often based on national guidelines but with local adjustments. Private approved inspectors set their own fees, usually offering a custom quote based on your drawings and specifications. In some cases, their prices may be more competitive or flexible, especially for larger or commercial jobs.

The Cost of a Full Plans Application vs. a Building Notice

If you’re submitting a full plans application, you’ll typically pay a plan-checking fee up front, followed by a separate inspection fee once the work begins. The total cost is often split into these two parts, which reflect the admin and site visits involved.

A building notice application usually has one combined fee, as no formal plan checking is done in advance. While this route is simpler and faster, it’s only suitable for straightforward domestic work and doesn’t allow for early feedback on plans.

Although the upfront cost for a building notice might appear lower, unexpected issues uncovered during inspections can lead to delays or extra costs later on. In contrast, the full plans route provides greater certainty and can help avoid compliance problems during the build.

Typical Price Ranges

For small projects such as removing a non-load-bearing wall or converting a bathroom, building control fees might start from around £200 to £400. A single-storey extension typically costs between £400 and £900, depending on size. A loft conversion or garage conversion often falls into a similar range.

New builds or large, complex renovations can exceed £1,000 in fees, especially if they involve several inspections, engineering assessments, or specialist requirements like fire safety reports.

Private inspectors usually offer tailored quotes and may provide a more streamlined service for developers or repeat clients, but their prices can vary depending on location and demand.

Are There Additional Costs?

In most cases, the building control fee includes all necessary inspections and the final completion certificate. However, if the work deviates significantly from the original plan, or if re-inspections are required due to failed checks, additional charges may apply.

If you're applying for retrospective approval through a regularisation certificate, expect to pay more. These applications often cost more than standard ones because the inspector must assess completed work and may need access to hidden elements like wiring, insulation, or drainage.

VAT is usually added to all building control fees, so it’s important to factor that into your overall budget.

Why the Cost is Worth It

Although building control fees are an added cost, they’re essential for legal compliance, safety, and long-term property value. The certificate you receive at the end of the process proves that the work was completed to UK standards, and without it, you may struggle to sell or insure the property later.

By involving building control early, you reduce the risk of costly mistakes, non-compliance, or enforcement action. It’s a relatively small investment in the context of a larger building project and can save far more than it costs by avoiding serious issues down the line.

Price Transparency and Quoting

Unlike planning permission, building control fees are not fixed nationally. Each local authority publishes its own fee schedule, which is often available on its website. These charges are based on categories such as the floor area of the extension, number of dwellings, or the estimated cost of the work. Some councils offer calculators or downloadable tables to help you estimate the fee.

Private approved inspectors operate on a quote basis. They’ll usually ask for drawings and a project brief before issuing a tailored quote. The benefit here is often faster service, but some clients appreciate the transparency of fixed local authority charges.

In either case, you should always confirm whether the price includes VAT, re-inspections, and the completion certificate.

Residential vs. Commercial Costs

Fees for residential work are usually simpler and lower than for commercial or industrial developments. Commercial jobs may require more inspections, specialist input (e.g. fire engineers), or bespoke reporting, especially where large public spaces, high occupancy, or disabled access routes are involved.

For these reasons, commercial clients typically need a custom quotation regardless of whether they go through a local authority or an approved inspector.

Re-Inspection and Amendment Fees

If work fails an inspection and the inspector must return after corrections, a re-inspection fee may be charged — although this varies by provider. Similarly, if you make changes during the project that affect structure, drainage, or layout, you may need to submit revised drawings and pay an amendment fee.

Some authorities offer a grace period or waive minor re-inspection fees, but for major issues or repeat visits, extra costs can apply. It’s worth asking your inspector or council about their policy in advance.

Regularisation Charges

For unauthorised work — often discovered during a property sale — you can apply for a regularisation certificate. These fees are typically higher than standard building notice or full plans applications. That’s because the inspection is more difficult when work is already completed, and parts of the structure may need to be exposed.

Expect to pay a premium of 20–30% more for regularisation, and note that approval is not guaranteed. If the work fails to meet current regulations and can’t be altered, the certificate may be refused

Cost Saving Tips

Choosing the right application route can save money. If you’re confident in your builder and the job is straightforward, a building notice might be quicker and slightly cheaper. However, for larger or complex projects, the full plans route often prevents expensive issues during construction by highlighting compliance problems in advance.

Using a builder or contractor familiar with local building control processes can also reduce the risk of failed inspections and repeat charges. Some professionals have good working relationships with inspectors, which can help smooth out communication and scheduling.

Final Word

Building control costs vary, but they’re always a necessary part of doing construction or renovation work properly. Fees depend on the scope and complexity of your project, and whether you go through the local authority or a private inspector. Whichever route you take, make sure it’s built into your budget from the start — because without proper approval and certification, your project isn’t just incomplete, it could be legally vulnerable. Paying for building control isn't just about staying compliant — it’s about building safely and responsibly.