Construction Permits in the UK – What You Need to Know

If you’re planning a conservatory, garden room or any house extension, the first question is usually: do I need a permit? The short answer is yes, most projects need some form of approval from your local council. Ignoring this step can lead to fines, forced removal, or costly delays. Below we break down the basics, so you can start your build with confidence.

When a Permit Is Required

In the UK, the two main approvals are Planning Permission and Building Regulations consent. Planning permission looks at the look of the project – height, impact on neighbours, and whether it fits the area’s character. Building Regulations focus on safety – structural integrity, fire safety, energy efficiency and accessibility.

Most small conservatories fall under Permitted Development rules, meaning you can skip full planning permission if you stay within size and height limits (usually 4 metres high for a rear extension and a total floor area not exceeding 50% of your home’s existing floor space). However, you’ll still need Building Regulations approval, and you must check any listed building or conservation area restrictions.

How to Apply – A Simple Step‑by‑Step

1. Check Permitted Development limits on the Planning Portal or your council’s website. If your project exceeds those limits, you’ll need full planning permission.

2. Gather documents: site plan, drawings, elevations, and a design and access statement if required. For Building Regulations, you’ll need structural calculations and details about insulation, ventilation and fire safety.

3. Submit the application online via the Planning Portal. Most councils charge a modest fee (around £100‑£500 depending on the scope).

4. Wait for a decision. Planning permission typically takes 8‑12 weeks. Building Regulations can be approved within 2‑4 weeks if your paperwork is complete.

5. Arrange inspections. After work starts, a building control officer will visit to check foundations, walls and final completion.

Getting these steps right the first time saves you from having to redo work or face enforcement notices later.

Pro tip: Talk to your local council before you draw up plans. A quick phone call can clarify if your project needs planning permission, and they may point out common mistakes that cause rejections.

Another common snag is overlooking neighbour objections. Even if you meet all the technical limits, a neighbour who feels the new structure blocks their view or reduces light can trigger a formal objection, extending the decision time. A friendly chat and a simple visual mock‑up can often smooth things over.

Cost-wise, expect to pay around £500‑£1,500 for building control inspections and any required structural engineer reports. If you hire a professional designer or architect, their fees will add to the budget, but they can also speed up the approval process by producing council‑ready drawings.

Remember, a rejected application isn’t the end. You can usually amend the plans and resubmit. The key is to address the council’s feedback directly – whether it’s reducing the height, changing the materials or adding a mitigation measure for drainage.

Finally, keep all approval documents on site. If you ever sell the house, buyers (and their mortgage lenders) will ask for proof that the extension was legal. Having the paperwork ready prevents last‑minute headaches.

Whether you’re adding a sun‑filled conservatory, expanding your kitchen or building a new garden office, getting the right construction permits is the foundation of a smooth project. Follow the steps, stay in touch with your council, and you’ll turn your home improvement ideas into reality without unnecessary roadblocks.