When it comes to improving your home, many people assume that every extension requires full planning permission. But here’s the good news: thanks to Permitted Development (PD) rights, that’s not always the case.

At Maydean Design, we help homeowners navigate the often confusing world of planning regulations — and one of the most common questions we hear is, “Can I extend without planning permission?” The answer is often yes, if you follow the rules.

What Are Permitted Development Rights?

Permitted Development rights are a set of national planning rules that allow homeowners to make certain changes to their property without having to submit a full planning application. These rights apply to many rear and side extensions, loft conversions, outbuildings, and more.

But there’s a catch: the rules are strict — and if you don’t meet all the criteria, you’ll need to apply for planning permission.

What You Can Typically Do Without Planning Permission

Under Permitted Development, you can usually:

• Build a single-storey rear extension up to 3m deep (4m for detached houses)
• Add a side extension that is no more than half the width of the original house
• Extend up to 8m at the rear (under the larger home extension scheme, subject to prior approval)

There are also height limits, material restrictions, and rules about boundary distances — so it’s vital to get the details right.

Important Exceptions

Permitted Development doesn’t apply everywhere. If your home is in a:

• Conservation Area
• National Park
• Area of Outstanding Natural Beauty
• Listed building

… then different rules apply, and you’ll almost certainly need planning permission.

Why You Should Still Apply for a Certificate of Lawfulness

Even if your project qualifies under Permitted Development, we always recommend applying for a Certificate of Lawfulness. It’s not mandatory, but it:

• Provides official confirmation that your extension is lawful
• Helps avoid issues when selling or remortgaging
• Offers peace of mind that you’ve done everything by the book

Let Maydean Design Handle It

Navigating planning rules can be stressful, but it doesn’t have to be. At Maydean Design, our expert team can:

• Assess your home and project against current Permitted Development rules
• Help you apply for a Certificate of Lawfulness
• Design your extension for both beauty and compliance

Book a free consultation today and let us help you unlock your home’s potential — with or without planning permission.