Croydon is one of South London’s most vibrant and diverse boroughs, with everything from Edwardian terraces in Addiscombe to modern family homes in Coulsdon. As property prices continue to rise, many homeowners are choosing to invest in extending their current homes rather than moving. Extensions are a smart way to gain extra living space and boost property value – but the first question that often comes up is: do you need planning permission?
At Suburban Group, with over 50 years of combined design and build experience, we’ve delivered countless extensions across Croydon and the wider South London area. Here’s a clear breakdown of what you need to know in 2025.
Permitted Development Rights in Croydon
The good news is that many house extensions fall under permitted development (PD) rights, meaning you don’t need to apply for full planning permission. In Croydon, this can apply to:
- Single-storey rear extensions – Up to 3 metres for a semi-detached/terraced home, or up to 4 metres for a detached property.
- Side extensions – Single storey only, and no more than half the width of the original house.
- Height restrictions – The extension must not exceed 4 metres in height, and it cannot be higher than the existing roofline.
- Materials – The build should use materials that are similar in appearance to the existing house.
For example, a small kitchen extension in South Croydon or Thornton Heath can often be carried out under PD rights, saving you weeks of planning delays.
When You’ll Need Planning Permission
There are plenty of situations, however, where planning permission will be required. These include:
- Two-storey extensions – Any extension adding a full extra floor will need approval.
- Extensions beyond PD limits – If you want to extend deeper into the garden or higher than PD allows.
- Conservation areas – Croydon has a number of conservation zones such as Norwood Grove and Addiscombe, where stricter controls apply.
- Flats and maisonettes – PD rights do not apply, so all works will need planning permission.
- Listed buildings – Croydon contains several listed properties, where special consent is needed.
How Long Does It Take?
If planning permission is required, Croydon Council typically takes 8–12 weeks to review and decide on applications. Larger or more complex projects may take longer, especially if objections are raised. This is why it’s important to get professional guidance before submitting plans.
Real-Life Example: Kitchen Extension in Purley
A recent Suburban Group project in Purley involved a family who wanted a 4.5-metre rear extension to create a spacious open-plan kitchen. Because the size exceeded permitted development limits, we handled the planning application on their behalf. The process took just under 10 weeks, and once approved, the build was completed in 16 weeks. The family gained a modern, light-filled living area and added an estimated £120,000 to their property value
Common Pitfalls Homeowners Face
Many Croydon homeowners underestimate how complex planning rules can be. Some of the most common mistakes include:
- Assuming PD applies – Not all properties qualify, especially flats and maisonettes.
- Overlooking conservation status – Areas like Central Croydon contain streets where stricter design rules apply.
- DIY submissions – Poorly prepared applications often get rejected, costing both time and money.
Why Work with a Design & Build Company?
Working with a specialist design & build firm like Suburban Group eliminates these headaches. We offer:
- Expert advice upfront – We confirm whether your plans fall under PD or need permission.
- Design that complies with Croydon regulations – Our architects prepare plans with local rules in mind.
- End-to-end management – From submitting applications to liaising with the council, we take care of everything.
- Transparency on costs – You’ll know exactly what to expect before work begins.
To Summarise
For many Croydon homeowners, extensions can be built under permitted development — but larger or more ambitious projects often require planning permission. The key is understanding which rules apply to your property before work starts.
At Suburban Group, we’ve spent years working with Croydon families to create extensions that are stylish, practical, and fully compliant. Whether you’re considering a kitchen extension in Purley, a two-storey build in Shirley, or a side extension in Addiscombe, our team will guide you through the process from start to finish.
Ready to explore your extension options in Croydon? Contact Suburban Group today to arrange a free consultation.
