What to Consider Before You Buy: Can You Extend Your New Home?

Buying a new home is one of the biggest decisions you’ll make. And if you’re planning to extend in the future, it’s smart to do a bit of research before you commit to a purchase.

At Plan It UK, we’ve helped hundreds of homeowners design and plan their dream extensions. To make sure you’re buying a property with great potential for growth, here are some essential tips to keep in mind when house-hunting.

1. Check for Previous Planning Approvals on the Street

The first thing to do is see what extensions or alterations have been approved nearby. This will give you a good idea of what’s possible on the property you’re considering.

How to do it:

• Search Google for “Planning Search [Insert your council name here]” and head to their Search Planning Applications page (you’ll usually find this under the “Planning” section on your local council’s website).

• Type in the road name and see what planning applications have been granted nearby.

• Look for the “Documents” button on approved planning applications — this will show you the exact plans and layouts that were approved, so you can see what’s worked for other homes on your street.

• Extra Tip: When doing your research, it’s important to remember that there are different rules for flats/maisonettes and houses. For example, external changes to flats/maisonettes will always require planning permission because permitted development rights don’t apply.

2. Understand Local Planning Rules

Before buying a home, it’s important to understand the local planning rules to ensure that an extension is feasible on the property you’re interested in.

How to do it:

• Simply search on Google for “Residential Extension Supporting Planning Document/Guidelines [Insert your council name here].”

• This should lead you to the local planning guidelines for home extensions, outlining what is and isn’t allowed in your area.

• Extra Tip: Ask your solicitors to confirm whether there are any planning constraints to be aware of. For example, if you’re buying a house, does it benefit from permitted development rights? If the solicitors can’t provide this information, get in touch with us and we’ll do our best to find out for you.

Knowing these rules can save you a lot of time and hassle later. For example, in some areas, there are strict rules around Conservation Areas, Greenbelt, National Parks, National Landscapes or Listed Buildings, all of which may limit what you can do.

3. Check for Similar Extensions in the Area on Google Maps

Google Maps is an easy way to spot homes in your desired area that might have already completed extensions. It can give you a quick visual of whether other properties in the street have successfully extended, and give you a feel for what might be possible on your new home.

How to do it:

• On Google Maps, zoom into the street you’re looking at.

• Use Street View and 3D Aerial View to see if any homes have visible extensions, conservatories, or loft conversions.

This can be a good indication that other homeowners have received approval for similar work, which increases your confidence that your future plans might be achievable too.

4. Look at the Layout and Condition of the Property

The type of home you buy can also affect what you’re able to do with it in the future. Some properties might have limited potential for extension due to internal layout, restrictions like shared walls, or even the type of building materials used.

What to consider:

• Space: Does the home have room to expand, either outwards or upwards? If the property has already been extended significantly, this can be a barrier to getting future extensions approved.

• Building structure: Some homes might have structural issues or limitations that could make extensions tricky or costly.

• Orientation: The direction the property faces might impact what type of extension works best in terms of natural light, as well as heating and cooling efficiency.

5. Talk to Plan It UK Before You Buy

Before you sign on the dotted line, it can be incredibly helpful to reach out to a professional like us at Plan It UK. We can give you some pre-purchase advice about your potential home and whether an extension is realistic for the space.

How we can help:

• We can assess the property’s extension potential and provide advice on what’s feasible within the local planning rules.

• We can help you understand the budget and timescales involved in extending the property, so you’re prepared.

• We’ll highlight any design challenges that could come up, allowing you to make a more informed decision.

6. Understand the Local Market

Another thing to consider is the market value of homes in the area. You’ll want to ensure that after extending, your home will still be in line with others in the street, or at least won’t exceed the general property value cap for your area.

How to do it:

• Look at sold prices for similar homes in your area on websites like Rightmove or Zoopla.

• Speak to a local estate agent about what the potential resale value might be once the extension is complete.

Knowing the market cap will help you understand if your extension investment will give you the return you expect — and avoid overcapitalising.

7. Assess Access and Building Logistics

The practicality of constructing your extension is often overlooked when buying a home.

What to consider:

• Access: Do you have good access to the back of the property if you plan to extend outward?

• Neighbours: Are there any shared walls or close neighbours who might make an extension more complicated (or require a Party Wall Agreement)?

• Freehold vs Leasehold: If you’re buying a flat or maisonette, you will usually need to obtain consent from the freeholder (or other freeholders) before making any structural changes. If the freeholder is a housing association or the council, this can make the process longer and more expensive (but not impossible). 

Final Thoughts: Plan Ahead, Build Smart

Buying a home is an exciting journey, and planning for the future by considering the potential for extensions is a smart way to ensure your investment pays off long-term.

At Plan It UK, we can help guide you in your decision-making process and provide expert advice on whether a property is suitable for the kind of extension you have in mind. We’re here to help, every step of the way.

Looking to buy a property and need extension advice?
Reach out to Plan It UK today and let us help you make an informed decision before you make that offer. Click here to book your free consultation.