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Single Storey vs Double Storey Extension — Which Adds More Value?
This is the question we're asked most often at the first site visit. The honest answer depends on your current layout, your budget ceiling, and how long you plan to stay in the house — but the cost-per-square-metre arithmetic genuinely does favour one option in most cases.
Client Reviews
What Our Clients Say
“Pindi is an excellent tradesman. His attention to detail is second to none and he's a really nice guy to work with. Highly recommend.”
James Graham
“Pindi did a fantastic job with my kitchen. He understood my requirements from the start and I was very happy with the finished result. His workmanship was exceptional.”
Lisa Creek
“I used Pindi Sahota for a house conversion, all works were carried out professionally.”
Aniket Patel
The Cost Comparison
| Single Storey | Double Storey | |
|---|---|---|
| Typical cost | £90,000 – £135,000 | £135,000 – £220,000+ |
| Typical duration | 10–14 weeks | 16–22 weeks |
| Added floor area | Ground floor only | Ground + first floor |
| Planning likelihood | Often permitted development | Usually requires full planning |
A double storey extension roughly doubles the usable floor area added for considerably less than double the cost — because you're sharing one set of foundations, one roof structure and one set of groundworks across two floors instead of one. Per square metre, a double storey extension is almost always the more cost-efficient option.
Why Most Homeowners Still Choose Single Storey
Cost-per-square-metre isn't the only variable. A single storey kitchen extension solves a specific, immediate problem — a cramped kitchen, no connection to the garden — without disturbing the bedrooms above or requiring full planning permission in most cases. It's also a smaller, faster, less disruptive project to live through.
When Double Storey Makes Sense
- ✓You need an extra bedroom or bathroom as well as more downstairs space
- ✓Your plot genuinely has room for the larger footprint a double storey extension needs
- ✓You're planning to stay in the house long-term and want to maximise value added in one project rather than two
- ✓You're prepared for the longer planning process and build programme
Our Recommendation Process
We don't default to recommending the bigger, more expensive option. At the free site visit, Pindi assesses your plot, current layout and budget honestly, and will tell you directly if a single storey extension solves your actual problem more efficiently than a double storey one would.
FAQ
Related Questions
Does a double storey extension always need full planning permission?
In most cases, yes — double storey side extensions in particular fall outside permitted development limits far more often than single storey rear extensions do.
Can I build a single storey extension now and add a second storey later?
Yes, this is a common approach — we can design the single storey extension's foundations and structure to support a future second storey, reducing cost if you extend upward later.
Ready to Start Your Project?
Free written quote from your local Berkshire building contractor — usually within 10 working days, depending on the size of your project.