If you’re planning a house extension in Hampshire — whether you’re in Swanmore, Hook, or Waterlooville — one of the biggest decisions you’ll face is:

👉 Should I build a single-storey or double-storey extension?

Here’s how to decide which option is right for your home, budget, and long-term goals.

🧱 Single-Storey Extensions: Pros, Cons & Ideal Scenarios

Best for:

• Ground floor kitchen/diner expansions
• Garden-facing living spaces
• Homes with large outdoor plots (e.g. Emsworth, Ashurst)

✅ Pros:

• Lower cost (£1,800–£2,500/m² on average in Hampshire)
• Faster to build and easier to get planning permission
• Minimal disruption to upstairs rooms

🚫 Cons:

• Uses up garden or side access
• No additional bedroom or bathroom upstairs
• May not significantly increase property value in high-demand areas like Winchester or Lymington

🏠 Double-Storey Extensions: Pros, Cons & Ideal Scenarios

Best for:

• Growing families needing more bedrooms
• Creating an en-suite or home office upstairs
• Maximising value in premium locations (e.g. Alton, Romsey)

✅ Pros:

• Much greater space-to-cost ratio
• Adds upstairs AND downstairs square footage
• Better ROI long-term

🚫 Cons:

• Higher cost (£2,200–£3,200/m²)
• May need full planning permission
• Slightly more structural work and disruption

🔍 Planning Tip for Hampshire Homes

In conservation areas like Bishop’s Waltham or Meon Valley, even small extensions may require planning permission. A local architect will assess your site and recommend the best route — especially for double-storey projects.

✅ Final Verdict: Which Should You Choose?

Still unsure? Speak to a local Hampshire architect for a tailored recommendation based on your home, layout, and goals.