Energy-Efficient House Extensions in Dorset

HUP house extensions typically cost £2,300–£3,000 per m², depending on layout and specification. A standard 3m × 3m extension sits around £20,700–£27,000, with larger builds scaling proportionally.

More details are available on our house extension pricing page.

It depends on the type of build, but most traditional extensions take 10 to 24 weeks once construction begins. That doesn’t include time for planning or approvals, which can add a few extra weeks. Build time can vary depending on:

• The complexity of the design
• Weather delays and ground conditions
• Access to the site

With modular systems like hup!, things move faster because panels are pre-manufactured off-site, the on-site build will be weather-tight within a week, meaning less disruption and a quicker finish.

In many cases, yes, most people do stay in their homes while the extension is being built. That said, it depends on the scope of the work and the level of disruption you’re comfortable with. Things to consider include:

• Which part of the house is being extended
• Whether utilities like water or electricity need to be shut off
• Access routes for builders and materials
• Noise, dust, and general disruption
• If you’ve got young kids, pets, or work from home

Some people choose to stay with family or book short-term accommodation during the noisiest stages. But with good planning, it’s often possible to remain at home throughout.

There are a few common ways to finance a house extension, depending on your situation and the size of the project:

• Savings: Ideal if you’ve been planning, or the extension is small enough to cover without borrowing.
• Remortgaging or a home improvement loan: Many homeowners release equity from their property or take out a specific loan for renovations.
• Personal loans or finance plans: These can work well for more minor upgrades, such as garden offices or conservatory roof replacements.

It’s worth speaking to a financial adviser before committing, especially if you’re planning a larger extension or want to explore how it may affect your mortgage options.

In most cases, yes. A well-planned extension can boost both your home’s value and its appeal to future buyers. The actual increase depends on what you build, how well it’s done, and where you live. Extensions often add the most value when they:

• Create a larger, open-plan kitchen or living space
• Add an extra bedroom or bathroom
• Improve the overall layout and flow of the home
• Include energy-efficient features and modern materials
• Blend seamlessly with the existing architecture
• Are fully signed off with building regulations and planning approval

While not every extension guarantees a profit, it can often increase your home’s resale value and make it more attractive to buyers.

Not always. Many extensions fall under Permitted Development Rights, which means you can go ahead without applying for full planning permission, as long as the design stays within certain limits.

You’ll usually need permission if the extension is too large, changes the front of your property, affects a public road, or you’re in a conservation area or a listed building.

For full details on what’s allowed and how to apply, visit our planning permission guide.

Yes, we regularly complete house extensions Bournemouth homeowners can rely on, delivering extra space with minimal disruption across Poole, Christchurch, and the wider Dorset area.