Thinking about extending your home? Whether your family is growing, your layout no longer works, or you’re looking to add value before selling — a well-designed extension is one of the smartest investments a homeowner can make.
At Austen Dawson, we’ve helped countless homeowners across the Cotswolds and beyond transform their properties with thoughtful, high-quality extensions. In this post, we’ll share 7 of the most popular and effective house extension ideas — all designed to increase usable space and long-term property value.
1. Rear Kitchen & Family Room Extension
One of the most sought-after upgrades in UK homes, a rear extension creates a spacious, open-plan kitchen-diner and living area — often with bifold doors opening onto the garden. It’s perfect for modern family life and entertaining.
Why it works:
Connects kitchen, dining, and living into one open, sociable space
Brings in natural light with rooflights or full-width glazing
Creates a stunning focal point and improves indoor-outdoor flow
Planning tip: Many rear extensions fall under permitted development, meaning planning permission may not be required — as long as you meet certain size and height limits.
2. Wraparound Extension
A wraparound extension combines a rear and side return extension, usually seen on Victorian and Edwardian homes. It turns underused side alley space into valuable square footage.
Benefits:
Adds width and depth to your ground floor
Ideal for relocating the kitchen and adding utility rooms or larders
Can radically improve layout flow in older homes
Design idea: Consider using Crittall-style glazing, internal crittall partitions, or exposed steelwork to add architectural flair.
3. Two-Storey Rear Extension
Want more space upstairs as well as downstairs? A double-storey extension might be the answer. While it does cost more, the additional square footage can dramatically increase your home’s value.
Typical additions:
A larger kitchen/family space downstairs
An extra bedroom and en-suite or bathroom upstairs
Walk-in wardrobes or a home office
Things to consider:
You’ll need full planning permission, and designs must consider privacy (overlooking neighbours), matching materials, and structural impact.
4. Side Return Extension
If your home has a narrow, underused side alley (common in older terraces and semis), a side return extension can widen your kitchen or living space without sacrificing garden depth.
Advantages:
Makes the most of wasted side space
Ideal for galley kitchens and narrow plots
Great light potential with roof glazing and open-plan design
Planning insight: Side returns often fall under permitted development, but always check if you’re in a conservation area or listed building.
5. Loft Conversion with Dormer
While not a ground-floor extension, a loft conversion is one of the most cost-effective ways to add space — especially for growing families or home workers.
What you can create:
A generous master suite with en-suite
A light-filled home office or creative studio
A guest room or teenage retreat
Dormer conversions offer the most usable space and can often be done under permitted development rules.
6. Garden Room or Home Office Pod
Since 2020, remote work has become the norm for many, and demand for detached garden buildings has surged. A fully insulated garden room or office pod can give you space away from the main house.
Use cases:
Home office
Gym or yoga studio
Guest accommodation (with en-suite/shower)
Key points:
Garden buildings under 2.5m high and under 30m² typically don’t need planning permission — but still require careful construction and insulation to meet Building Regs if used year-round.
7. Garage Conversion
If your garage is currently unused or acting as a glorified storage unit, converting it into a habitable room is a low-cost way to gain usable space.
Popular uses:
Utility or boot room
Ground floor WC or shower room
Home office or studio
Playroom or snug
Bonus: You retain your garden and external footprint while unlocking internal space.
How Much Value Can an Extension Add?
The right extension, designed well and built to a high standard, can add 10%–25%+ to your property’s market value — especially if it improves layout, bedroom count, or kitchen space.
For example:
A rear kitchen extension in a 3-bed semi could push the value up by £40,000–£70,000+
A two-storey extension could move a house into a completely new price bracket
A loft conversion can often add 1.5x–2x the build cost in value
Of course, this depends on local demand, build quality, and overall finish — but the returns can be substantial.
Need Help Planning Your Extension?
At Austen Dawson (Construction & Mechanical) Ltd, we offer full design and build services, including:
Advice on permitted development and planning
Accurate cost estimates and budgeting
Structural calculations and building control
High-quality construction with a focus on detail and finish
Whether you’re planning a kitchen extension, loft conversion, or full house remodel — our experienced team is here to guide you from concept to completion.
Let’s talk about your project – Contact us today or call 01367 248417 or fill out the form below and we’ll get back to you.
