Transform Your Home with a Rear Extension
A single storey rear extension is the most popular way to add space to your home — and for good reason. By extending into your garden, you can transform a cramped kitchen into a bright, open-plan living space that brings the outdoors in.
At Spectra Extensions, we specialise in single storey rear extensions across Milton Keynes and the surrounding areas. Using RADIX screw pile foundations, bespoke structural engineering, and premium brick slip finishes, we deliver extensions that look exactly like traditional builds — but completed in 4-5 weeks, not months.
What a Rear Extension Can Do for Your Home
A rear extension opens up possibilities that simply aren't available with your existing layout. Whether your kitchen feels too small for family meals, your living room needs more natural light, or you want a proper connection between indoor and outdoor space, extending to the rear is the answer.
Open-Plan Kitchen-Diners
Knock through your existing rear wall and extend to create the open-plan kitchen-diner you've always wanted. Room for a proper island, dining table, and still have space to move.
Bi-Fold Doors to the Garden
Floor-to-ceiling bi-fold or sliding doors flood your new space with natural light and create a seamless connection between your kitchen, living area, and garden.
Light-Filled Family Space
A south or west-facing rear extension can be designed with skylights and glazed doors to maximise natural light throughout the day, creating a warm and inviting family room.
Room for the Whole Family
Rear extensions are ideal for growing families. Create a space where everyone can cook, eat, play, and spend time together without feeling on top of each other.
Sizes and Permitted Development
The good news is that most single storey rear extensions fall within permitted development rights, meaning you don't need to apply for planning permission. This saves time, money, and the uncertainty of waiting for council approval.
How Far Can You Extend?
Under current permitted development rules for single storey rear extensions:
- Detached houses — extend up to 4 metres from the rear wall (or up to 8 metres under the larger home extension scheme with prior approval)
- Semi-detached and terraced houses — extend up to 3 metres from the rear wall (or up to 6 metres under the larger home extension scheme with prior approval)
- Maximum height — 4 metres at the eaves
Not sure about your property? Permitted development rights can vary for listed buildings, conservation areas, and properties that have already used some of their PD allowance. We check everything during your free site visit and advise you on exactly what's possible.
A typical rear extension adds between 15 and 30 square metres of usable floor space. Even a modest 3-metre projection across the full width of your house can completely transform how you use your ground floor.
How Spectra Builds Your Rear Extension
Our approach combines advanced construction technology with traditional craftsmanship. The result is a rear extension that's indistinguishable from a conventional build — but delivered faster, with less disruption, and at a competitive price.
RADIX Screw Pile Foundations
Instead of weeks of excavation and concrete, we install RADIX screw piles in 1-2 days. No diggers tearing up your garden. No concrete trucks blocking your drive. No waiting for foundations to cure. Your build starts immediately.
Bespoke Structural Engineering
Every Spectra rear extension is individually engineered by our structural engineers. The design accounts for your existing rear wall, drainage, services, and any structural openings needed to connect old and new.
Premium Brick Slip Finishes
Your new rear extension is finished with premium brick slips that match your existing brickwork. The join between old and new is seamless — your extension will look like it has always been part of the house.
Complete in 5-6 Weeks
From foundations to handover, a typical Spectra rear extension takes just 4-5 weeks. Traditional builds of the same size can take 3-6 months. Less time on site means less disruption to your daily life.
Rear Extension Costs
Every rear extension is bespoke, so costs depend on the size, specification, and complexity of your project. As a planning guide, we recommend budgeting from £2,200 + VAT per square metre. We provide a fixed price guarantee — the price we quote is the price you pay, with no hidden extras.
We provide a free initial estimate after our site visit, followed by detailed drawings and a fixed, confirmed price before any work begins. No hidden costs, no surprises. Visit our prices page for more detail on how our pricing works.