Kitchen rear extensions in Nottingham
A kitchen rear extension pushes the back of your kitchen out into the garden, usually across the width of the house, and replaces the old back wall with a steel beam and wide glazed doors. This page covers what’s specific to that job: the structure over the old wall, the doors and glazing, the step down to the patio and how much garden you give up.
For kitchen layout, moving plumbing and gas, and the fit-out itself, see our guide to kitchen extensions.
What changes when the kitchen moves outward
Most kitchen rear extensions add somewhere between 3m and 6m to the back of the house. The new walls and roof are the simple part. The work that needs most thought is where the old kitchen meets the new one.
Opening up the old rear wall
The back wall of the house carries the floor, and usually the wall, above it. Taking it out means a steel beam designed by a structural engineer, with each end bearing on padstones, piers or posts that carry the load down to suitable foundations. Temporary props hold the house up while the wall comes out.
- The engineer’s calculations go to building control with the application.
- Existing foundations under new posts may need checking or new pads.
- Where the beam bears on a shared wall, a party wall notice is usually needed.
- The steel usually needs fire protection once it’s in, as specified.
What happens to the old kitchen
The old back wall is often where the sink, the window and the soil stack are. Once it goes, the old kitchen becomes the middle of a deeper room and usually its darkest part.
- Tall units, the fridge and storage often move to the old part of the room.
- Dining and seating move towards the light and the garden doors.
- The soil stack and drains may need rerouting before the wall comes out.
Opening the kitchen onto the garden
The garden wall of a kitchen rear extension is usually mostly glass. The choice of doors affects the view, how much of the opening clears and how the room feels in winter.
Bi-fold doors
Fold back to open almost the full width in summer. When closed there are more frames in the view, and the folded panels take up space inside or out.
Sliding doors
Larger glass panels and slimmer frames give a clearer view when closed. Only part of the opening clears, because the panels slide behind each other.
French doors and fixed glazing
A pair of doors with fixed panels either side opens less, but leaves wall space for units where the kitchen runs along the garden side.
Rooflights and lanterns
A deep kitchen needs daylight in the middle as well as at the doors. Rooflights or a lantern over the island or table bring light to the part of the room furthest from the garden.
How much glass is allowed
Building regulations set a guide limit for glazing in an extension: windows, doors and rooflights of about 25% of the new floor area, plus the area of any windows and doors lost from the old wall. More is possible if the design makes up for the extra heat loss elsewhere, shown by calculation.
Sun and shading
A large glazed wall facing south or west can make the kitchen hot in summer. A roof overhang, solar control glass or blinds help, and are easier to plan in than to add later.
Levels, the patio and how much garden you keep
Extending the kitchen into the garden changes the garden too. It’s worth designing the outside space as part of the project rather than after it.
Level or stepped threshold
A flush floor from kitchen to patio looks neat, but the new floor has to stay above outside ground and the damp-proof course. A level threshold usually means setting the patio lower at the doors, adding a drainage channel in front of them and choosing doors with a low threshold made for it. A single step down to the patio is simpler.
- On a sloping garden the kitchen may sit a step or more above the lawn.
- Where the garden rises, the extension may need to be cut into the slope with a retaining wall.
Losing part of the garden
A 3m to 4m extension takes that depth off the lawn or patio across its width. Under permitted development, extensions and outbuildings together can’t cover more than half the land around the original house, but the practical question is usually whether what’s left still works.
- Room for a table and chairs outside the new doors.
- Space for bins, bikes and a washing line.
- On a terrace, a clear route to the back gate.
What drives the cost of a kitchen rear extension
Kitchen extensions usually cost more than a plain rear extension of the same size because of the kitchen and the services. Indicative price ranges are on our kitchen extensions page. After a free site survey you’ll receive a written, itemised quotation.
The structure
The width of the opening, the size of the steel and whether new posts need their own foundations.
The glazing
Door type, size and frame material, and whether you choose a lantern or flat rooflights.
The kitchen
Units, worktops and appliances. Check whether each quote includes the kitchen or only the building work, so you compare like with like.
Planning rules for kitchen rear extensions
A kitchen rear extension follows the same rules as any other rear extension. Whether it needs a planning application depends on its depth and height, the type of house and any local restrictions. Building regulations approval is needed either way.
Permitted development
Many single-storey kitchen rear extensions may fall under permitted development, depending on the property and any restrictions. In outline:
- Depth up to 3m for an attached house or 4m for a detached house, from the original rear wall.
- No more than 4m high, with eaves no higher than 3m within 2m of a boundary.
- Extensions and outbuildings covering no more than half the land around the original house.
- A layout that wraps into the side return is also assessed under the side extension rules.
Prior approval and planning applications
Deeper schemes and properties without full permitted development rights take a different route. Your property needs to be checked before you rely on any of these.
- Prior approval for single-storey rear extensions up to 6m (attached) or 8m (detached), not available in conservation areas.
- A householder planning application where limits are exceeded, rights have been removed by an Article 4 direction or earlier condition, or the house is listed.
- A Lawful Development Certificate to confirm permitted development status in writing.
- Party wall notices where you build on or near the boundary.
Kitchen rear extension FAQs
What’s the difference between a kitchen rear extension and a kitchen extension?
A kitchen extension is any extension built to enlarge a kitchen, including side-return and wrap-around designs. A kitchen rear extension is specifically the kitchen pushed straight out into the back garden, so the main questions are the steel over the old rear wall, the garden doors and the levels outside.
Do I need a steel beam to extend my kitchen at the back?
Usually, yes. The old rear wall carries the structure above, so opening it up needs a beam designed by a structural engineer, with suitable supports at each end. Building control checks the calculations and inspects the steel before it’s covered.
Bi-fold or sliding doors for a kitchen extension?
Bi-fold doors open almost the full width but show more frame when closed. Sliding doors give a clearer view with bigger panels but only open part of the width. The choice depends on how often you’ll have the doors fully open and how much of the view you want in winter.
Can I have a level floor from the kitchen to the patio?
Often, yes, but it needs designing in. The patio usually has to be set lower at the doors, with a drainage channel in front and doors made for a low threshold, so that rain can’t reach the floor or the damp-proof course. A single step down is the simpler option.
Do I need planning permission for a kitchen rear extension?
Not always. Many single-storey kitchen rear extensions may fall under permitted development, usually up to 3m deep for an attached house or 4m for a detached house, if the property qualifies. Deeper schemes may need prior approval or a planning application. Building regulations approval is needed either way.
How long does a kitchen rear extension take?
The extension itself often takes around 8 to 12 weeks on site once approvals are in place. With the new kitchen fitted as part of the same job, around 10 to 14 weeks on site is more typical, plus time beforehand for design, approvals and kitchen lead times. It’s an estimate rather than a guarantee.
Is the kitchen itself included in the extension quote?
Not always. Some quotes cover only the building work and treat the kitchen as a separate item. Ask for the units, worktops, appliances and fitting to be itemised so you can compare quotes like for like.
Plan your kitchen rear extension
Book a free site survey. We’ll look at the back wall, the drains and the garden levels, then follow up with a written, itemised quotation. You can also browse our project gallery and customer reviews, and ask at the survey for a past customer you can speak to.