Rear extension layout
Rear extension layout ideas before planning or builder prices
A rear extension can be a brilliant answer, but only if it changes the way the whole ground floor works. The footprint alone does not tell you where the kitchen, dining table, doors, storage or daylight should go.
We help you explore the rear-extension idea alongside the existing house, so you can decide whether to extend, open up, reconfigure or combine those moves before committing to the next stage.
Short answer
What this means
A rear extension layout shows how a proposed extension connects to the existing rooms and garden, rather than treating the new square metres as a separate box.
For your home
Why it matters
It is much cheaper to test the flow on paper than to discover after planning or on site that the new space creates an awkward kitchen, dark middle room or poor route to the garden.
Next step
What to do now
Send the rear of the house, any estate-agent plan or a sketch of what you had in mind. We will take a first look and help identify a sensible route forward.
Who is behind the advice
Local project advice from Josh and PlanBuild.
The page exists to help homeowners work out the practical route before drawings, structure, permissions and builder pricing become separate conversations.
Who
PlanBuild gives local project advice for homeowners around Poole, Bournemouth and Dorset.
How
We start from photos, address, existing plans, site constraints and the likely approval or build route.
Why
The aim is to point you at the right next step before you waste money on the wrong drawing, quote or contractor conversation.
Good fit
- You want to improve a kitchen, dining or family room at the back of the house.
- You are choosing between a shallow/wide or deeper/narrower extension.
- You want to understand the layout before planning and technical drawings.
Not the right route if
- A confirmed construction package with no need to revisit the plan.
- A guarantee of permitted development or planning approval without assessment.
What to send first
- photos of the rear and inside rooms
- garden/side-access details
- any existing plan
- your priorities for the new space
Related routes
Keep the route connected
House extension plans
House extension plans can mean anything from an early layout idea to a planning or technical drawing set. The right version depends on what stage you are at and what the project needs next.
Open route →Single-storey extension layout
A single-storey extension layout explores the relationship between the new space and the existing home before a preferred design moves into planning or Building Control drawings.
Open route →Kitchen extension layout
A kitchen extension layout tests how the new space connects to the existing house, where the kitchen and table sit, how people move through the room and which structural changes may be needed.
Open route →Planning drawings
Planning drawings explain the existing home, the proposed change and how the project sits on the site so the council can assess it.
Open route →Questions homeowners ask
Before you choose the route
How far should a rear extension extend?
The right depth depends on the existing rooms, daylight, garden, planning route and what the extra space needs to do. It is a layout decision as much as a size decision.
Can I get a first opinion from a rough sketch?
Yes. A rough sketch is enough to start the conversation. It can then be developed into a proper option pack if needed.
Free first response
Tell us what you’re planning.
Whether it’s a bigger kitchen, an open-plan downstairs or a wall you’ve pictured coming down for years, send the details here first. We’ll point you at the cleanest next step:
- “Who do I speak to first?”
- “What’s the actual first step?”
- “Does my project need planning permission?”
- “Do I need Building Control?”
- “Which certificates do I end up with at the end?”
- “Who keeps the whole thing compliant?”
Drop a few details below and we'll tell you who should be involved first: designer, engineer, Building Control or builder.
Start here hub page
Not sure which drawings, approvals or builder route you need?
Use the floor plans hub first. It explains whether your home improvement starts with existing/proposed plans, planning drawings, Building Control, structural calculations or a builder quote pack.
See the floor plans and drawing route →Quickest route: send the project details, or call if it is urgent.