Professional, builder-ready drawing packages for extensions, lofts, porches, garages, garden rooms and more — designed to Permitted Development parameters and supplied as sold.
PERMITTED HOMEOWNER GUIDES
Our illustrated, practical guides help you understand the rules, explore design options and budget with confidence — before you commit to building work.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
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Rules, design options, costs and next steps.
View guideSemi-detached houses have more PD flexibility than terraced houses — including the right to build a single-storey side extension — but the rules are strict to protect neighbours and the street scene.
Semi-detached houses have the full range of permitted development rights, including the right to add a single-storey side extension under Part 1 Class A. The key restrictions are: single-storey side extensions cannot exceed half the width of the original house; two-storey side extensions always require planning permission; rear single-storey extensions up to 3m (or 6m under Prior Approval); and loft conversions up to 50m³. The shared party wall with the neighbouring semi means any extension involving the party wall will need to comply with the Party Wall etc. Act 1996.
Unlike terraced houses, semi-detached houses have a PD right to build a single-storey side extension. The key conditions:
| Extension type | Semi-detached limit |
|---|---|
| Single-storey rear | 3m from original rear wall (6m under Prior Approval scheme) |
| Two-storey rear | 3m from original rear wall, 7m minimum from rear boundary |
| Wraparound | Not permitted development — requires planning permission |
Loft conversions in semi-detached houses are permitted development under Part 1 Class B:
Rear dormers are the standard approach for semi-detached loft conversions — adding a large rear dormer to maximise headroom while keeping the front roof slope intact.
Any extension or loft conversion that involves work to the shared party wall with your neighbour will be subject to the Party Wall etc. Act 1996. This requires you to serve a Party Wall Notice on your neighbour before starting work. If your neighbour consents, work can proceed after 14 days. If they dissent or don’t respond, a Party Wall Agreement (an award made by party wall surveyors) is required before work can start. Party wall issues are separate from planning — you can have PD rights and still need to comply with the Act.
Outbuildings for semi-detached houses follow the same Part 1 Class E rules as other houses. The 50% curtilage coverage limit and height limits apply. A detached garage in the side of the plot is very common for semi-detached houses — check that the garage won’t project in front of the principal elevation, which would remove the PD right and require planning permission.
Ask PERMITTED — quick answers on extensions, lofts, garages and garden rooms. If your project fits the rules, choose a fixed-price drawing package. If it doesn’t, YPDS Architectural Services, our parent practice in Leeds, can advise on planning.
Planning a project? Browse our permitted development drawing sets — fixed price, supplied exactly as sold and emailed to you as a PDF.
Each one is already drawn. You choose the material, roof and options we actually draw, and that is the package you receive.
A practical entrance area that adds space and improves the look of your home.
£350
A popular way to create a larger kitchen, dining or family area.
£900
Adds valuable space to the side of your home for a kitchen or utility.
£900
Turns unused loft space into a bedroom, office or additional living area.
£1,500
A flexible, detached space for work, leisure or extra living space.
£350
Secure parking or useful storage, single or double.
£350
Significantly more living space across both floors.
£1,400
A bright, glazed room connecting your home to the garden.
£900PERMITTED HOMEOWNER GUIDES
Our illustrated, practical guides help you understand the rules, explore design options and budget with confidence — before you commit to building work.
Explore all guidesRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
View guideRules, design options, costs and next steps.
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Maximize your property’s footprint with precision and ease. Permitted provides complete design for Permitted Development Rights. Our packages are designed around the Permitted Development limits, so many projects can proceed without a full planning application.
PERMITTED is operated by Yorkshire Property Design Services Limited, registered in England and Wales under company number 12698267.
Registered office: Ground Floor, Techno Centre, Station Road, Horsforth, Leeds, LS18 5BJ
Business contact address: Wira House, Ground Floor, Suite 5, Ring Road, West Park, Leeds, LS16 6EB
