Planning Rules
Terraced House Permitted Development: What Can You Build? (2025)
Terraced houses have more restricted permitted development rights than detached or semi-detached houses — particularly for rear extensions and loft conversions. Here’s what you can build without planning permission.
⏱ 6 min read📅 Updated June 2025🏠 England only
Quick Answer
PD rights apply — but terraced houses have smaller size limits than detached houses
Terraced houses have the same categories of permitted development rights as other houses — extensions, loft conversions, outbuildings — but the permitted sizes are smaller. For single-storey rear extensions, the PD limit for a terraced house is 3 metres from the rear wall (6 metres under the Prior Approval neighbour consultation scheme). Loft conversions can add up to 40m³ of roof space. Side extensions require planning permission. Importantly, terraced houses have no permitted development right for side extensions — any side extension needs full planning permission.
Extensions
| Extension type |
Terraced house rule |
| Single-storey rear extension |
Up to 3m from the original rear wall (or 6m under the Prior Approval neighbour consultation scheme). Maximum 4m height. Cannot exceed half the original garden width |
| Two-storey rear extension |
Up to 3m from the rear wall. Must be at least 7m from the rear boundary. Eaves and ridge no higher than the original house |
| Side extension |
Not permitted development — planning permission always required for terraced houses |
| Wraparound extension |
Not permitted development — extends to the side so planning permission needed |
⚠️ Why can’t terraced houses build to the side? Permitted development for side extensions is only available to detached and semi-detached houses (and only on one side for semi-detached). For terraced houses, any side extension — even a small one — requires planning permission. This is to prevent the cumulative impact of side extensions on terrace rooflines and the spaces between houses.
Loft Conversions
Loft conversions in terraced houses are permitted development under Part 1 Class B, subject to:
- Maximum addition of 40m³ of roof space (compared to 50m³ for detached and semi-detached houses)
- No extension beyond the plane of the existing roof slope that fronts a highway
- No addition to the roof that exceeds the highest part of the original roof
- Any roof extension must be set back 20cm from the eaves
- Side-facing windows must be obscure-glazed and non-opening below 1.7m
In practice, the 40m³ limit means most terraced house loft conversions can be done under permitted development — the typical terraced house loft conversion (a rear dormer) adds around 20–30m³.
Outbuildings
Outbuildings (sheds, garden offices, garages) are permitted development for terraced houses under Part 1 Class E, subject to the same rules as other houses:
- Must be in the curtilage and not in front of the principal elevation
- Maximum 50% of the total curtilage can be covered by outbuildings (not counting the original house)
- Single-storey only, up to 2.5m height for flat roofs or up to 4m for dual-pitched roofs
- Must be at least 2m from the boundary if over 2.5m in height
Conservation Areas and Article 4 Directions
Many Victorian and Edwardian terraced streets are in conservation areas, where Article 4 Directions typically remove PD rights for external alterations. In these areas, extensions that would normally be PD require planning permission. Common conservation area restrictions for terraced houses include windows (no uPVC), roofing materials (no plain concrete tiles), and external painting. Check whether your street is in a conservation area before assuming PD applies.
Frequently Asked Questions
Can I extend a terraced house under permitted development?
Yes — rear extensions up to 3m deep (or 6m under the Prior Approval neighbour consultation scheme) are permitted development for terraced houses. Two-storey rear extensions up to 3m deep are also PD. Side extensions, however, are not permitted development for terraced houses and always require planning permission. Loft conversions adding up to 40m³ are also PD.
Can I add a side return extension to a terraced house without planning permission?
No — any side extension (including a side return infill) to a terraced house requires planning permission. Permitted development rights for side extensions only apply to detached and semi-detached houses. A side return is by definition on the side of the house, so planning permission is needed.
How big can a terraced house extension be under permitted development?
A single-storey rear extension on a terraced house can be up to 3m deep from the original rear wall under automatic PD, or up to 6m under the Prior Approval neighbour consultation scheme. For a two-storey rear extension, the PD limit is 3m deep. The extension must be single-storey at the sides, no more than half the width of the original house at the rear, and no higher than 4m (single-storey) or the eaves of the original house (two-storey).
Do terraced houses in conservation areas have permitted development rights?
Terraced houses in conservation areas may have reduced PD rights due to Article 4 Directions. Many councils have made Article 4 Directions in Victorian and Edwardian terraced areas that remove PD rights for external alterations — requiring planning permission for extensions, window changes, and other works. Check with your council whether an Article 4 Direction applies to your address before relying on PD rights.
More on Permitted Development Rights
Extensions, loft conversions, outbuildings, solar panels — our complete guide covers everything you can build without planning permission.
Read the Complete PD Guide →
