Building Regulations Exemptions: What Doesn't Need Approval — Schedule 2 Guide
Quick Answer: Many small building works are exempt from Building Regulations under Schedule 2 of the Building Regulations 2010. Key exemptions include: small detached outbuildings under 15m² (or 30m² if non-combustible), conservatories under certain conditions, porches, domestic greenhouses, carports, and certain temporary buildings. Most exemptions have specific conditions — check area, proximity to boundary, and use carefully. If in doubt, check with your local Building Control Body (BCB) rather than assuming exemption applies.
Summary
Building Regulations apply to the erection, extension, and material alteration of buildings in England and Wales. However, Schedule 2 of the Building Regulations 2010 lists categories of buildings and works that are exempt — meaning no full plans or building notice application is required and no Building Control approval is needed.
This is different from planning permission. A building can be permitted development (no planning required) but still require Building Regulations approval — for example, a large garage. Conversely, some works require planning but are exempt from Building Regulations. The two systems are independent and must be checked separately.
For tradespeople, knowing the limits of Schedule 2 prevents unnecessary delays (making applications for exempt work) and protects against enforcement action (assuming exemption applies when it does not).
Key Facts
- Schedule 2 categories — Class 1 (buildings not frequented by people, e.g. detached garage), Class 2 (greenhouses, agricultural buildings), Class 3 (temporary buildings), Class 4 (ancillary buildings), Class 5 (small detached buildings), Class 6 (extensions), Class 7 (conservatories, porches, carports)
- Class 5 — small detached buildings — exempt if: floor area ≤30m² AND the building is situated at least 1m from any boundary; OR floor area ≤15m² regardless of boundary distance; in both cases, no sleeping accommodation
- Combustibility condition — Class 5 buildings over 15m² and within 1m of a boundary must be constructed from non-combustible material (the Regulations specify a materially non-combustible structure)
- Conservatories (Class 7) — exempt only if: separated from dwelling by a door or wall; roof is more than 50% translucent; floor area ≤30m²; the conservatory is built at ground level; not used as a bedroom
- Porches (Class 7) — exempt if: floor area ≤30m²; roof and any wall not exceeding 1.5m in height are translucent; at ground level
- Carports (Class 7) — exempt if: open on at least two sides; floor area ≤30m²
- Extensions as Class 6 — certain single-storey extensions are exempt from some but not all regulations — importantly, extensions are generally NOT fully exempt; they are notifiable but may use the approved inspector route
- Material change of use — converting a building to a different use (e.g., garage to habitable room) is almost never exempt; new use triggers full compliance with applicable Parts
- Electrical work — not covered by Schedule 2 structure exemptions; electrical work has its own notifiable/exempt categories under Part P (minor works by householder; major works by registered competent persons)
- Wales — similar framework but some differences in details; the Welsh regulations govern
- Partial exemption — some work may be exempt from specific Parts but not others; e.g., a single-storey extension may not need structural calculations (Part A) assessed if small enough, but Part L energy efficiency still applies
Quick Reference Table
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Try squote free →| Work Type | Exempt from Building Regs? | Key Conditions |
|---|---|---|
| Detached outbuilding ≤15m² | Yes (Class 5) | No sleeping accommodation |
| Detached outbuilding 15–30m² | Yes if ≥1m from boundary (Class 5) | Non-combustible if within 1m |
| Conservatory ≤30m² | Yes (Class 7) | Thermally separated; translucent roof; ground level; no bedroom |
| Porch ≤30m² | Yes (Class 7) | Translucent roof/wall; ground level; existing door retained |
| Carport ≤30m² | Yes (Class 7) | Open at least two sides |
| Greenhouse (domestic use) | Yes (Class 2) | Not for sale or trade growing |
| Fence, gate, garden wall | Generally yes | Max 2m high (1m adj highway) — planning rule; no regs requirement unless structural/retaining |
| Replacement windows (same-for-same) | Notifiable but not full plans | Must use FENSA/Certass registered installer, OR Building Notice |
| Extension (single-storey) | No — notifiable | Submit building notice or full plans; energy/structural standards apply |
| Loft conversion (habitable room) | No — notifiable | Part A structure, Part B fire, Part L energy, Part F ventilation, Part P electrical all apply |
| Garage to habitable room conversion | No — notifiable | Material change of use; Part L, Part B, Part F, Part P all triggered |
Detailed Guidance
Class 5 — Small Detached Buildings in Detail
The most commonly misapplied exemption. The conditions:
Floor area ≤15m² (no boundary restriction): The building can be sited at any distance from the boundary. Size limit only. No sleeping accommodation permitted (bedroom/holiday let removes exemption).
Floor area 15–30m²: The building must be sited at least 1m from any property boundary OR must be constructed from substantially non-combustible materials.
Non-combustible construction means walls and roof of brick, block, concrete, metal, or other non-combustible materials — a standard timber-frame with timber cladding would NOT meet this unless the cladding and structure are non-combustible (e.g., a steel portal frame with concrete board cladding).
What is excluded:
- Any building containing sleeping accommodation — the 1m/30m² exemption does not apply; if anyone sleeps there, it's habitable space and requires full Building Control
- Any building connected to mains drainage — drainage connection triggers Part H (drainage) requirements; this does not remove the structural exemption but drainage work is separate
- Any building with gas or electrical installation — the electrical work has its own competent person route (Part P); the gas work is always Gas Safe-notifiable
Conservatory Exemption Conditions
The Part L exemption for conservatories is discussed in detail in conservatory planning, but the Schedule 2 Building Regulations structural exemption is different. A conservatory is exempt from Building Regulations structure/fabric requirements only if:
- Floor area ≤30m² — if larger, full Building Regulations apply including Part A structure, Part L energy, Part C moisture
- Separated from dwelling — there must be a door or wall between the conservatory and the main house; if the wall is removed to open the conservatory directly into the house, the exemption is lost
- Translucent roof — more than 50% of the roof must be translucent (glass or polycarbonate); an all-tile solid roof makes it an extension, not a conservatory
- Ground level — not an upper-storey conservatory
- Not used as sleeping accommodation
When the exemption applies, no Building Control notification, no full plans, and no inspector visits are required (unless there are associated structural works like removing a wall between house and conservatory — which requires Building Control for the structural alteration).
Permitted Development vs Building Regulations: Getting the Balance Right
These are the most commonly confused concepts:
Example 1: Large garage (60m²)
- Planning: Permitted development if within the limits (up to 50% of garden covered, etc.) — likely yes
- Building Regs: Not exempt (over 30m²) — must submit building notice or full plans Result: Can build without planning but needs Building Regulations
Example 2: Rear extension (30m², single-storey)
- Planning: Permitted development (under 3m for attached; 4m for detached) — yes
- Building Regs: Not exempt — must notify Building Control; Part A (structure), Part L (energy), Part C (damp), Part B (fire) all apply Result: Can build without planning but needs Building Regulations
Example 3: 12m² garden shed
- Planning: Permitted development — yes
- Building Regs: Exempt (Schedule 2, Class 5) — yes Result: Neither planning nor Building Regs required
When Exemption Does Not Apply (Common Mistakes)
Converting a garage to a room — even if the garage was originally exempt, changing its use to habitable accommodation is a material change of use that triggers full Building Regulations compliance for the converted space
Electrical work in an exempt building — the building being Schedule 2 exempt does not exempt the electrical installation from Part P; competent person self-certification or Building Control notification still required for notifiable electrical work
Drainage connection — connecting any building to public sewer or private drainage system is not exempt; Part H drainage regulations apply
Building in flood risk zone — some exemptions are more limited in high-risk flood zones; check Flood Risk Zones 2 and 3
Over-14-day temporary buildings — temporary buildings intended to be in place for more than 28 days (longer in some definitions) lose their temporary exemption; permanent installation of what was described as temporary is also not exempt
Frequently Asked Questions
My customer wants to use their exempt garden building as a home office — does that change anything?
An occasional home office use (a desk in a garden building) typically doesn't change the exemption status, as it is not "sleeping accommodation" and not a material change of use. However, if the customer intends to use it for a business that requires planning consent, or if people other than the household use it as a place of work, different considerations may apply (including the Workplace Regulations). For purely personal use as a home office, the Schedule 2 exemption generally holds.
Can I install a toilet in an exempt building?
Yes, but the drainage connection is a separate matter. The building structure remains exempt, but the installation of a new toilet (notifiable electrical, if applicable) and connection to drainage must comply with Part H (drains). You may need to submit a building notice just for the drainage work, even if the building itself is exempt.
Does an exempt building still need planning permission?
These are separate systems. A building can be exempt from Building Regulations but still require planning permission. Garden buildings are typically permitted development for planning (subject to conditions), but always check the specific planning rules for the location — especially in Conservation Areas or where Article 4 Directions remove permitted development rights.
Regulations & Standards
Building Regulations 2010, Schedule 2 — Complete list of exempt buildings and works
Building Act 1984 — Parent legislation for Building Regulations
The Building Regulations 2010 (as amended) — All current applicable versions
Planning Practice Guidance (England) — Permitted development vs planning permission distinction
MHCLG: Building Regulations 2010 Schedule 2 — Legislation.gov.uk — full text of exemptions
Planning Portal: When Do You Need Building Regulations — Worked examples
LABC: Exempt Work — Local Authority Building Control guidance
building regs overview — Full introduction to Building Regulations and Part structure
conservatory planning — Conservatory rules in detail
retrospective approval — What to do when exempt status was assumed incorrectly
planning permission — Permitted development rules