2022 changes to the building regulations for extensions (Part L)
changes to the building regulations
Building Regulations Part L sets the standards for thermal performance and energy efficiency in buildings across the UK. In July 2022, new changes were introduced, significantly impacting home extensions and renovations. If you’re planning an extension or home improvement project, understanding these Building Regulations updates is crucial.
In this guide, we’ll cover:
What Building Regulations Part L means for extensions and existing dwellings Key U-value changes affecting insulation requirements The impact on homeowners, builders, and designers How Melrose Designs can help ensure compliance.
What Are Building Regulations Part L?
Part L of the Building Regulations focuses on reducing heat loss in buildings, improving energy efficiency, and lowering carbon emissions. The new 2022 updates aim to improve insulation standards in both new builds and home extensions.
Why the changes?
The government is pushing for low-energy homes to meet net-zero carbon targets. Existing homes and extensions must now adhere to higher energy efficiency standards. New rules ensure better insulation, reduced heat loss, and improved airtightness.
Key 2022 Updates to Building Regulations Part L
The U-values (which measure heat loss) have been significantly reduced. A lower U-value means better insulation and reduced energy loss.
New U-Value Requirements for Extensions & Existing Buildings
| Building Element | Old U-Value (W/m²K) | New U-Value (W/m²K) (July 2022 Update) |
|---|---|---|
| Roofs | 0.18 / 0.16 (depending on type) | 0.15 |
| Walls | 0.28 | 0.18 |
| Floors | 0.22 | 0.18 |
| Windows | 1.6 | 1.4 |
| Glazed Doors | 1.8 | 1.4 |
| Rooflights | 2.20 | 2.20 |
What This Means for Home Extensions
Thicker insulation is now required for walls, floors, and roofs. Larger glazed areas (windows & doors) must be balanced with higher insulation elsewhere. New heating systems must be compatible with low-carbon solutions. Air-tightness testing is now mandatory for all extensions.
Example: How These Changes Affect a Standard Extension
Before July 2022, a simple brick-built extension with a 100mm cavity wall and 50mm insulation met regulations. Under the new rules, the same extension now requires:
A wider 140mm cavity to accommodate 90mm insulation Thicker roof insulation (50mm extra beneath rafters) Longer wall ties, deeper windowsills, and additional structural adjustments
How the Changes Affect Homeowners and Builders
Higher costs: Increased insulation requirements may slightly raise construction costs. Longer approval times: More detailed Building Regulations drawings are required. More sustainable homes: Improved insulation means lower energy bills and better living conditions.
At Melrose Designs, we help homeowners and builders navigate these changes, ensuring Building Regulations compliance with expert construction drawings.
Other Building Regulations Updates You Should Know
Part F: Ventilation Standards
- Homes must include ventilation systems to improve air quality.
- Extractor fans must be upgraded in kitchens and bathrooms.
Part O: Overheating Prevention
- New builds must follow overheating guidelines using thermal modeling.
- Large south-facing windows may require shading solutions.
Part S: EV Charging Requirements
- All new homes and extensions must provide infrastructure for electric vehicle charging.
- 7kW untethered EV chargers must be installed in new builds.
How to Ensure Compliance with the New Building Regulations
If you’re planning an extension, loft conversion, or renovation, you must submit Building Regulations drawings to your local council or private building control inspector.
Step-by-Step Process for Approval
Consultation: Meet with a Building Regulations expert like Melrose Designs. Site Survey: Accurate measurements and assessments of existing structures. Detailed Drawings: Plans showing how your extension meets Part L requirements. Submission & Approval: Drawings are sent to St Helens Council or an approved inspector. Construction & Inspections: The build is checked for compliance at key stages.
Why Choose Melrose Designs for Building Regulations Compliance?
At Melrose Designs, we specialize in Building Regulations-compliant construction drawings for extensions, new builds, and home renovations.
Why work with us?
Expert knowledge of Part L compliance Fast and accurate Building Regs drawings Advice on insulation, heating, and ventilation Support from initial consultation to final approval
Don’t risk non-compliance—work with experts who understand the latest Building Regulations!
Get Your Building Regulations Drawings Approved Today!
Planning an extension or renovation? Need Building Regs drawings in St Helens? Our team at Melrose Designs ensures your project meets all new 2022 Building Regulations standards.
Contact us today for expert guidance and a free consultation!
