Limiting fabric standards
Contents |
[edit] Introduction
The building regulations require that reasonable provision be made to limit heat gains and losses through the fabric of new buildings and works to existing buildings. The approved documents to the buildings regulations set out the limiting standards for the properties of the fabric elements of the building.
[edit] L1A, new dwellings, 2013 edition
Roof | 0.2 W/(m^2K) |
Wall | 0.3 W/(m^2K) |
Floor | 0.25 W/(m^2K) |
Party wall | 0.2 W/(m^2K) |
Swimming pool basin | 0.25 W/(m^2K) |
Windows, roof windows, glazed roof-lights, curtain walling and pedestrian doors | 2.0 W/(m^2K) |
Air permeability | 10.0 m^3/(h.m^2) at 50 Pa |
[edit] L2A, new buildings other than dwellings, 2013 edition
Roof | 0.25 W/(m^2K) |
Wall | 0.35 W/(m^2K) |
Floor | 0.25 W/(m^2K) |
Swimming pool basin | 0.25 W/(m^2K) |
Windows, roof windows, roof-lights, curtain walling and pedestrian doors | 2.2 W/(m^2K) |
Vehicle access and similar large doors | 1.5 W/(m^2K) |
High-usage entrance doors | 3.5 W/(m^2K) |
Roof ventilators (inc. smoke vents) | 3.5 W/(m^2K) |
Air permeability | 10.0 m^3/(h.m^2) at 50 Pa |
[edit] L1B and L2B, existing dwellings and existing buildings other than dwellings, 2010 editions
New thermal elements | Retained thermal elements | |
Wall | 0.28 W/(m^2K) | |
Pitched roof – insulation at ceiling level | 0.16 W/(m^2K) | 0.16 W/(m^2K) |
Pitched roof – insulation at rafter level | 0.18 W/(m^2K) | 0.18 W/(m^2K) |
Flat roof or roof with integral insulation | 0.18 W/(m^2K) | 0.18 W/(m^2K) |
Floors | 0.22 W/(m^2K) | 0.25 W/(m^2K) |
Swimming Pool basin | 0.25 W/(m^2K) | |
Wall – cavity insulation | 0.55 W/(m^2K) | |
Wall – external or internal insulation | 0.30 W/(m^2K) |
NB Approved Document C gives limiting values for individual elements to minimise the risk of condensation.
[edit] Related articles on Designing Buildings Wiki
- 2013 changes to the approved documents for part L of the building regulations
- Approved documents.
- Building Regulations.
- PA ratio.
- Part L.
- U-value.
[edit] External references
- Approved Document L1A: Conservation of fuel and power in new dwellings, 2013 edition.
- Approved Document L2A: Conservation of fuel and power in new buildings other than dwellings, 2013 edition.
Featured articles and news
Quality Planning for Micro and Small to Medium Sized Enterprises
A CIOB Academy Technical Information sheet.
A briefing on fall protection systems for designers
A legal requirement and an ethical must.
CIOB Ireland launches manifesto for 2024 General Election
A vision for a sustainable, high-quality built environment that benefits all members of society.
Local leaders gain new powers to support local high streets
High Street Rental Auctions to be introduced from December.
Infrastructure sector posts second gain for October
With a boost for housebuilder and commercial developer contract awards.
Sustainable construction design teams survey
Shaping the Future of Sustainable Design: Your Voice Matters.
COP29; impacts of construction and updates
Amid criticism, open letters and calls for reform.
The properties of conservation rooflights
Things to consider when choosing the right product.
Adapting to meet changing needs.
London Build: A festival of construction
Co-located with the London Build Fire & Security Expo.
Tasked with locating groups of 10,000 homes with opportunity.
Delivering radical reform in the UK energy market
What are the benefits, barriers and underlying principles.
Information Management Initiative IMI
Building sector-transforming capabilities in emerging technologies.
Recent study of UK households reveals chilling home truths
Poor insulation, EPC knowledge and lack of understanding as to what retrofit might offer.
Embodied Carbon in the Built Environment
Overview, regulations, detail calculations and much more.
Why the construction sector must embrace workplace mental health support
Let’s talk; more importantly now, than ever.
Ensuring the trustworthiness of AI systems
A key growth area, including impacts for construction.