When considering glass the Building Regulations are set to ensure that the application and use of glass in any number of building scenarios is safe and/or energy efficient. Wherever glass is used in building, whether it’s a new construction, refurbishment or basic glazing replacement the way that glass is manufactured, supplied and installed must comply with Building Regulations. There are many different building regulation parts to adhere to which define the right glass and glazing for its given intention. Ensuring that the right glass is used is the responsibility of the end user, for instance having your windows replaced in your home means that the glazing must comply with many building regulation requirements, ensuring safety where applicable and energy efficiency, ensuring building control are informed of the change is vital and should be kept on record to identify that compliance is met if you decide to sell or move on from your home. Insufficient evidence of Building Regulation compliance could leave you in a difficult position when it comes to selling your house.
Navigating these Building Regulation documents can be daunting to say the least, below you can follow links to the most up to date documents, as well as guidance regarding the specification of glass and glazing in buildings and what current levels of compliance you are required to meet for your home or project.
Which documents apply to where?
Building Regulations apply to all countries in the UK & Ireland, however the responsibility for these regulations differ between countries, for instance in England Communities and Local Government are responsible for Building Regulations where as in Scotland they have the Scottish Executive who regulate the requirements through the Scottish Building Standards Agency. For the main part, the current performance requirements in England, Ireland, Scotland and Wales are the same, however this looks destined to change, based on the response to recent regulation consultations. To find out which document applies to which country you can download the literature from the bottom of the page.
Here you will find links to the approved documents for each country:
England - Communities and Local Government
Wales - Welsh Government Approved Documents
Scotland - Scottish Executive, Scottish Building Standards Agency - New 1st October 2015
Northern Ireland - Building Control
Republic of Ireland - Department of the Environment, Heritage & Local Government
Overview of performance requirements relating to glass & glazing
Below we have provided links to download the most up to date Approved Building Regulation Documents for England along with a short summary to advise how they effect the glass used in application. These summaries are very similar to the requirements throughout the UK & Ireland, however approved documents do vary slightly from country to country so it is always best to check that the performance indicated below meets the requirements of the country your home or project is required to comply with. Links to all of the approved documents for the different countries can be found earlier on this page.
NEW Document Q - Security - New Build Dwellings
This new regulation applies only in relation to new dwellings and provides that reasonable provision must be made to resist unauthorised access to any dwelling; and any part of a building from which easy access can be gained from outside.
Document Q - Effective from 1st October 2015
This approved document takes effect on 1 October 2015 for use in England. It does not apply to work started before 1 October 2015, or work subject to a building notice, full plans application or initial notice submitted before that date provided the work is started on site before 1 October 2016.
Windows should be manufactured to a design that has been shown by test to meet the security requirements of British Standards publication PAS 24:2012, which states a P1a category of resistance classified laminated glass, manufactured in accordance with EN 356 - Glass in building - Security glazing - Testing and classification of resistance against manual attack, should be used in any window or door on ground floor level or in easy to access area's such as first floor windows which can be accessed by flat roof's or other means.
Today, there are no 6.4 (3.3.1) laminated glass options which comply with P1a testing other than acoustic laminate. As such, the most common glass used to comply with Document Q includes, but is not limited to, 6.8 (3.3.2) Laminated glass manufactured in accordance with EN 356. This laminated glass should be certified to achieve the P2a category of resistance which exceeds the P1a classification. All Guardian Laminated Glass in manufactured in accordance with EN 356, test certificates such as our P2a classification for 6.8 Laminated glass can be downloaded from the Guardian Plus Techncial Centre
Document K 2013 - Protection from falling, collision and impact
The 2013 edition of Document K has been updated to amalgamate Document N: Glazing - safety in relation to impact, opening and cleaning, together with some guidance contained within Document M: Access to and use of buildings. Document K now details considerations regarding stairs, ladders and ramps, protection from falling, protection against impact with glazing, additional provisions for glazing in buildings other than dwellings and protection against impact from and trapping by doors. This version of Document K is for use in England only.
Document L 2013 - Conservation of fuel and power
This details the glass performance required to meet minimum targets for energy conservation. The impact of this document determines the type of glass used in building and the calculation method to identify this performance. Document L is divided into four parts:
Part L1a 2010 – New Dwellings (New Build Residential)
Part L1a refers to a minimum U value performance for windows of 2.0 W/m2K, however this is used mainly to allow flexibility in design and reduce the likelihood of condensation build up on glass. The target here is a 25% improvement over the 2006 Building Regulation Document L requirement and uses SAP 2009 as the calculation method to confirm this improvement is achieved on any new dwellings. In the majority of cases SAP will require a much lower window U value to meet the 25% improvement than the back stop value of 2.0 W/m2K. This document also takes solar heat gains (g value) into consideration, to avoid overheating in new dwellings due to solar radiation in this case High Performance or very neutral High Selective glass is commonly used to meet these requirements.
NEW Part L1a 2013 - Effective from 6th April 2014
The revision to Part L1a has now been published and takes effect from 6th April 2014. This new specification has been strengthened to deliver a 6% improvement across new home builds relative to the previous 2010 Part L1a specification. The calculation method to be used will be the new SAP 2012. The limiting fabric parameters for glazing and window performance remain the same as 2010 at 2.0 W/m2K to allow for design flexibility, however the 'Model Design' specified in Part L1a recommends a whole window U value of 1.4 W/m2K with a g value up to 63% to avoid overheating, this performance is easily achieved by using ClimaGuard A 1.0 or by using one of our SunGuard SuperNeutral or eXtra Selective glass options. Other glass performances can be used, however the Design Model recommends a notional specification that will achieve the new performance requirement. The final change to Part L1a which can impact glazing is the procedure for compliance; to ensure the design specification is achieved in the final build, the standardised report produced to verify performance must be submitted both before work commences and then again after completion with any specification changes declared. This is aimed to ensure that the 'as designed' specification is actually achieved once the building is built.
Part L1b 2010 – Existing dwellings (Replacement & Refurbishment Residential)
Part L1b refers to the replacement of glazing in existing residential buildings. The minimum required performance for replacement glazing is either a whole window U value of 1.6 W/m2K or a Window Energy Rating band C (Window Energy Ratings can be issued by BFRC, Certass or BSI), there are special circumstances where a centre pane U value of 1.2 W/m2K can be used, however this is only for hard to treat area's where the required performance values are not an option. Part L1b also advises that conservatories less than 30m2 are exempt so long as the dividing wall and door are maintained between conservatory and living space also the heating system must not be extended into the conservatory. Conservatories over 30m2 or with extended heating systems / removed dividing wall and door, must meet a whole window U value of 1.6 W/m2K. Other area's such as porches or carport, where the area is separated from the main living space are also exempt. Low E glass is commonly used to achieve the requirements of Part L1b, and ClimaGuard A+ is specifically designed to achieve the optimum performance in Window Energy Ratings.
NEW Part L1b 2013 - Effective from 6th April 2014
The revision to Part L1b has now been published and takes effect from the 6th April 2014. The changes made to Part L1b do not impact the performance specification for windows and glazing which will remain the same as 2010.
Part L2a 2010 – New buildings other than dwellings (New Build Commercial Projects)
Part L2b refers to the minimum U value performance for windows of 2.2 W/m2K, however this is used mainly to allow flexibility in design and reduce the risk of condensation forming on internal glazing. The target here is to achieve a 25% improvement over the 2006 Building Regulation Document L level and Part L2a specifiers the use of either SBEM or SAP 2009 to calculate the energy performance of the building and ensure the target performance improvement of 25% is achieved. In the majority of cases both SBEM and SAP 2009 will require a much better performance of glazing to achieve the target than the back stop value of 2.2 W/m2K. This document also takes into consideration the adverse effects of solar heat gain (g value) and Solar Control, High Performance or High Selective glass is often used to help reduce solar heat gains and avoid mechanical cooling.
NEW Part L2a 2013 - Effective from 6th April 2014
The revision to Part L2a has now been published and takes effect from 6th April 2014. This new specification has been strengthened to deliver a 9% improvement across new non-domestic building relative to the previous 2010 Part L2a specification. Calculation methods available are SAP 2012, SBEM or any other software tool approved for use under the National Calculation Methodology (NCM). The limiting fabric parameters for glazing and window performance remain the same as 2010 at 2.2 W/m2K to allow for design flexibility, however the 'Model Design' specified in Part L2a recommends a whole window U value of 1.6 W/m2K with a g value up to 40% to avoid overheating, the Model Design also recommends a light transmission of 71% to reduce the need for artificial lighting during daylight hours. This performance can be achieved by using our SunGuard SuperNeutral SN70/37. However, the Model Design is a notional building specification prepared as a guide, which if followed will achieve compliance with the New Part L2a. As this is only a notional building specification other glass performances can be used as long as the overall building specification shows a 9% improvement over Part L2a 2010. Other products which will achieve the new performance requirement are SunGuard SuperNeutral range and SunGuard eXtra Selective range. The final change to Part L2a which can impact glazing is the procedure for compliance; to ensure the design specification is achieved in the final build, the standardised report produced to verify performance must be submitted both before work commences and then again after completion with any specification changes declared. This is aimed to ensure that the 'as designed' specification is actually achieved once the building is built.
Part L2b 2010 – Existing buildings other than dwellings (Replacement & Refurbishment Commercial)
Part L2b refers to the replacement of glazing in existing commercial buildings. The minimum requirement for replacement glazing in existing commercial building is a whole window U value of 1.8 W/m2K. Where an existing commercial building is domestic in style, e.g. using casement windows opposed to curtain walling, a Window Energy Rating of Band C can be used as an alternative. Where an existing commercial building is being changed to a residential building Part L1b takes over as the method of compliance with Building Regulation Document L. Solar heat gain or g value is also a consideration on existing commercial buildings and one or more of the measures set out in Part L1b should be met in order to avoid over heating due to solar radiation and a consequential requirement for mechanical cooling. High Performance and High Selective glass is commonly used to meet these requirements.
NEW Part L2b 2013 - Effective from 6th April 2014
The revision to Part L2b has now been published and takes effect from the 6th April 2014. The changes made to Part L1b do not impact the performance specification for windows and glazing which will remain the same as 2010.
This page was last updated Thursday 5th November 2015