4 Comfort

Accreditation – sampling and testing laboratories - KBCN1337

Accreditation of organisations performing laboratory analysis and testing of emissions: NC 2016 or newer All organisations conducting indoor air analysis or emissions testing of building products must be accredited to ISO/IEC 17025, with specific accreditation covering all applicable chemical analysis and emission testing methods relevant to their scope. The accreditation must be carried out: either

By a national accreditation body e.g. UKAS.
By an accreditation body that is a signatory to the ILAC Mutual Recognition Arrangement (ILAC MRA).

Accreditation of organisations performing sampling: If sampling and analysis is carried out by two separate organisations, then sampling organisation does not need to be accredited to the above. However, they must provide a brief report justifying:

The sampling methodology used.
Appropriate environmental conditions during the sampling.
The number and location of samples taken

This report is provided to the BREEAM assessor and submitted as supporting evidence for this issue

06-May-2025 Comprehensively updated to clarify the requirements.
31-Oct-2022 Wording clarified. Scheme applicability updated.
10-Oct-2022 Title amended for clarity. Scheme applicability updated.
24-May-2022 Updated to differentiate between sampling and analysis requirements. 
07-May-2021 Added clarification regarding alternative qualifications. 
10-May-2021 Updated scheme applicability.

Communal ventilation system - KBCN1388

A communal ventilation system is acceptable as long as it meets the requirements in the HQM manual. In terms of maintenance, if it is not possible for the home occupants to carry out system maintenance themselves due to the type of system installed we would need a statement from the professional designing the system stating this. Instead, any specified ventilation system requiring maintenance must be designed to allow building services engineers to easily complete the work in a safe manner in accordance with manufacturer’s instructions and any other safety regulations, to prevent systems becoming redundant or being unable to function to their designed intention.

Compliant test body – alternative compliance route using a Suitably Qualified Acoustician - KBCN1412

Where acoustic testing and measurement has not been performed by an organisation or individual that meets the definition of a compliant test body, compliance with this requirement can still be demonstrated where a Suitably Qualified Acoustician has reviewed the relevant test report(s). The test report must: a) Be countersigned or authorised by a Suitably Qualified Acoustician b) Include a clear statement that the acoustic testing and measurements have been carried out in accordance with the BREEAM or HQM testing requirements AND c) Include evidence that the verifier meets the definition for a Suitably Qualified Acoustician within the relevant BREEAM or HQM technical manual

Emissions from products – Building materials for M&E purposes - KBCN1740

All M&E materials are excluded from VOC assessment requirements. However, from V7 onward, while finished M&E products may be excluded, all on-site applications of paints, coatings, adhesives and sealants used for M&E purposes must be included in VOC assessments under their relevant material categories.

02 July 2025 - Inclusion of duct insulation removed

Emissions from products – scope of assessment - KBCN0212

General This issue covers any product installed or applied inside the inner surface of the building’s infiltration, vapour or waterproof membrane. Where this membrane is not present, it applies to the inside of the building envelope’s interior-facing thermal insulation layer. Only products that are installed or applied in parts of the building where their emissions are likely to affect indoor air quality need to be assessed. Paints and coatings Any decorative paints and varnishes that occupants are exposed to should be assessed. This is likely to include paints and coatings applied to walls, ceilings, floors, doors, etc. Whole products A finish applied to a product in the factory is assessed as a whole product, and not separately as a paint or coating. For instance, a wood panel has a finish applied in the factory. The whole panel, including all the elements that make up that panel, would need to comply with the requirements set for wood panel products in this issue. The finished product as a whole must meet the performance requirements / emission limits set in the manual.

11-Oct-2022 - Title amended for clarity and consistency. Content merged with KBCN0871.
10-Oct-2022 - Wording simplified. Scheme applicability updated.
16-Jun-2017 - Title and general principle amended to extend the applicability of the KBCN to all finishes. Paints specified for specialist applications covered in KBCN0872.

Emissions from products – specialist paints and coatings - KBCN0872

Where a paint or coating falls within:

A category in Annex II of the EU Directive 2004/42/CE or,
A category in the relevant product emission table of the technical manual,

then the paint or coating must be assessed. Specialist paints and coatings are exempted from meeting the VOC content and emission limits where there are no alternative products available that can perform the function, and still meet the emission limits. This must be clearly evidenced.

02-Oct-2025 Reference to 'VOC content' added and KBCN applied to UKNC V7 and INC V7 to clarify CN2.1 
27-Oct-2022 Wording clarified. New compliance principle added from UKNC V6.
10-Oct-2022 Title amended for clarity. Scheme applicability updated.
13-Mar-2020 KBCN amended to clarify exceptions and applicability.
16-Jun-2017 Content merged with KBCN0212.

Erratum – Minimising airborne TVOCs (total volatile organic compounds) from all sources - KBCN1397

The benchmark for 4.1 Criterion 10 should reads as follows: The TVOC concentration in indoor air is measured post construction (but pre-occupancy) and does not exceed 0.5 mg/m³ (500 µg/m³), averaged over 8 hours.⁽⁴¹⁾ Reference 41, HM Government Approved Document F Ventilation 2010, sets a lower threshold, however for the purposes of HQM One, the threshold stated above is correct. This will be corrected in the next reissue of the technical manual.

Erratum- Representative sampling of indoor air - KBCN1645

There is a discrepancy in the manual within the methodology section ‘Representative sampling of indoor air’. Please refer to the below instead: Sample of indoor air principles

Representative sampling of indoor air is permitted where multiple homes on a site incorporate the same building products or material specification.
Different home ‘groups’ found on site must be covered by the representative indoor air quality tests, the different ‘groups’ are distinguished by the size, type, layout or location of homes on a site. For example, 1-bed apartment, 2-bed mid-terrace, 3-bed semi-detached, or 4-bed detached must each be representatively sampled.
The sample size should be sufficiently large to demonstrate consistent performance across groups of homes.

Sample strategy for developments The sample size can be modified to suit the developments specific environment and design if recommended by the accredited organisation undertaking the sampling. In this case a suitable sampling strategy must be produced that outlines the different groups outlined above, the rate of sampling per group type and how the sampling strategy still meets the intended requirements of the issue. Justification for the sample group types The Formaldehyde and TVOC concentrations are predominantly influenced by emissions from internal finishes and fittings. The concentrations of the emissions will depend on the source volume, the source rate, the room volume and the ventilation rate. This can be different based on size, type and layout of the building. In addition, the location of the homes should be taken into account as post-construction testing can be influenced by when the home was completed, with homes finished first having a lower emission rate, by external emission factors such as proximity to a road and a variety in ventilation strategies for homes in different locations such as in a high rise building.

This will be corrected in the next reissue of the technical manual.

GN22 Recognised schemes for emissions from construction products - KBCN0719

Latest version: v3.0, January 2025 Within the Health and Wellbeing category of several BREEAM schemes, credits are awarded for specifying materials that minimise emissions from building products of formaldehyde and volatile organic compounds (VOCs). The criteria involve meeting emission level performance requirements in accordance with compliant performance and testing standards. Guidance Note 22 (GN22) lists schemes that show equivalent or better performance than the current BREEAM and HQM criteria, and therefore can be used to demonstrate compliance with the criteria. This document should be read in conjunction with the relevant assessment issue guidance provided in the appropriate BREEAM or HQM technical manual. The guidance note contains two tables:

Table 1 is for use with BREEAM schemes that were first released before December 2015.
Table 2 is for use with BREEAM (and HQM) schemes that were first released from December 2015 onwards (post-November 2015).

Download Guidance Note 22 View all Guidance Notes on BREEAM Projects (licensed assessors only) Applying for inclusion in GN22 The list of approved schemes is based on those which have made a successful application to BREEAM. As such, there may be other operational schemes that could potentially be recognised. To be considered for inclusion, the scheme operator must complete an application form, providing full details of the scheme, and submit this to BRE Global for technical approval. A flat rate charge is payable to cover the costs of administering and reviewing the application. GN22 will be updated following the approval of any schemes via this process. The application form (BF1648) provides full details of the application process, and licensed BREEAM assessors can request a copy by submitting a technical query using the webform. Other parties may request a copy by contacting: [email protected]

25-Sep-2025 - Updated to provide details of the approval process and title updated.
30-Jan-2025 - Updated for release of GN22 3.0
30-Sep-2024 - Updated for release of GN22 2.9
01-Feb-2024 - Updated for release of GN22 2.8
31-Jan-2023 - Updated for release of GN22 2.7
10-Oct-2022 - This KBCN merged with KBCN0646. Title amended to align with standard KBCN naming format for clarity and consistency. Made applicable to UK and International NC V6.
25-Jan-2019 - Link to Guidance Note updated
12-Mar-2018 - Link to Guidance Note updated

Minimum ventilation rate above boost flow rate - KBCN1364

Where a ventilation system has the capacity to meet the minimum ventilation rate (Criteria '03 Ventilation rates') and where this is above the boost flow rate, then the boost flow rate can be deemed to have been met by default.

Post-construction measurement- TVOC concentration using BS ISO 16000-6: 2021 VOCs in air by active sampling - KBCN1642

Where BS ISO 16000-6: 2021 VOCs in air by active sampling is used, the TVOC concentration measurement can be performed over a 40-60 minute period.

Robust Details – 01 Sound insulation between homes - KBCN1517

Due to HQM credit entitlements being unavailable for Robust Details wall and floor types, this route can no longer be used to demonstrate compliance with crit. 1

Sound Insulation between rooms - KBCN1114

Testing between rooms cannot be carried out in–situ for the purposes of HQM. Software calculations are not acceptable either. Lab testing must be carried out as required by Part E of the building regulations (which also does not allow in-situ testing or software calculations).

Sound Insulation testing for Cupboards - KBCN1299

A cupboard (even built in) does not constitute a room and does not need to be assessed for the 'Sound insulation levels for internal walls and floors' credits as it is not permanent (part of the home's fabric) and also non-habitable.

Sound testing between rooms - KBCN1303

Only lab tests carried out in accordance with Part E of the building regulations are accepted as evidence to show compliance with the requirements sound insulation between rooms ( 02 Sound insulation levels for internal walls and floors - HQM ONE). In-situ testing and software calculations are not acceptable ways of showing compliance.

Ventilation air intakes CIBSE TM21 compliance - KBCN0669

As TM21 largely contains general guidance, rather that strict rules, it is expected that the designer or services engineer would be familiar with the requirements within TM21 and be able to determine which sections are relevant for the development in question. The main areas to consider in relation to TM21 are: • Provision of filtration • Positioning inlets to minimise impacts of traffic pollution • Positioning inlets to minimise impacts of other local sources of pollution • Positioning inlets to minimise recirculation from ventilation exhausts Confirmation is required that each of these items (and anything else the designer/engineer deems relevant) has been considered in determining the location of air intakes. Suitable evidence may for example be in the form of a short report with diagrams indicating the proposed location of intakes, with respect to sources of pollution and with reference to the relevant parts of TM21.

VOC product emission certificates – validity - KBCN1689

Where it can be demonstrated that construction product emission certificates were valid either at the time of specification, or at time of purchase, they may contribute to awarding credits.

BREEAM is primarily trying to encourage designers to take construction product emissions into consideration when specifying or selecting products and as such it is not necessary for certification to be valid at the time of design or post-construction stage submissions.

UKNC: Residential (HQM) / HQM ONE / B My Home /