Introduction HEALTHY HOMES INDOOR AIR QUALITY AND MATERIALS SELECTION TECHNICAL PAPER. March 2017

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1 HEALTHY HOMES INDOOR AIR QUALITY AND MATERIALS SELECTION TECHNICAL PAPER March 2017 Introduction People around the world spend a vast proportion of their time indoors commonly up to 90 per cent where air pollution can potentially be significantly worse than outdoors. Poor indoor air quality (IAQ) can severely impact an occupant s health and wellbeing, causing drowsiness, headaches, skin irritation through to chronic respiratory problems and cancer. It can also negatively affect the productivity, commercial and operational performance of a building s occupants. IAQ is typically defined by the concentration of formaldehyde and the sum of [total] volatile organic compound (TVOC) 1 value. Formaldehyde is treated separately because of its hazardous nature. Furthermore, it is widely used in construction products such as adhesives, plastics, paper products, plasters and cements and rubber products. 1 TVOC is defined as the sum of volatile organic compounds, sampled on Tenax TA [an absorbent polymer designed to trap VOCs from air], which elute from a non-polar or slightly polar gas chromatographic separation column between and including n-hexane and n-hexadecane (n-c6 n-c16), quantified as toluene equivalent [PREN 16516:2015. Construction Products Assessment of Release of Dangerous Substances Determination of Emissions into Indoor Air]. Each VOC included in a TVOC measurement will have particular health effects. For example: Toluene (may be fatal if swallowed and enters airways, is a highly flammable liquid and vapour, is suspected of damaging the unborn child, may cause damage to organs through prolonged or repeated exposure, causes skin irritation and may cause drowsiness or dizziness) substanceinfo/

2 Healthy Homes: Indoor air quality and material selection 2 Xylene (is a flammable liquid and vapour, is harmful in contact with skin, is harmful if inhaled and causes skin irritation) 3 Benzene (may be fatal if swallowed and enters airways, may cause genetic defects, may cause cancer, causes damage to organs through prolonged or repeated exposure, is a highly flammable liquid and vapour, causes serious eye irritation and causes skin irritation) 4 Studies have found that the median concentration of TVOCs in UK housing is 1100µg/m 3, and can indeed be much higher 5. This is well above the limits set in building standards such as The Building Research Establishment Environmental Assessment Method (BREEAM) 6 /Home Quality Mark (HQM) 7 (300µg/m 3 ) and Leadership in Environmental Excellence in Design (LEED) 8 and The WELL Building Standard 9 (500µg/m 3 ). The concentration of pollutants indoors depends on: Outdoor pollution Human activities, such as smoking, redecorating, cooking, cleaning, crafts Emissions from building fabric and contents Removal by ventilation, and Adsorption by surfaces. The source that is controllable by the architect or interior designer is the selection of building materials. Limiting the sources of contaminants is key, and a large proportion of potentially harmful airborne chemicals found indoors may be due to materials specified within the building. Therefore, by substituting lower emission products these sources can be reduced or removed. In addition, materials such as insulation, fabrics and soft furnishings, will adsorb VOCs emitted from wet finishes as they dry. VOCs can then be emitted once the building is in service. By ensuring wet finishes have dried before such materials are installed reduces the significance of this source of VOC emissions 10. This can lead to significant improvements in the quality of indoor air. UK regulatory requirements UK building regulations do not cover source control [emissions from building products] in any detail, with only a small mention in Approved Document F (ADF) 11, clause The general approach adopted in the regulation is to ensure that ventilation levels are sufficient and consequently pollutant concentrations will be acceptable. In practice, however, the intended ventilation rates are often not achieved leading to higher levels of indoor pollutants. The only guideline for performance based ventilation design that is relevant to emissions from building products is that TVOC concentrations should be less than 300 µg/m 3 in service. One of the concerns about current requirements is the lack of verification and testing for compliance on completion. This TVOC concentration requirement has rarely, if ever, been used as a design basis or been verified on completion. As the best practice industry approach appears to be moving toward controlling sources of pollution and designing for sufficient ventilation levels, it is possible that ADF will be updated in the future to reflect this. Factors such as increased air tightness standards in Approved Document L 12 and the desire to reduce energy consumption of mechanical ventilation system mean that IAQ is becoming more of an issue in new dwellings. The impact of emissions from building products, furniture, cleaning and human activities is becoming more significant, as is the need to control them. Unlike in several other European countries, the UK has no requirements for materials producers to provide any emissions classification for products sold into the UK market. Pressure from designers working on high IAQ buildings is likely to encourage manufacturers to declare the results of their emissions testing for other construction product markets and make this information available for UK projects BREEAM International New Construction Technical Manual. SD Home Quality Mark. Technical Manual. SD 232: 1.0 (Beta England) LEED v4 for HOMES DESIGN AND CONSTRUCTION. US Green Building Council The Building Regulations. Ventilation. Approved Document F. F1 Means of ventilation. October Building Regulations 2010: Approved Documents L1A. Conservation of fuel and power in new dwellings (2010 edition incorporating further 2010 amendments) (in England and in Wales: Superseded by Building Regulations 2010: Approved Documents, see Document History for further details) Department for Communities and Local Government, 2010

3 Healthy Homes: Indoor air quality and material selection 3 Voluntary Ecolabels and other National Legislation Building assessment methodologies Table 1 below demonstrates that some EU member states national legislation (for example that of France, Germany and Belgium), applies to all of the product groups listed. Ecolabels, however, are relevant to specific product groups, including the finish types given below. Table 1 could be used to identify relevant labels when developing a low emissions material strategy. Table 1 EU legislation and Ecolabel applicability to key product groups Eco Label Timber Wet applied finishes Insulation Flooring Panels Adhesives and sealants Screed EU Ecolabel û ü û ü û û û û Blue Angel ü ü ü ü ü ü û û Nordic Ecolabel ü ü û ü ü ü û û Nature plus ü ü ü ü ü ü ü û GUT û û û ü û û û û EMICODE û û û û û ü û û CARB ü ü û û û û û û French Décret ü ü ü ü ü ü ü ü AgBB ü ü ü ü ü ü ü ü Belgian Décret ü ü ü ü ü ü ü ü Metal The approaches adopted by building rating tools such as BREEAM, LEED and WELL are similar overall, but vary in the detail. Not all systems address the same materials, or have the same performance requirements. Therefore, the selection of one scheme might not represent the best practice option for a particular material. Design teams should compare the requirements for each material type across the schemes and select the approach representing best practice, or comply with wider project requirements (such as HQM or WELL). Key priorities for action The designer should focus on interior finish materials. These can have high a VOC content, and there are low VOC alternatives available. For example: Paints Flooring Timber products Adhesives & sealants Other products, such as insulation, plasterboard, metal panels generally have lower emissions, and have often not been tested against any schemes available in the UK. As they will not affect TVOC levels so significantly, and cannot be assessed, there is little point including them as key materials for action at this time. In the future, when more testing has been done, this situation is likely to change. Ecolabels Legislation ü Product group is covered by scheme û Product group is not covered by scheme

4 Healthy Homes: Indoor air quality and material selection 4 Specific design advice In order to identify materials with low VOC content and emissions, test data should be requested from construction product manufacturers. Many have already tested their products to demonstrate compliance with other European country requirements or as part of an Ecolabel assessment. A proposed approach is described below. In order for it to succeed the project client must be committed to improving IAQ, and have incorporated this requirement in the strategy and brief. The development of a best practice approach to IAQ and materials is undertaken by the design team at concept design and followed through into developed and technical design. The approach comprises two stages: Stage 1: Develop a best practice approach to IAQ and materials Establish baseline Develop evidence base for each finish material type covering content and emission potential by reviewing existing guidance Identify best in class option Identify products certified as low emissions/content under third party Ecolabel schemes or national legislation/ requirements Determine main supplier readiness For each material category select a number of mainstream potential project suppliers and obtain emissions/content data Agree project strategy Determine whether best in class option is feasible based on supplier readiness Develop achievable strategy based on this Stage 2: Assess specified materials against approach to provide project recommendations Assess materials Assess architect s material selections for each material type finish Identify opportunities Make materials substitutions to improve IAQ Incorporate requirements Update specifications and project documentation to incorporate changes Include requirements for contractors in tender documents Follow on Instigate monitoring process to check contractor specified materials compliance Post completion IAQ measurement In order to help each sub-contractor follow the project materials requirements, a materials tracking spreadsheet can be developed. In this the contractor is required to list their proposed materials and demonstrate compliance with the strategy. This needs to be backed up with a process by which the materials specified can be checked once the contractors are on site. Once the project reaches practical completion, indoor air quality measurement should be undertaken to demonstrate that the homes do indeed have good indoor air quality. The levels of TVOC and formaldehyde should be lower than HQM, LEED or WELL limits, see below: Table 2 HQM, LEED and WELL IAQ test compliance levels Test/Material type Home Quality Mark (HQM) Beta version Formaldehyde <0.1 µg/m 3 (100 μg/m 3 ), averaged over 30 minutes TVOC <0.3 µg/m 3 (300 μg/m 3 ), averaged over 8 hours. No individual compound exceeding 0.03 µg/m 3 (30 μg/m 3 ) LEEDv4 Homes The WELL Building Design and Standard v1 Construction with May addenda 9 27ppb [33µg/m 3 ] 27ppb [33µg/m 3 ] 500µg/m 3 500µg/m 3 Below are four strategies that were developed by Arup for a recent project in London. The strategy reflected the types of finishes used on the project. Clearly this will vary between projects and other strategies will need to be developed following the principles defined above. Comments on the application of the strategies and some examples of the substitutions made are given.

5 Healthy Homes: Indoor air quality and material selection 5 Paints Flooring Timber products Adhesives and sealants The four main wet finishes are listed below, with the recommended approach for each. The three main flooring finishes are listed below, with the recommended approach for each. The three main timber finishes are listed below, with the recommended approach for each. The four main adhesive and sealant types are listed below, with the recommended approach for each. Concrete and masonry sealants: VOC-free or very low VOC content Clear wood varnish: use waterborne system Paints: Water based finishes should be used wherever possible, ideally EU Ecolabel accredited or with a low VOC content, lower than the decorative paints directive Epoxy sealer: Should be water based and VOC free. Products with limited hazardous ingredients should be identified As a result of the paints requirement for EU Ecolabel compliance, a product which had 17-22g/l VOC was replaced with one with less than 10g/l. The VOC content is always given on the Materials Safety Datasheet. During the substitution process it was important to discuss the options with the architect or contractor so they could confirm that the technical performance of the alternative was equivalent. Carpet/Carpet tiles: Use a product with a GUT accreditation. It should be accredited to an Ecolabel or Ecolabels that limit the content of the products (e.g. not contain TBT or have a PVC backing) PVC: Use a product certified with Eurofins Indoor air comfort gold or with a low (<150µg/m 3 ) VOC content Wood laminate: Use a product with an A+ French Décret rating As a result of the PVC requirement for Indoor air comfort gold certification the proposed material which had an emission of <250µg/m 3 was replaced with one which had a TVOC emission of <100µg/m 3. Particleboard: Formaldehyde emissions should be well below E1 1 and ideally both VOC and formaldehyde emissions should comply with an A+ rating for the French Décret MDF: Products with are ZAF or with a French Décret rating of A+/A should be used Hardwood: Products with a French Décret rating of A+/A or equivalent emissions should be used, or those with a Blue Angel certification. Note: Fire retardant and preservative treatments should be avoided. For other timber products (e.g. doors), formaldehyde emissions should be well below the requirements for a rating of E1. For any finishes used, see guidance on wet applied finishes. For the strategy to be workable only the most widely used timber types were addressed. Timber products also proved to be the most difficult to achieve compliance because many were only tested to E1. Carpet adhesives/tile adhesives and grout: Use a product with an EC1plus EMICODE rating (or EC1 if EC1plus products not available). Where possible products with a Blue Angel accreditation as well should be used Seals around door frames: Use VOC free or low VOC products where possible Note: Few Blue Angel (content requirements) products were found available. No hazardous substances should be included in these products where possible. 1 BS EN (2005). Wood-based panels - Determination of formaldehyde release - Part 1: Formaldehyde emission by the chamber method plus relevant product standard

6 Conclusions and the way ahead Healthy Homes: Indoor air quality and material selection 6 The health and wellbeing agenda is raising the profile of good IAQ Controlling the sources of VOCs is expected to become as important as the ventilation strategy in improving IAQ The approaches adopted by building rating tools are similar overall, but vary in the detail. Not all systems address the same materials, or have the same performance requirements. Therefore, the selection of one scheme might not represent the best practice option for a particular material. Design teams should compare the requirements for each material type across the schemes and select the approach representing best practice, or complying with wider project requirements There are many low emission materials substitutions that can be made at little or no extra cost Designers requesting emissions [and content] data from product manufacturers will raise the profile of this issue and show manufacturers that providing low emission products, with test evidence will increase the likelihood of their product being specified As specifying for low VOC emissions becomes more widely practised, the avoidance of hazardous substances in product content will receive greater attention In-situ VOC sensor technology is developing and in the future will provide real time data on VOC levels in homes Acknowledgements This paper was authored by Clare Perkins, Senior Materials Scientist, Arup UK-GBC and Arup are grateful to the following organisations for their input during the development of this paper: Hodkinson Consultancy WSP Arup 13 Fitzroy Street London W1T 4BQ T: +44 (0) E: materials@arup.com W: UK Green Building Council The Building Centre 26 Store Street London WC1E 7BT T: +44 (0) E: info@ukgbc.org W: UK Green Building Council Registered charity number