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RIGHT Image courtesy of Professor Stephen Holgate Clinical Professor of Immunopharmacology, Medical Research Council. This image was part of a presentation given by Professor Holgate at the Alliance for Sustainable Building Products (ASBP) Healthy Buildings Conference, 2018 . Professor Holgate is chair of the Royal College of Physicians (RCP) and Royal College of Paediatrics and Child Health (RCPCH) working party on air pollution and a co-author of the Every Breath we Take and Better homes, better air, better health publications.

Compared with synthetic insulation materials, natural insulation including cellulose and wood fibre insulation has a much higher density. This higher density means that natural insulation makes for a better heat buffer it is the issue of penetrating heat where the thermal mass of natural insulation systems can delay the arrival of this heat energy to the internal surface, a process that can be measured and designed for known as phase shift or decrement delay. This measure can be used to design buildings that resist the transfer of heat, but be aware it is NOT a requirement in the building regulations. Breathability A breathable structure is one that allows the passage/transfer of moisture. Natural fibres constantly adjust humidity levels away from extremes of damp and dryness helping maintain air moisture at comfortable levels, reducing the risk of both surface condensation and the negative health risks from moulds, mites and viruses. Of course, fabric breathability is not an alternative to a good ventilation strategy but should be considered as part of a robust and healthy building strategy. It is relatively easy to see and to cost the damage done to buildings where moisture imbalance occurs. It is estimated that perhaps 70 to 80% of all building damage is due to excessive or trapped moisture’ With such a large percentage of all building construction problems associated with water in some way, breathability is an essential component in preventing the accumulation of harmful water being trapped within the building’s fabric. This is fundamental in reducing health risks from mould and mites that those suffering from respiratory illnesses such as asthma and chronic obstructive pulmonary disease (COPD) are particularly susceptible to. Natural fibre insulation is most effective as it suppresses potentially harmful water by binding and releasing moisture which helps regulate humidity levels as the moisture moves.

Creating and maintaining a healthy and comfortable indoor environment is a complex and difficult challenge. Temperature, humidity and carbon dioxide (CO2) must be maintained at safe and comfortable levels. Moreover, the introduction of pollutants such as particulates and volatile organic compounds (VOCs) greatly influences indoor air quality. A robust ventilation strategy is clearly critical to CO2 levels, but the building fabric can play an important role in helping to manage temperature, humidity and pollution levels.

Easy-to-fit How insulation is fitted into or onto the building also has an impact on performance, poorly fitted insulation will allow the passage of air through the structure which can quickly strip out the heat from a building. Tests by Paul Jennings from Aldas featured in the documentary The Future of Housing demonstrated that a building with an air change of 9 m3/hour/m2 @ 50 pascals (Building Regs stipulates 10) when subject to a modest 20 miles/hr wind will take just 7 minutes to remove the heat from the building, what this shows is that regulatory compliance is not a good indicator of building efficiency, a guarantee of lower bills or occupant comfort. Minimising air movement through insulation is helped if insulation is designed to help restrict airflow, features such as tongue and groove profiles and dense fibre friction fit batts help to eliminate and reduce air pathways through the building. Indoor air and occupant health Creating and maintaining a healthy and comfortable indoor environment is a complex and difficult challenge. Temperature, humidity and carbon dioxide (CO2) must be maintained at safe and comfortable levels. Moreover, the introduction of pollutants such as particulates and volatile organic compounds (VOCs) greatly influences indoor air quality.

A robust ventilation strategy is clearly critical to CO2 levels, but the building fabric can play an important role in helping to manage temperature, humidity and pollution levels. Sheep’s wool insulation, in particular, can mitigate and absorb harmful indoor emissions including formaldehyde; the high levels of Keratin based in sheep’s wool are known to react and eliminate formaldehyde test results[ii] showed that Thermafleece sheep’s wool insulation absorbed 90mg formaldehyde per 1kg of insulation. Cancelling out the noise for a peaceful night’s sleep The higher density of natural insulations - such as wood fibre makes them ideal for reducing noise. Sounds external to the building, such as traffic or music, as well as those from within the building, through walls and ceilings are attenuated better by wood fibre than synthetic equivalents. In providing better protection from acoustic pollutants, occupants often report a building as being more restful and relaxing thereby encouraging better mental health.

Web: www.ecomerchant.co.uk

RRNews - Issue 38

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Profile for Lapthorn Media

Refurb Renovation News Issue 38  

Refurb Renovation News is the UK's leading product magazine designed as a useful tool for professional specifiers and buyers who are involve...

Refurb Renovation News Issue 38  

Refurb Renovation News is the UK's leading product magazine designed as a useful tool for professional specifiers and buyers who are involve...