Rising fuel prices and the need to cut carbon emissions has put greater focus on green building and renewable energy. Schiedel Chimney Systems’ Stephen Dodds explains why wood burning stoves are the smart as well as safe way to heat modern eco homes.
Developments in heating systems, insulation and use of appliances have made a substantial contribution to reducing the UK’s carbon dioxide emissions in recent years. Despite this, UK housing stock is still some of the worst in Europe in terms of energy efficiency, accounting for a quarter of our annual carbon emissions – as revealed in the Government’s own Housing Energy Fact File.
Failed attempts to improve housing, such as the Green Deal, have called into question the Government’s commitment to carbon reduction, but if its target of an 80 per cent reduction in carbon emissions by 2050 is to be met, it’s essential that we upgrade the energy efficiency of our homes.
The recent push for housing schemes and funding towards affordable homes has contributed to the increase for timber framed homes over the last few years, which bring about obvious cost saving, construction and sustainability benefits.
Green building is a wise choice for architects with customers who wish to future proof against rising energy costs and fuel poverty. New schemes designed to encourage self-builds are emerging, such as the Government’s Right to Build, will hopefully see an increase in eco homes and passive houses being constructed for years to come.
Low impact living
Responsibly sourced timber can provide both an environmentally friendly building material and a renewable heat source.
The popularity of timber frame building has now spread to commercial builds as well as being a mainstream method for private housing companies and self-builders.
Wood is considered a renewable fuel as carbon dioxide is absorbed as the wood grows and later released during the burning process. Some carbon emissions are produced during the production and transport phases, but wood is still one of the most climate-friendly fuels we have.
It’s not just biomass boilers that can offer renewable heat. New generations of wood burning stoves deliver hot water and central heating and are highly effective at spreading warmth through the well-insulated, open plan spaces commonly found in new builds. More than a million UK homes are already heating their homes with wood fuel according to the Stove Industry Alliance, which estimates that based on current sales of 175,000 wood burning stoves per year continuing, they could offer an annual 10 per cent reduction in UK carbon emissions – over two million tonnes.
Satisfying Part L and safety needs
New builds must comply with Part L of the Building Regulations, which focuses on energy efficiency, including
lowering carbon emissions. Modern stove models generally achieve upwards of 80 per cent efficiency – some even top 90 per cent. The carbon savings made by using wood heating can help compliance with Document L, as well as satisfying Standard Assessment Procedure (SAP) calculations – the method used by Government to assess and compare the energy and environmental performance of a dwelling.
Sustainable homes undoubtedly present additional challenges when installing a wood burning stove. New builds are becoming increasingly well insulated, for example, so any chimney products used should be designed to meet the ‘blower door test’ so as not to compromise the building’s airtightness. But, with the development of new products specifically made for this type of building, there is no reason why wood heating shouldn’t be a safe and efficient heating method.
There is a risk of chimney fire in any building using a wood burning stove, so in light of this, lining chimneys properly is highly advisable. Single wall flue penetrations through a timber frame are a particular concern, so special care must be taken. Schiedel’s Ignis Protect, for example, can be used to pass through both interior and exterior timber-frame walls up to the temperature class T600.
In order to ensure maximum safety, a standard gap of 40 mm must be kept between the outer surface of the chimney and the structural timbers, with flexible timber frame ties used to attach the chimney to the wall. Stove installation should always be carried out by a HETAS-qualified engineer who will be trained to spot all the potential safety issues with a specific type of building and give advice on what type of chimney and stove is suitable.
Wood is good for our buildings and how they are heated. As more of us strive for more natural and environmentally friendly ways to live, wood burning stoves will continue to grow in popularity, with the new breed of flues, chimneys and pass through systems, designed specifically to facilitate this relationship.
Stephen Dodds is key account manager for Schiedel Chimney Systems