Inglenooks

ABOVE: An inglenook was originally defined as a chimney corner but is now more commonly known in the building industry as a large fireplace with room enough for seating/storage. In a traditional context they tend to feature a thick bressumer beam.

A striking traditional fireplace is an important focal point that plays a major role in enhancing the appearance of a house of this type.

However, with the increasingly stringent requirements for the energy efficiency levels achieved by houses it has become more and more difficult for any sort of open fire to conform with the section of the Building Regulations that deals with fuel and power — Part L. This is especially so in the case of fireplaces that have big chimneys, through which air can escape in large quantities.

Since April 2006 the means by which the SAP (Standard Assessment Procedure) rating on your new house is calculated has changed. It is now calculated on a ‘whole house’ basis and the key issue is how much carbon dioxide your house emits. Many selfbuilders who wish to install a traditional open fire believe that the effect of the changes has been to reduce choice. However, this is not necessarily the case.

There has, nevertheless, been a major move towards enclosed stoves in large fireplace openings in new houses. This is because your house is far more likely to achieve the required SAP rating with an enclosed stove as opposed to an open fire in an inglenook fireplace. The reason is that stoves offer much more control over the burning process, and suck in far less air. This means that less heat goes up the chimney, plus they do not encourage draughts in the way open fires do. If you burn wood from sustainable sources, which is largely carbon neutral, then you will also gain in terms of the overall SAP rating.

However, because the SAP calculation is now taken from all the elements of the house – all of which have a carbon emissions rating – the designer in some ways has greater flexibility. The key thing is that if you intend to have a large open fire you should make absolutely certain that it is designed into your whole house carbon emissions calculation at the design stage. This is the advice of Stuart Fairlie of Elmhurst Energy Systems, one of three companies approved to supply the carbon emissions software to the government.

“We get a large number of calls from people on this issue, and we explain that the intention of this section of the building regulations is not to stop large open fires altogether but just to carry out a balancing act to ensure the whole house conforms,” Stuart says.

However, because of the heat loss though large chimneys, if you intend to burn any fuel other than wood on an open fire in a large inglenook with a very big chimney, then you are likely to have to compensate highly for this in other areas of your self-build. Apart from very high levels of insulation, you may find that in order to comply you might have to take further measures such as installing solar water heating, and possibly even a ground source heat pump, or perhaps a combined heat and power system. It is a high price to pay for the pleasure of having a large traditional open fire. You are unlikely to have to compensate quite so drastically if you opt for an open fire with a modern convector box.

ABOVE: There has been a definite move towards enclosed stoves in inglenooks in recent years as a house is far more likely to achieve the required SAP rating with a stove than with an open fire

The same applies to woodburning appliances. If you are prepared to install an open woodburning appliance with a damper and convector box, and make sure it is specifically classed as a ‘secondary’ means of heating that burns wood from renewable sources, you might find you comply without having to take large compensatory measures. This is because wood gains far more ‘carbon credits’ than the usual secondary heating source, electricity.

The other important thing, according to Robert Burke of the Chimney Development Association, is to make sure the gather at the bottom of your lined flue has an opening that suits the appliance you are intending to install. Doing this will make it far easier to comply with the regulations.

A final means of making sure you comply is to create a large inglenook opening, but restrict the air intake by installing just one small flue at the rear. “A lot of people who want open fires are taking this course,” Robert Burke says. “This is because if you install a small convector open fire at the rear of the opening you will achieve much the same appearance, but the installation will be much more efficient.”

Further reading:

• Converting an 18th Century Stone Barn
• Making Ends Meet
• Extending a Listed Cottage