What's a safe distance a wooden mantel can be placed above a stove?

In the case of CE EN13229 test for inset stoves, the safe distance to combustible materials above the stove is measured and this ’shelf’ distance, which varies from model to model, should be clearly stated within the handbook that comes with your new inset stove. It may also be referenced on the stove's CE dataplate. Therefore this is the absolute minimum safe distance that any combustible mantel can be placed above that particular inset stove. However, although safe distances are tested for the sides and rear of freestanding stoves the shelf distance is not a requirement of its CE EN13240 test, simply because there would be too many variations for a standard test. This can pose a problem for the installation of stoves set within a fireplace opening.

When installing a free-standing stove within a fireplace opening, along with its connecting flue pipe, the proximity of combustible materials must always be carefully considered – this is especially true of wooden mantels, beams or shelves placed above the stove. If you've just moved house and you have inherited a stove with one of these then you should also read this article.

Some manufacturers have conducted their own safety tests to measure the safe distance above their free-standing stoves and are happy to supply the information in their handbooks. However because this is not a legal requirement most manufacturers don’t do this. To be fair to them though the problem they have is that there are just too many variables in the way that a free-standing stove can be located within the footprint of a fireplace opening, never mind the variations in the size of the opening itself and how far the mantel or beam projects from that opening. All of which may have a bearing on how the stove’s heat is radiated, convected and is likely to build up around the shelf. There’s a lot to consider…

Does the stove fit well inside the front of the fireplace or is it a rear flue installation where the stove usually sits proud of the fireplace opening so that more direct heat will be applied underneath the mantel? What is the depth of that mantel? A deeper mantel will be subject to more of the rising heat because it prevents it from safely passing it. Is there a lot of space around the stove in the fireplace so that heat can gently radiate and avoid a potential heat build-up, which could create intense heat underneath the mantel? What happens to safe distances to combustibles (including the side and rear) if the stove is overloaded and over-fired and what if the door is inadvertently left open after re-filling and the stove is also left unattended so that flames exit the fire chamber – is there a sufficient safety margin?

Over the years at The Stove Yard we've witnessed many a scorched wooden mantel where the previous installer has ignored these basic safety considerations – and we've also seen the odd one or two that have caught fire and caused serious damage.

So, how can you actually determine the safe distance?  

For years installers applied a simple rule of thumb based on the safe distances used for flue pipe and for all we know it may even have been used in the failed exmples above. Unfortunately there is no scientific basis for applying this rule to combustible mantels and as Hetas therefore no longer support this method we won't repeat it here. The view that Hetas now take is that, where the stove manufacturer has not supplied the safe distance or where there is some doubt that the safe distance may not have been derived from a valid set of tests under a wide-range of installation scenarios, then the installer is advised not to fit a combustible mantel. Where there is an existing combustible mantel or fire surround which is being retained then the installer is advised not to fit the stove unless some form of non-combustible heat shield with an air gap between it and the combustible mantel or beam is also fitted.

The differing scenarios and the lack of a unified test method mentioned above are sound reasons why many manufacturers do not recommend using combustible mantels – a safe height for one installation could easily be unsafe for another installation. An experienced Hetas or OFTEC stove installer who is on site would normally be able to take such factors into consideration and can usually be relied upon to make a safe 'belt and braces' judgement.

The safest solution   

At The Stove Yard we can offer you an excellent choice of highly convincing rustic or finished wooden’-style mantels made from non-combustible specially formulated materials which will allow you to position your 'wooden' mantel as close to the stove as you want. That way you get that great classic fireplace look without taking any risks with the safe operation of your stove. Check out our Geocast Beams here.

Click here to see a range of Geocast Non Combustible Beams