Chimneys fit for Father Christmas

Anyone with young children will more than likely have been issued with a list of gifts their offspring are hoping to find in their stockings on Christmas Day. Having perused the list, you may be wondering how some items on the list of requirements will fit neatly into a sock, pillowcase, or stocking as they may be too large to do so. But as well as that conundrum, there may be a more pressing issue. Will Father Christmas be able to inch his way down the chimney in one piece and without getting dirty in the process?

While you may have a beautiful fireplace and mantelpiece, decorated to perfection, the same may not be true of what lies above in the chimney.

Even if you are not expecting a visit from the great man, a roaring fire on Christmas Day really does evoke the spirit and cosiness of the festive season, so it would be wise to make sure not only is it in full working order but it is also clean – you don’t want a load of soot billowing into the room to ruin not only the mood but also anything it covers.

Fireplaces and chimney flues themselves are carefully created – it’s not just a case of banging a hole in the wall and stuffing a pipe up through the roof. The fire opening needs to be carefully sculpted to stop the smoke and fumes from escaping into the room, then persuading it to rush up the flue. The flue also needs to be constructed to speed the passage of the smoke out to the top, stopping any rain from dropping onto the fire yet preventing the dreaded ‘down draught’. The idea is not to have the great square baronial fireplace and a big square tube straight out to the roof, but a small fire opening which gathers together into a narrow entry at the top. This way the hot smoke and fumes will accelerate as they rise out of the fireplace. Once into the flue, the smoke does a couple of nifty turns around shallow bends. This stops the rain from dropping straight into the fire. Finally, it escapes to the outside through a chimney stack which must be built high above the line of any wind blowing across the roof, as this could push the smoke back down, as a down draught.

Very old flues were sculpted out of the stone stack to form the pipe. This was not a good idea because the smoke and fumes eroded the soft stone, making the inside of the flue uneven. The uneven sides slowed down the smoke, causing it to billow out of the fireplace at the bottom when it hit the slow traffic jam in the middle. Later forms of chimneys were lined with a cement and sand mixture called parging. This is smoothly applied to the inside of the stone or brickwork and is more durable than the soft stone. These are the little bits of cement that you might find dropping down into the hearth. Modern flues are lined with clay pipes, made from the same sort of clay as roof tiles. These are very smooth and durable. Where you have a gas-fired back boiler you could have a stainless steel flue.

So what about our hoped for visitor on Christmas morning? Well, even if he isn’t coming down the chimney, you may want to enjoy an open fire in which case it’s important to have the flue swept. Regularly used flues should be swept annually. Even those used occasionally should be swept every two years. Ask your sweep to comment on the condition of the inside of the flue. They will be able to say if the deposits in the bag are mostly soot or bits of cement. In the old days with brushes, they could feel the sides of the flue and decide if the parging was missing. Clay pipelined flues require little if any maintenance but those lined in parging and 80 or more years old, may need to be relined. This is a specialist task, so it pays to get it done properly. With a clean and re-lined flue, you should see an improvement in the way the fire burns.

It will also ensure Father Christmas’s visit will be quicker and easier than ever!