20 November 2011
|Such a long time since I have had the desire to sit at the keyboard and bash away at some thought process that is running around my head.|
I have had more TCs piling up ready for action than I have been able to sensibly place around my workbench, bedroom set of drawers, bedroom window sill and living room table come packing time. Eutechnics work is a dominant presence at weekends as weekday activity is minimal with my ‘proper job’ taking precedence. Nevertheless other things for a warm and pleasant life are much needed and must be seen to as well. One such is a much discussed, argued about, considered, abandoned and eventually chosen woodburning stove. We are actually going to go for a multifuel option, so we can burn smokeless brickettes (or briquettes as I have seen it written, and as the spellchecker wanted to alter it) and watch as lazy flames writhe and uncoil before our eyes.
I was after a sealed unit, that is a stove that draws air in through a well defined inlet hole rather than from a series of air-trickle vents around the front, sides, top, edges, etc. Why the sealed option, I imagine you asking? (I must have a world-wide audience of at least 3 readers - so it’s you!) ‘Normal’ stoves are little more than well-mannered and contained open fires. They pull air from the room they are in and push smoke and gases up the chimney flue. Consider this... the air taken from the room is replaced from where? Cracks around windows and doors, a possible ventilation grill somewhere in the room? It must come from somewhere or the pressure inside the room reaches a point where it is too low for gases and smoke to go up the chimney, there is no air displacement and the fire will smoke into the room and cause trouble. If however there are ‘leaks’ of air around the room, cold air is pulled in to run the fire, which takes all the warm air from the room, burns fuel with it and up the chimney it goes! The warm air of the room, for which the stove was installed to create, is actually pulled away to be displaced by cold.
A ‘sealed’ option means a separate 100mm air-pipe is routed to the inlet at the back of the stove and next to no air is taken from the room. The air-pipe is pathed to the outside. This is all very easy to say and even easier to imagine and plan, however it is a complete sod to do and caused more than a few problems all on its own.
Our living room is a decent size and has the fireplace off to on side. By use of a stove planning calculator on some website seen (not a clue which one now - seen too many) a 5kW output was deemed to be more than sufficient. Especially since we have layers of glass for insulation now, which have transformed the house and living room especially. It has 20 m3 of window area, which had been single glazed and had all the temperature containment of a plastic sheet. As mentioned in other blogs, we had these ripped out in glorious style and hybrid-framed triple-glazed units put in. Some heat calculations hastily scribbled in the margins of some boring book I was reading glassy eyed, seemed to show we needed more than 2kW just to maintain warmth on a freezing day. With 3G (triple-glazing geek speak) this figure dropped to 700W. I was reasonably determined that heat added to the house should not then be sucked up the chimney!
Many years ago, when I had a head of dark hair and very young children, I lived in a thatched cottage in Oxfordshire (Watchfield near Swindon). With a large and blazing fire in the open grate and smoke hurling itself up the chimney, which was a very large vertical shaft you put a Dickensian chimney sweep up without him or her getting stuck; the house itself became really cold. A howling draught started in the bedroom up in the roof space and came wafting down the stairs pulling all the heat in the house with it. An air-inlet for the fire would have worked a treat but was a low priority.
We have gone for a Franco-Belge Montfort Mk2 in charcoal-grey enamel. This will grace the fireplace that I thought I could ‘do’ in a week, removing the old stones and stonking great lump of oak lintel (decorative only I discovered). We must have removed about 1 ton of stone and concrete. The wall had been covered in thin slivers of stone to emulate a stone wall. These were so well stuck on with tile cement, it pulled off all the plaster - so even more dust and rubble!
I cement rendered the inside walls, I plastered the outer walls up to neat vertical metal edges (which took a day to nail to the wall without breaking the edges off the bricks). My greatest part of the fireplace saga was the vast slab of Yorkstone (a fine layered sandstone/grit mix) of huge weight found behind the garage and half buried in nettles and weeds. Imagine something the size of a small table top - in old dimensions almost 4 feet x 2.5 feet x 4 to 5 inches thick. It was all I could do the lift it up onto one edge and I saw it was smooth and well worn on one side and covered with a layer of tarmac. Not a clue what it had once been or where it had come from; but I knew where it was going!...
It took over an hour to walk it corner to corner to in front of the garage and a whole day to split it down the edge to make two riven pieces that could be the base of the fireplace. The riven pattern is mirror image from left to right on a centre join line - unique!
I hired a hole saw and drilled a series of 107mm holes through the side corner of the fire place, across a cupboard in the ‘back kitchen’ and then an even deeper diagonal hole through in to the old (still used) outside boiler house. The stove air will come from there.
It will all be fitted Monday. We have stacked up 2 m3 of dry-split logs in the old shed at the back of the garden - and generally will be ready to go and finish the decorating... etc etc.
Oh yes... TCs... number 185 has just arrived and must be worked on... must go.