How often to sweep a chimney?

[Mentalguy2k8]

Mum's got an open fireplace, 1930-1950 semi-detached property. From what I can make out she last had it done about 5 years ago but I don't think she's had more than 3 or 4 "one-off" fires a year since - usually wood kindling with logs & a bit of coal, for a few hours max each time. She's convinced that the chimney will catch fire and won't let me light it, but there's a decent draught coming down it when the wind's blowing.

Second question, what's the best thing to burn in it, and where to buy? I've seen all kinds of woods, peat blocks, coals etc., I'm looking for something that she can just put in there and leave to get some decent heat over a few hours.

[Kenny]

Worth doing every year as it's always possible birds might try nesting in it and some wasps/bees like brickwork.

Hire the brushes from £5 - £10 a day.

[Martin Brown]

The important question is how much flammable deposit has built up inside the chimney. Hints are that you get sootfalls from time to time. Wood tars tend to be less forgiving and more inclined to catch fire if they are allowed to get excessive.

A neighbour didn't bother with a sweep for several years until they were smoked out one day in spring shortly after lighting the fire! A crows nest is another potential hazard for an infrequently used chinmey.

We have ours done about once a year which is a bit marginal with a woodburner according to my sweep but we only use it when its very cold (or we are about to run out of oil).

A real fire is always fairly high maintenance feeding and removing ash. Coal or smokeless fuel is about the best heat output per unit of bulk. You still lose a lot of heat up an open fireplace chimney though.

[damduck-egg]

Depending where she lives she may be restricted to smokeless fuels,at least to use it legally. Don't know if many people ever get done for using ordinary coal though. We keep such a fire as a back up in case of long term power cuts as it still has a simple gravity circulated back boiler that hasn't any controls that require electric. I burn plain coal. In an open fire I haven't found the extra cost of proprietary branded fuels to be worthwhile many being more suited to stoves. A 25 kg sack gives about 3 evenings of supply lighting it at

15.00 ish and still having some giving heat out towards midnight. A sack costs about £11.50 from the village shop which is not the best way to buy it but it is only the occasional bag and I can collect it with a sack truck .Some bags burn better than others which must depend on where the coal originates I suppose,but the days when Coal merchants who could offer different types from various collieries in Yorkshire or Wales etc have long gone.

Don't forget the ash removal ,if your mum is elderley it could be a chore ,I bought mine one of those ash vacs that Alidel do sometimes.

G.Harman

[John Williamson]

I was living in a smokeless zone when someone lit a fire in their newly opened fireplace for the first time in ages. The fire brigade arrived a few minutes after the first person smelt and saw the smoke from the chimney.

[Dave Liquorice]

So around 20 fires over the 5 years, or 3 weeks with a fire every day... We used to get the open fire chimney burning coal every day from first thing to bedtime when it was banked up to stay in overnight once a year.

Might be worth humouring her rather than having the argument. If naff all soot comes down you can show her and sow the seed that it doesn't need sweeping annually if it's not used...

Down? sure it's not up? I'd be a bit concerned about a down draught even in a cold chimney, particularly with a wind blowing. The venturi effect over the top tends to make a chimney draw. On still cold nights there might be a very gentle flow of cold air down but certainly not a "draught".

Others have mentioned birds nests, jackdaws are renown for building in chimneys. Can you look up and see daylight? Though I guess the standard semi construction prevents that as there will be a dog leg to get the flue from the center of the room to the base of the stack in the center of the building.

[Andy Dingley]

Sweep at least once a year, even if it hasn't been used much previously. Sweeping is as much about checking for obstructions as it is about cleaning.

Local coal merchant, they'll have something suitable for your area. Also quite cheap, compared to garage forecourts.

[Jim S]

Agreed. The tar and resins from burning wood tend to stick to the sides and are inflammable. When I had a coal/log fire I used one of those 'imps' in between (little bags of stuff that you throw on a hot fire). I assume that your mother is in a smokeless zone if she burns coal?

[Gordon Henderson]

We have a large jackdaw population in the town I live in - one year the fireplace in my office was full of flies - large houseflies coming out of the boarded up fireplace - obviously a chick had fallen down and died...

But a couple of years ago I had the fireplace opened up and a stove fitted - the chimney was quite blocked and it took the guys a while to clear it - rods to remove the debris from below, (twigs and bird bones!) then to finally push it out the top... Which at that point the skys turned black as every jackdaw in the town took to the skys in alarm!

The guys doing it said they'd never seen anything like it - I guess our house must have been their HQ... Chimneys now lined with a cowl on-top...

Gordon

[misterroy]

Sweeping is as much about checking for obstructions as it is about cleaning.

cheap, compared to garage forecourts.

if she is using the chimney so infrequently the best thing to do would be to block off the chimney, I used a fishing bouy I had, there are chimney balloons. The open chimney will be sucking her present heating out.