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Our highland house is approx. 100 sq metres of living space and we heat it with a wood burning stove, which is also used for coking.

The test we have done was based almost entirely of burning compressed wooden bricks that weigh around 1kg each.

Normally we burn fuel for 3 or 4 hours a day which results in average indoor temperatures of 18C to 21C which we find comfortable.

For the last few weeks an illness in the family has meant that we've needed to increase the indoor temperature somewhat, so we have been burning for far longer each day.

RESULTS
All results using 1kg compressed sawdust bricks. The results are not tolly comparable as from time to time faster and hotter burning pine is added when a burst of heat is needed while cooking. But the amount of additional fuel consumed is minimal, say 1/2 basket over 3 days.

Subsistence mode: 1.5hrs per day consuming approx. 3kg
(house cold, 11 to 18C heavy clothing and hats needed indoors to keep warm)

Normal Mode: 4 hrs per day consuming approx. 6Kg
(House warm/cool, 18 to 21C light jumpers needed to stay warm)

Hot Mode: 14hrs per day consuming 10kg
(House hot 25 to 31C only t-shirts needed)

I'm pretty happy with the efficiency we're getting as it kind of reflects on the energy conservation measures we've installed. The data is very helpful in estimating our fuel stocks in various living scenarios.

I'd be interested to hear how others who are heating and cooking with wood compare?
Homesteader's reckon that four and a half cords of wood is enough for a winter ? 1 cord = 8ft longx 4ft wide x 4ft high so that equals 28 ft long x 4ft wide x 4ft high , on my Rayburn i used six cords the wood was a mix of pine,ask and oak ...i also used 2 ton of coal this ran only 3 rads hot water and cooking (to small for the whole cottage) but reasonable.... 260sq mts total floor area ...then we changed the Rayburn for a new multi fuel woodburner that would heat all the rads and hot water 125,000 btu that year saw us use 9 cords of wood (same mix ) and 4 ton of coal ....i call it monster mouth ....but there again the only time it went out was to give a good clean ...warm as toast in my Y fronts....no rads were turned off or down even the six rooms not in use ....okay its not the way we would use the system normally but i wanted to test the system full out....the upshot of the trial forced a rethink in insulation values ....and these we put to rights ....i cannot emphasize the inportance of GOOD insulation. Fuel any fuel...is expensive ....wood burners = hard work and continuous hard work at that ....most months will involve some activity towards fuel supplies , and maintenance of chimney and burner unit....the main reason for down sizing for us....and lower maintenance ALL AROUND is where we are heading.....BUT loads of ground to to grow veggies and keep hens, goats and piggies .
Can't bloody wait !
Sorry 36 ft long 4 ft wide x 4ft wide .
This winter has been very warm, and we have 90mm external wall insulation. Result ? Loads and loads of fuel left, should last for years.
same here had over 50% of last years wood left this year only just started lighting a fire over the last few weeks.
last night I got bit by a knat in jan ..... wow , more winters like this me thinks...
I should make clear ...that those figures are a year ago and are NOT current ....but a good test though...this year has been mild ...UP TO NOW that is .
That's a lot of fuel you've been consuming there SS.

It makes our consumption look very meagre by comparison, even taking into consideration our smaller footprint. Last winter we went through around 300kg of the bricks and around 1.5 cords of scots pine.

For info, our firebox is rated at 7 to 12Kw, so this will be helping with the economy. We only heat air at the moment, there are no radiators anywhere in sight.

Steve: How much difference has that external insulation made at your house? and what is the original wall construction.

Here we have approx. 3ft thick walls made of granite blocks and boulders cemented together with lyme mortar. I did toy with the idea of external insulation, but decided against in the end, feeling that the massive thermal storage of the walls would not benefit greatly from the addition.

I'm happy to report tat we started this winter with greater wood reserves than we started last, so our long term provision is improving. Over new year bevvies, my neighbour aand I agreed for me to help him with some forestry work he wants to get done in the spring, and that for this my payment will be in wood. So hopefully the wood store will be brimming very soon.
Yes LS .......extreme even.... but that quantity was over a full years use...wife was ill , so had to have it on all the time...having said that, since that time i have removed three sets of French doors ...bricked up and replaced them with Pvc u windows...plus changed six other windows, along with more insulation in the attic space and partition work with more insulation....what a difference ! that lot has made....unbelievable ....this will kill you though....we are now running on LPG gas ...to check the running costs and do the comparisons set against the wood burner...then i will revert back to wood ....when i build the new place ( money ) i will put in a rayburn (converted to oil fired ) which are more efficient ...but easy to convert back to multi fuel should the need arise ...doing the sums four cords of wood should well cover our needs...the new place will be WELL AND TRULY INSULATED .
Yes, I remembered that you were having to keep your dear lady in the warm that year.

I think the Oil fired Rayburn is an excellent idea. Why make life more difficult than it needs to be. And permanently burning wood is serious hard work. You say the Rayburn will easily convert back to multi-fuel..what amount of time and cost is involved? I ask as in the longer term this might be a useful idea to implement at our place.

Wishing you complete success with the new-build.
If you have a Rayburn (solid fuel/wood ) you can convert this to oil
burner within about six hours i am told LS ...you can switch back to solid fuel in even less time...the cuts of the fire box does not alter that much if at all...however...you cannot do this if you have a dedicated oil burning Rayburn ....you have to start with a solid fuel type.....not done this myself YET but is easy i am told ...note...LPG per ltr =45p if you tie in for 2 years.....oil per ltr 29p...plus 20% more efficient per KW hour ...what's not to like !
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