Burning softwood/hardwood

Muahahaha

Im soon to order about 2 cubic metres of firewood for the winter and came across a local place that has builders/bulk bags of pine wood which is air seasoned to 15% moisture for €65 and kiln dried silver birch for €120, almost double the price. I know softwood like pine isnt as dense as hardwoods like birch so will burn quicker. But wondering how much less efficient it is, would it be 50% as the price suggests? Would you need to typically buy twice the volume of softwood over hardwood to achieve the same burning time & heat output? Ive limited storage out the back so space is a concern too.

Also if buying pine logs here would it tend to be locally grown or imported?

accidental forester

We burn through over 15m3 of a sitka/lodgepole mix per season. Yes, it burns like the clappers. It's what we have and beggars can't be choosers. There's great heat out of it (hearth mounted, 20kW boiler stove) but you will have to feed it constantly. It should go without saying that most conifers spit like crazy so are not suitable for open fires.

The the last page of the attached document from the UK Forestry Commission has one of the best comparison tables I've come across. According to it, you get about 65% energy output from, say Sitka as opposed to Birch.

I'd be surprised if there is such thing as air dried conifer down to 15% moisture. We air dry the above quantity each year. I spot check some batches by weighing the freshly split wood and checking it periodically. Over a good summer, it will get down to somewhere between 65 to 55 percent of it's wet weight and go no lower. My (admittedly cheap) meter says it's in the 22 to 18 percent moisture range.

Where possible, we should make an effort to burn locally produced firewood as opposed to shipping it in from Eastern Europe.

If link doesn't work, search for 13-07-02_FCE_SEL_Market_update.pdf

Muahahaha

Thanks AF, very helpful. Do you have any practical comparison for hardwood v soft? I know it burns faster but can you put a % on it? Like given a cubic metre of hardwood how many cubic metres of softwood do you reckon would be its equivalent.

I cant seem to find that chart of calorific values for different species, I can only get page one of it and the table is on page 8 according to another forum on firewood

This is where it should be but its coming up as 404 for me
https://www.forestry.gov.uk/pdf/13-07-02_FCE_SEL_Market_update.pdf/%24FILE/13-07-02_FCE_SEL_Market_update.pdf

Also what species would be locally grown firewood to Ireland? Mainly ash?

accidental forester

Try searching for "relative outputs from wood". There are several sites that have the info. Try for UK or EU sites as they are more likely to measure in cubic meters that the US "cords". I can't find the original source for the PDF I have. Also can't seem to attach it to my post. Feel free to pm me.
I can't really say how much more pine you'd go through over hardwood. Roughly speaking, I would think it would be 25 to 50 percent more. For good heating and convenience, a mix is ideal. If I were you, I'd get a bag of each and see how goes.

Muahahaha

Yeah the same guy is offering kiln dried silver birch for 120 a bulk bag so I think I'll get one of each and see how I find them. My only worry is the size of these bulk bags, they seem to be only about 0.6 of a cubic metre which isnt all that much.

Anyway thanks again for the help.

Kickstart1.3

Kiln dried burns hotter for longer with a lot less ash produced. Its cleaner to handle, and generally suited to those modern glass type stoves/fireplaces you'd see in the town houses