When wood is cut it contains a lot of moisture. When the wood is burned, the moisture turns into tars which stick to the inside of the chimney and can catch fire.  And if it has been cut during the growing season instead of during the winter then it will be full of sap as well which makes the problem worse.  Wood should always be cut during the dormant months, preferably early winter so it can be seasoning and drying out as soon as possible.

When I first lived in Brittany, the first winter I had two piles of logs. One was just left out in the open but the other one was completely covered with a plastic sheet reaching to the ground. Not knowing any better, I was trying to protect it from the rain (and there’s a lot of rain in Brittany!).

When I came to start using the second, uncovered, log pile I was amazed to find that it was dryer and burned much better than the pile that had been covered completely.  I realised that although rain reached the surface of the wood, the wind blowing through was drying the whole pile and the rain had barely penetrated.

That was the first lesson.

Then I noticed that out in the Breton countryside every house has a log pile and that the locals cover the top of them with plastic or corrugated iron sheets to keep the heavy rain out but leave the sides open to the air.  They say that in Hollywood you can never be too rich or too thin – well in Brittany you can never have too much firewood…

Our farming neighbour Marcel had a huge pile of about thirty three metre (ten foot) lengths of tree trunks stacked behind his house.  Talking with him I learned that they were from the big storm on 1987 and he’d been steadily splitting, drying and later on burning them for over twelve years with still plenty left.  In fact he only recently split the last of them and hasn’t yet burned the last of the logs so his stack has lasted over twenty years.

How long to dry logs is something that people have strong opinions about.  People like Marcel have been using wood as a crop and source of fuel for generations so I tend to think that he is worth listening to.

His advice was that hardwoods such as oak or chestnut should be split and then kept outside for at least two years and then kept inside for another year before being burned. Soft sappy wood like pine should be avoided if  at all possible because of the extra tars, and because it burns very fast, but if you have to use it then keep outside first for at least four years so that the sap can be dried out as well as the water content.

I know not everyone will agree with this but as I said before,  he knows what he is talking about.  The length of time that Marcel was advising is the minimum and of course in practice the logs are split and put under cover in a drafty shed or lean-to and just left for years.

Marcel has a long shed running the length of an old barn, open at both ends.  He takes wood from one end and the other is filled with logs which his long-suffering son spends an hour or two splitting every sunday when he comes to visit for the traditional big family lunch. Every year or two he changes ends as he reaches the middle of the log shed.

I had some wood that was outside for over five years. It was oak in metre lengths, quite heavy when delivered.  It was amazing just how light it became after it was really dry – it felt like balsa wood and burned completely giving off a lot of heat and leaving almost no ash.