On drying logs in a shed

  • Posted on: 8 February 2016
  • By: rob

I have sometimes wondered how long I need to leave sawn and chopped logs in my shed before I should burn them in my rather nice Clearview log stove. Rather than going to the trouble of buying a moisture meter, I have devised a simple log weighing experiment. I expect that if the log stops losing mass, then it is dry enough to burn.


  1. Select a small number (8) of logs as the experimental sample.
  2. Take weekly measurements of the mass of each log using digital kitchen scales with a resolution of 2g.
  3. Record the mass and date on each log to help prevent transcription errors
  4. Collate results in a Google Spreadsheet
Log G from Set A showing recorded mass and date


I got some freshly cut willow logs in June 2015. Some were sawn and chopped in June (Sample A), some more in September (Sample B). I selected 8 logs of different sizes from each batch. The logs are not required for burning in the 2015-2016 winter, so I plan to continue the measurements until winter 2016.


As of February 2016, the measurements are on-going so I can only present findings to date.

Summary of loss of mass due to drying
Sample A Sample B
Start Mass 9194g 9202g
Current Mass 6284g 7456g
% of start mass 68.4% 81.03%

The full table of data and graphs are stored in Google Drive.

Relative mass loss for set A


  • Logs contain a lot of water. If you have 100kg of fresh logs in your shed, that may be around 35 litres of water
  • When you fill a shed with fresh logs, you can expect a significant volume of water condensing on the roof. Perhaps it makes more sense to dry logs outside first if you have the space
  • Logs put on mass when the weather is not very warm, get your logs in the shed by April if you need to use them next winter
  • I want to keep tracking this set of logs to see if they lose a significant mass of water on their second summer in the shed.

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