As soon as lumber has been harvested, it is green which means that is has not gone through any drying process. You can certainly expect green lumber to have a high moisture content and because of this it tends to contract and warp when it is dries. This is the reason why lumber that is being produced for commercial purposes will go through a kiln before selling it.
Kiln dried wood logs have gone through a process which was done in an environment where humidity levels and temperature are carefully monitored. It is really important to carefully monitor these factors to ensure that the wood is drying evenly and quickly which will prevent the wood from becoming warped. If it does then the wood becomes useless. The process of kiln drying the log continues until it reaches the optimal moisture content which is five to eight percent.
If you are going to buy kiln logs then you need to remember that this is not permanent. This is a common misconception among buyers. Do not forget that wood is naturally hygroscopic. This means that it has the capability to absorb the moisture that it comes into contact with. It can be the water from the rain, air humidy and even the moisture in the objects close by. And even woods that have been kiln-dried will not lose this capability. So you should never forget that the moment the kiln-dried wood will leave the premises of the lumber company where the environment is controlled to ensure it stays in its optimum state, then the moisture can change. It can change during the transportation of the wood, storing the wood in the shed or garage and even when manufacturing it.
As convenient as kiln dried logs are, they have also become really expensive. Woodworkers are now resorting to cheaper alternatives. If you happen to be one of them, then we have some great alternatives for you. You can choose to dry the green woods by yourself by air drying it. You must remember though that this will take quite some time and there is the possiblity of the wood cracking or warping even before you get the chance to use it.
Another cheaper option is to use a solar kiln. You can actually set this is up yourself and it does not cost too much. You do not need to be a genius or an expert either in order to operate one. You can look up DIY instructions online too.
If you will be kiln drying your own wood, you should never forget the importance of moisture readings. It becomes even more important for wood being dried that exceeds the one inch thickness. It is a must to record the moisture content on a daily basis to ensure that your wood is not drying too fast. For the best method to measure the moisture content, it is recommend that you moisture meter. You should also be aware of the safe rate for drying of wood depending on the species. These resources are available online so make sure that you have a copy too.