How to Dry Wood Fast with a Solar Kiln

  • November 29, 2018

Let’s face it: the wood you get isn’t always dry. Wood tends to be the wettest immediately after leaving the sawmill, and if you’re getting it freshly, then there’s a good chance that it has a high moisture content. This extra moisture can make working with the wood difficult, and if you’re going to a tight fit, you need to make sure that your wood is properly dried to the lowest moisture its going to experience relative to the air, so that it doesn’t warp, expand, or shrink later and come loose.

Traditional knowledge suggests that it can take up to a year to dry a piece of lumber per inch of thickness. Yikes!

If you don’t have that long, we have some tips for how you can dry wood quickly and get on the projects that you want to do.

  1. Get a moisture meter

Drying wood fast runs the risk of drying it so fast that you cause defects. There’s also no reliable way to tell how dry lumber is, based on look or feel. Getting a moisture meter, or a device that measures how much water is present in lumber can take the guesswork out of drying wood.

moisture meter

Image credit: Juan, Flickr

There are two kinds of moisture meters.

The first is the pin meter, which can measure moisture at different depths by inserting the pins into the wood. The downside is that you have to damage the wood to get a good reading, and the reading can be inaccurate if you incorrectly insert the pins.

The second is the pinless meter, which uses an electromagnetic signal to determine how much water is still in the lumber

  1. Know your water targets

How dry does your wood need to be? Typically, softwoods need to dry to between 10% and 11% for indoor use. Hardwoods perform best at between 6.5% and 7.5 percent. How long you dry is thus going to depend on the wood type and how wet it is initially. You’ll also need to research what the safe drying speed for your lumber is. Different woods can dry at different speeds without cracking but exceeding these limits can permanently damage your wood.

  1. Build a Solar Kiln

Solar kilns are one of the most cost-effective ways of drying wood fast, and they don’t require the use of flame, which is always a tricky prospect when working with wood.

The most popular solar kin design is the Virginia Tech solar kiln, an early model on which most modern models are based.

It involves building a shed-like structure with a glass, clear polymer plastic, or fiberglass panels. The interior is insulated and painted black to maximize the amount of trapped heat. The extra heat helps cook moisture out of the wood, and most solar kilns use one or more fans to draw in fresh air and force out moisture-rich air.

solar kiln

Image credit: xiquinhosilva, Flickr

Since it’s a system that relies on being able to draw dry, or drier air in, solar kilns don’t work well when it rains or when the relative humidity is high. Since it’s solar power, it doesn’t work at night, or on overcast days.

However, with moderately-good conditions, a solar kiln can reduce wood drying times down to about a month, which is almost a 92% reduction in drying time compared to the year that it would take without.

Hopefully, these tips will help you get to drying your wood in no time flat, and have you doing the projects you want to do in just a few weeks.

About the Author Adam Harris

Hi there! My name is Adam and I write for HealthyHandyman. I have a great passion for writing about everything related to tools, home improvement, and DIY. In my spare time, I'm either fishing, playing the guitar, or spending quality time with my beloved wife. You'll also often find me in my workshop working on some new project!