If you’re into homebrewing, you’ve probably realized how important temperature is during fermentation. The good news? You can build your own fermentation chamber without spending a fortune. In fact, with a few tools and some affordable parts, you can put one together for under $100. This guide, inspired by tips from the Learning to Homebrew blog, will help you get started.

First things first, what is a fermentation chamber and why would you want one? Basically, it’s a small space where you can control the temperature to help your beer or other fermented drinks come out tasting their best. Yeast behaves differently at different temps, and controlling that environment helps improve both flavor and quality.

To build your own chamber, the best place to start is with an old mini fridge or a free-standing freezer. Try to find one through local online marketplaces—people often give these away or sell them for cheap.

Next, you’ll need a temperature controller. These let you plug in your fridge and set the temperature to exactly what your yeast needs. One of the most popular and budget-friendly options is the Inkbird ITC-308, which costs around $35–$40.

Here’s what you'll need:

- A mini fridge or small freezer (around $30–$50 used)
- An external temperature controller ($35–$45)
- A small fan (like a computer fan or clip-on fan, $10–$15)
- Extension cords or power strip (if needed)
- Some foam or weather stripping for sealing any extra air gaps ($5 or less)

Put the fridge in a cool dry place like a garage or basement. Stick the probe from the temperature controller inside the fridge so it can monitor the air or liquid temp (you can tape it to the side of a fermenter or place it inside a bottle of water for a more stable reading). Plug the fridge into the controller, set your target temperature, and you’re in business!

The fan helps keep air moving inside the chamber, which helps keep the temperature even all around.

And that’s really all it takes. With some resourcefulness and a few supplies, you’ll be controlling fermentation temperatures like a pro—without emptying your wallet. Cheers to better brews!