Cheap, Easy, DIY Chest Freezer to Cold Plunge

I’ve been watching all the health benefits of cold plunges. After looking at the prices however I thought there was no way I would be able to afford one especially when I’m not sure how into it I would be…I hate the cold! So I thought “How can I make this affordable on a trial basis?” After a little research I found others who too have made these at a more manageable price using chest freezers so I started there. Not only do I have limited funds but limited space so I decided to go with the most minimal plunge I could do. I want you to be able to adapt this build to fit your needs, so I’ll state the measurements needed so this will remain safe.     Although it took time looking for deal I wanted to keep this a cheap and EASY build so a sale is what I was looking for. Once started this only took about one day of work to build. Freezers on marketplace in decent condition were few and far between. Since this was a trial run I wanted to be able to use this as a regular freezer if the plunge didn’t work out so I went with a new one. I also didn’t want to make any permanent damage to the freezer just in case. I waited and watch and found one at Lowes on sale for about $179. It’s a Hotpoint 6.9-cu ft. and used mostly scrap materials from other projects around the house. It will also remain outside so exposed to weather to take that into account if you plan to do the same. Here’s how it went.

Purchased

1.      Freezer

a.      https://www.lowes.com/pd/Hotpoint-6-9-Cu-Ft-Manual-Defrost-Chest-Freezer/5002179205?cm_mmc=shp-_-c-_-prd-_-app-_-ggl-_-LIA_APP_118_Refrigerators-Freezers-_-5002179205-_-local-_-0-_-0&ds_rl=1286890&gclid=Cj0KCQjw6KunBhDxARIsAKFUGs_uiLmrEkqstt_UWlkAVCOMdEISH42ISauL-uHyRlsY-rvxkRND4XMaArHyEALw_wcB&gclsrc=aw.ds

2.      Silicone Sealer

3.      Digital Temperature Controller Thermostat

a.      Inkbird WiFi ITC-308 Digital Temperature Controller Thermostat Remote Monitoring Controlling Home Brewing Fermentation Breeding Incubation Greenhouse

b.      https://www.amazon.com/gp/product/B07PVBG8K1/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

4.      Fish Tank Filter

a.      MarineLand Magnum Polishing Internal Canister Filter, For aquariums Up To 97 Gallons, 10.5 IN

b.      https://www.amazon.com/gp/product/B01C8PH0OI/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

5.      Cedar boards

6.      1in x 2in x 8ft pressure treated pine wood x5

Scrap

1.      Scrap 2x4s

2.      Scrap deck boards

3.      Leftover House Wrap

Tools:

1.      Tape measurer

2.      Hammer

3.      Brad nail gun

4.      Circular Saw

5.      Calk Gun

Like said I wanted minimal so I started with measurements. I’m 5’6” 175lbs and my wife is even smaller so I knew if I could fit she would be able to too.  I measured myself shoulder to shoulder, sat on the floor to see how much space I would take up sitting comfortably, to determine the width and length the inside minimal would need to be and hopefully allow some extra room. Purchased the freezer got home and went to work.

Using waterproof silicon sealer with a calk gun seal any cracks where the metal comes together, all corners, metal meets the plastic top, and the drain plug. Once complete let it dry. I used clear for two reasons…I had it and clear I thought would just look nicer.

The freezers has vents on the back side as well as the right side to keep the system cool and functional. Keep this in mind. Measure the width your freezer and add 3in to 4in extra so for adequate air flow.  Then do the same for length. Using the measurements I wanted the freezer to be off the ground so rain water would not get into any components for extra safety. I used treated scrap 2x4s and cut to length and used scrap decking wood for the floor boards.

Open the freezer and from the floor board measure to the top freezer wall. Cut 2x4s to length subtracting 1.5” to put a brace 2x4 across the top to use as a “handrail” and to build strength for frame. Do this around the three sides (left, right, and rear). I didn’t close off the front because again I wanted to be able to pull the freezer out if it didn’t work out or if I had any issues. I also wanted access to the temperature control on the freezer which is located on the front. 

Now that the floor board and three wall frames are built. I wrapped this with weather proof house warp for extra security from the weather. You could probably skip this if you want to or live in dryer climates or set up where weather is not an issue.

Because I want the freezer to have no damage to it if it ends up not being a plunge I measured the lid and took three 2x1 scrap boards and cut them down to width. Then I attached three magnet bars on those pieces. The magnets is how this will attach to the freezer with no damage. Use as many as you deem necessary.

I used discounted Cedar tongue and groove boards that give this a nice look instead of just a freezer full of water on the back patio lol. I found some discounted packages at Lowes and set them up and cut to size for around the frame. If you didn’t go this route though it will save you even more. Cedar not only looks great but is naturally weather proof. I simply used brad nails to attach to the frame. Now something was still off on the look I was going for and realized it was the corners just didn’t look as nice as I would like. So I grabbed some 1”x2” and cut them down to wrap the edges of the sides as well as the lid and front panels. It took about 5 pieces of 8ft board to complete.

Once covered with cedar, add water leaving room to avoid overflow once you get in and add the temperature control unit and the filter into the plunge and let it chill and enjoy. The temp control unit will turn the freezer on and off as need to keep the temp without the water turning into a block of solid ice.

1.      When using the plunge, unplug from power to avoid a shock when using water and electricity.

2.      I started my temp at 55 degrees and worked my way down to 47 degrees.  I usually stay in about 3 to 10 minutes at a time almost every day.

a.      If you do this in the morning it will wake you up and get you ready for the day

b.      At night about 1-2hours before bed I personally have had better sleep.

c.      Do your research and try different techniques that may work better for you depending on what results you’re looking for.