Sensory deprivation tank build

Started framing it up. Design was for tub to be 4x8 inside dimensions.

Yeah, it's a lot of framing, if I remember right the studs are spaced at less than 10" OC. But I wanted the tub to feel very solid and obviously not encounter any warping

3/4" plywood

3/4" quarter-round for the corners (shouldn't have used primed wood) and two layers of 2oz fiberglass mat. This was my first time using fiberglass and resin and it was a learning experience. One thing I learned is not to skimp on the quality or quantity of resin used. Oh, and to keep a clean work area of course which is near impossible!

and two coats of white gelcoat. All the fiberglass stuff turned out a bit more expensive than I expected but well, so does everything.

insulated the bottom for holding heat since I didn't install an under-tank heater

moved it inside, holes for bulkhead fittings drilled and pipe installed. Starting the inner enclosure. The whole outside of the tank is insulated as well, for heat and sound purposes. Standard fiberglass insulation here.

Decided to use 2x3 studs here to save cost, and it allowed me to inset the walls from the side of the tank. My dad got all this scrap "soundboard" off a job he was on, it's like a cross between cardboard and particle board. soft and light but rigid. It's the stuff they use for inside a classroom, it muffles sound and doubles as pegboard I guess. I needed a lot of sheathing for this project so I was glad to have all this stuff for free. It was used on the insides of both the inner and outer enclosure.

These are $20 transducers off Amazon, they turn any surface they are adhered to into a speaker "cone". This board works fairly well since it's light and rigid. They are mounted on the outside of the ceiling sheathing, right in front of the light. Won't be breaking any sound quality standards but the sound is surprisingly good for the amount paid and the work required. I'm driving them with a little Lepai class T amp.

Don't have a pic of the completed inner enclosure, but it was finished off with more fiberglass insulation and particle board. This pic shows the framing of the outer enclosure, the second "room" on top of the tank itself. There is about an inch to an inch and a half of space in between the two enclosures, and they do not touch. From what I understand this this is the most effective way to soundproof a space. I live on the corner of a busy street (and in a low enough income area that there are often obnoxiously loud vehicles driving by) so soundproofing was one of my main concerns.

This is the first layer of drywall on the outside of the outer room. My dad got some 5/8" firecode sheetrock off his job, which was a huge help with cost. The thicker the better for soundproofing. Some of it was 12f long which was nice, but it still turned out as a bit of a patchwork thing. No consequence, it's getting another layer! The outer enclosure got soundproofing insulation, it seemed like the material was cotton or wool or something.

Here's kind of a detail of the "room within a room" thing. This is at the door. You can also see some of the inside which is lined with FRP (fiberglass reinforced plastic) panels.

Second layer of drywall with green glue noiseproofing compound sandwiched in between. And taping, skimming, and sanding done. Dad came and helped with the taping - I swear it's my least favorite thing. So much dust.

Room cleaned up for the first time in a while. Door installed. Paint color chosen. Base and casing on. Electrical wired up.

Shot of the plumbing and filtration setup. Just a mechanical filter, a heater module for an aquarium, and pump. Plus a lot of PVC unions!

Shot of the finished door. The door seals both enclosures at once, it's the only thing that touches both rooms together besides the floor. This was possibly the most tricky part to get right, the locations of the door stops and weatherstrip have to be dead on for it to seal well, and the latch pin has to hold the right amount of tension on the door to keep it sealed. It only locks from the inside.

Detail of switches. First switch is a 7 day timer for the pump and filter, middle switch is a wifi switch for the light that can be programmed (for instance) to shut off in 5 minutes (to give me time to get in the tank) and to turn back on after an hour (to tell me when I should get out). The switch on the right is a standard dimmer, so the light isn't blinding after an hour of total darkness. You can also see the amplifier here.

Filled up for the first time! and 800lb of Epsom salts dissolved.

Finished product. Got a curtain for privacy while getting in and out, made a little step to make it easier to get into, and installed an outdoor shower right outside the door you see here. So you can clean up, get in, leave body, get out, rinse off, etc. It works very well so far! You can hear absolutely no sound inside, although I will admit to hearing one very low exhaust tone when I was in there the other day. All it's really missing is a good waterproof mat under the whole door area. I have a little piece of heavy tar paper there now, but I have a bed liner mat I think I'll cut to size. Thanks for checking out this project, it took me about 5 months of spare time to complete and cost about $2500 total.