Big thanks to this sub for the knowledge and advice and a personal word of advice to those sweating the small stuff contemplating a build: get the basics right, make a plan, and get it done. I know my build is far from perfect, but it's everything I could have hoped for so far. We are about 5 months in and are using it \~5x a week.

I am by no means an expert, but did a lot of reading on here and elsewhere before finally breaking ground. Definitely made some mistakes, but learned a lot, and really enjoyed it. Only wish I started it earlier! Details below for anyone interested! 

* Detached block garage - plan was to convert from unfinished space to a gym and include the sauna as the corner-piece. Drylocked walls, foamboard insulation, framing & drywall. Back wall of sauna is on exterior wall, left air gap before sauna framing, no drywall.
* Sauna is 8'x6'x9'
* Framed out with 2x4 lumber for the walls, 2x6 for ceiling joists. Rockfull insulation with foil barrier, furring strip air gap then tongue and groove
* Pine t&g from local lumber yard (more expensive than Home Depot, but difference in quality was absurd. Kept the best knot free boards for back wall and ceiling, tried to hide the knottier pieces lower and on the front and side walls. Ripped some cedar boards to make a duckboard walkway for the floor. 
* Benches framed out with 2x6s and topped with ripped clear pine boards. Used a router to round over the edges, sanded smooth. Roughly 40" and 56" off the ground. \~24" wide. Secured via cleats The lower bench was a little too high to get up to comfortably, so built a little step ladder out of some scrap 2x4s and the ripped pine. 
* Treated benches and walls with Supi Saunavaha Sauna Wax
* No drain. I know not ideal, but hasn't been a huge issue for us yet. Cleaning more annoying, sure, but so far I don't regret it, Would have been a huge headache to add one. I did treat the concrete with Ghostshield concrete sealer which worked pretty well.
* Easy access to new 100 amp subpanel to run the wiring. Electrician in the family thankfully, lucked out there. 
* Harvia 9kw Cilindro with Xenio WiFi Controls - Didn't realize how much more expensive it would be to add Wifi, but honestly can't imagine not having it now. Worth it.
* AC Infinity Cloudline fan under the bench, opposite heater. Intake vent above heater. Went with the wireless remote, which is nice, but the batteries die really quickly, kinda wish i just wired the remote from the fan.
* Door and heater sourced from The Sauna Place - they were great
* Work was all DIY'd, material costs probably \~$5-6K all-in

  




Humble DIY Garage Sauna Build