I've decided to build a 144" x 80" outer dimension walk in cooler off the back wall of my garage. Eventually, I plan to have an insulated trunk line through the wall with a number of taps in the garage with keg storage in the walk in. Ghettogyle Greg is my brewing brother/neighbor and has been helping with this project thus far.
Should be a fun project. I have a budget of about 3K left and I've spent about 1K so far (but this includes a 12' x 6' lean-to shed which is framed out now but needs to be sheathed, roofed and painted). I expect the shed to free up a fair amount of space in the garage that I can use to more comfortably brew. I've got way too much schit in my garage.
I currently have way too many chest freezers so I thought a consolidation of these via a walk in would be a good idea. I will use this thread to document the process. I also need more bottle storage as I have a significant collection of commercial and homebrewed beer in 750 mL bottles that I could be doing a better job of cellaring with.
So far I have a 6" deep base course foundation that has been solidified with portland cement, squared and leveled concrete footer pads and a waterproofing treated 2x6 base built. The base is lagged to the garage wall and is not going anywhere. I plan on insulating the space in the floor and getting a 6 mil LDPE vapor barrier sheeting and hopefully 3/4" tongue and groove OSB flooring down by the end of the weekend. I decided to forego an insulated slab/foundation as that would eat up my budget significantly. It would definitely be more ideal but if I went this route, I would be broke before I could conceivably finish the walk in. I think a well insulated raised floor should suffice at a significantly lower price.
Here's the floor as it stands now.
And today I put in staggered 1/3rd spacing cross-members. This should allow me to support more weight in the cooler once it is finished.