Building A Walk In Cold Room

I am converting what used to be an old coal cellar in my basement into a walk in cold room. The room is approximately 6 foot by 4 foot with a 6 foot ceiling. There is a window in the room that was at one time used to chute the coal into the house. I plan on putting a small air conditioner in the window to maintain the room temp at about 50F. In the winter, cold air from outside will be pulled in via a small fan to save some electric. This will be used for both fermenting and serving beer, with serving lines running upstairs to a three tap tower in the kitchen located directly above.

Pre-construction Here is a shot of the room before major construction began. At this point the room has been gutted and cleaned up. It was a dusty, musty mess with almost 100 years of coal dust packed into the floor. I thought I might get black lung there was so much dust, but, I choked it down with some IPA and continued on.
Busting Up The Old Floor I was afraid of what microbiological critters might be living in the years of dirt and dust that had accumulated on the floor of the coal room, and being in poor shape, I decided that it had to come out. A few hours of sledge hammering and the old floor was history. A little homebrew conviced a friend to help carry the busted up chunks of the concrete from the basement.
Framing The Floor and Drain With the old floor removed, I decided to lay some wooden framework around the edges to help with the pouring of the concrete, and to give me something to easily secure the walls to. The photo below shows the frame in place, with me installing a drain in the center of the floor. I felt the drain was a good idea to make general cleaning of the room easier, and to allow for a large amount of liquid to drain in the event of a spill or carboy breakage. I had originally planned on running a PVC drain line straight down about 3 feet and filling it with aggregate. This plan changed when I took out the old floor and found that there was a cavity under the floor of the adjoining room, approximately 18 inches high by 4 foot wide and about 6 foot deep. This allowed for a place to drain without doing some major excavating. A rubber stopper is placed in the drain to keep it sealed unless needed.
Pouring The New Floor After I had the frame laid out around the room, I decided it would be best, with my amature concrete skills, to pour the floor in four seperate sections. This would allow me to easily put a slight slant towards the drain. I put an extra layer of 3/4 inch wood on top of the drain and then leveled it to the frame. With the drain staked into place, I removed the extra 3/4 inch peices of wood. This gave me a 3/4 inch drop from each side to the center of the room. I then cut 2 by 4's and ran them from the corners to the edge of the box containing the drain. The two sections in the picture were then poured (one at a time). You can barely see the 2 by 4 frame running from the corners to the drain on the front section (they're covered with mud). After these two slabs were set, I removed the frame and poured the other two slabs, using the edges of the set slabs as guides. It turned out pretty nice.
Framing The Room & Wiring Once the floor was set, I began framing the walls and ceiling. This was pretty standard construction and went quickly. I wired an overhead recessed light and put a switch on the outside of the box (visible in picture). Inside the box, I put a GFI protected outlet to run the AC unit.
Framing Around The Window I built a frame around the window opening using pressure treated decking lumber. I figured this was going to be a high moisture area and it could use the extra protection. It was at this point that I realized that I should have used pressure treated lumber in the floor and drain framework as well. The frame of the window slants towards the outside to allow any condesation from the AC unit to drain away from the cold room.
Hanging The Vapor Barrier I used some thick black plastic sheeting and hung a vapor barrier between the wood framing of the wall and the old stone wall of the house. This was recommended by several people. The walls to the back and right side of the room have earth behind them. Behind the wall to the left is more basement, and this wall is about 10 to 12 inches thick; as I imagine are the other walls as well.
Insulating I decided to use R-30 insulation in the ceiling, and R-13 in the walls. I could have put R-19 in all the walls but the front, as there was plenty of space between the wall frame and the stone walls, but figured that the thickness of the stone was probably fairly good insulation. The other factor was that I couldn't crame R-19 into the thickness of the 2 by 4 wall that leads into the box, so I bought a roll and R-13 and went with it. I figure that even on the hottest summer day, I will only need to drop the room 15-18 degrees to maintain 50F.
Hanging The Dry Wall Hanging the dry wall was a breeze in a room this small. I used waterproof sheet rock so it would be resistant to the high moisture in the room. Taping and spackling was just a easy, although I didn't enjoy sanding the spackle in this confined space of the cold room.
Painting the Floor and Walls This page still under construction. Stop back soon...