My Latest Project - Walk-in Cooler

[John Beere]

What are the interior walls going to be covered in? I'm a little concerned about condensation, although I can never get straight in my head where you should have the vapor barrier. How are you handling the moisture issue?

Well the interior walls are inside the garage. I'm a little perplexed by the vapor barrier as well but am going to trust the Reflectix. This room is 10' tall and I am only using 8'. There will be insulation on the top but the walls / insulation will be somewhat exposed above the unit. I think I will install an exhaust fan up there to draw air (and hopefully any moisture) out of there.

 

[the_bird]

Is the Relfectix the metal-looking stuff I see behind the framing?

 

[John Beere]

Is the Relfectix the metal-looking stuff I see behind the framing?

Yeah, I list the details of it in post #19...

 

[John Beere]

Slight update - as suggested, I extended the thickness of the walls two inches by adding a 2"x2"x8' to each joist. I also got some proper strapping which made the job go a lot quicker. I didn't take the insulation all the way out but I did re-fluff it as much as possible. There are still some small spots I need to fill, but overall - the walls are done. Here are two photos:

Edit: - I forgot to mention I left the bottom across the back un-insulated for now as I have to run some wiring through the wall first.

 

[Musthavbeer]

What about the floor? Cold decends. I've erected a few cold storage buildings and done several walk-in coolers and freezers. When built there is always blue DOW under the slab. Blue DOW is great in that it will not absorb moisture (closed cell) and it will support plenty of weight. You could lay about 3" on the floor and then protect it with 1/2" ply. Make sure you don't have anything metal going from inside to outside or the outside will sweat like crazy, (metal door frame).

 

[John Beere]

What about the floor? Cold decends. I've erected a few cold storage buildings and done several walk-in coolers and freezers. When built there is always blue DOW under the slab. Blue DOW is great in that it will not absorb moisture (closed cell) and it will support plenty of weight. You could lay about 3" on the floor and then protect it with 1/2" ply. Make sure you don't have anything metal going from inside to outside or the outside will sweat like crazy, (metal door frame).

Thanks for the info. I planned on building a false floor about 5" off the slab and insulate it with two layers of 2" foam board as well as a layer of Reflectix. No metal at all.

Hmm, I just looked at the Dow board on Lowes Website... it has a higher R value than the Insulfoam I was looking at. The Dow board has an R value of R3 per 1/2". The insulfoam board has an R value of R7.8 per 2". Now its really coming down to how much insulation does this thing really need?

 

[Musthavbeer]

For cold storage the usual is about R30-34, freezer is in the R-38-48 range. I wouldn’t build the sub floor. I would spend that money on the Rs under the ply and then use EDPM (rubber roofing) for the floor surface and turn it up the walls 3” or so. Lowes and I think HD now sells EDPM cut to length. You can glue it down or just pin to the walls with trim at the base.

 

[John Beere]

For cold storage the usual is about R30-34, freezer is in the R-38-48 range. I wouldn’t build the sub floor. I would spend that money on the Rs under the ply and then use EDPM (rubber roofing) for the floor surface and turn it up the walls 3” or so. Lowes and I think HD now sells EDPM cut to length. You can glue it down or just pin to the walls with trim at the base.

Thanks for this information. I wasn't sure how sturdy the foam board would be to use as the floor but it sounds like it will work well. I'm going to Lowes this evening to see if they have the Dow board in stock... I know they have an entire pallet of the Insulfoam.

I think I will use the higher R-value Dow board for the floor for sure if I can find it.

So my options for the walls are either two layers of the 2" thick R7.8 Insulfoam ($25 each) for an R value of R15.6 - OR - five layers of 1/2" thick R3 Dow board ($10 each) for an R value of R15 (but 1.5" thinner). Any opinions?

 

[Brewpastor]

I am always concerned about floors related to spills, fermentation overflows and so forthDo you have any thought in this area? Slopped towards the door or a floor drain might be a suggestion.

Also, and I may have missed this, what wall covering are you looking at. I like the slick, white bathroom board. 4x8 sheets and nonporous.

 

[Brewpastor]

Would a dehumidifier be worth considering? I live in the desert, so moisture isn't a concern, but with all the moisture build up concern being voiced, I just thought maybe that would be worth looking at.

 

[John Beere]

Lowes and Home Depot both sell thin 4x8 thin sheets of wall coverings that I think are made of plastic - looks like the same stuff used inside of chest freezers. I am considering using this with a textured finished for the walls. I initially thought I'd use that for the floor as well and then just put a heavy rubber mat, cut to size, on the floor. Don't know what its called specifically but it is a mat with a ton of holes drilled through it. I think Musthavbeer's idea of using EDPM (rubber roofing) for the floor surface might be a good one if I can find it. I'm going to investigate that this evening as well.

It is my understanding that a de-humidifier is really nothing more than the guts of an air conditioner. I talked with Mr. Malty (http://www.mrmalty.com/brewstuff.php) - he stated "The only downside is that you need to be a little careful at first that it doesn't ice up. Once you pull out the moisture, it is fine." This was my understanding as well - that the AC is going to be pulling moisture out when it runs.

 

[Brewpastor]

That all makes sense to me.

 

[Whake4]

you will probobly need a low ambient kit such as a head pressure control and a Suction Line acumulator to protect the compressor from getting liquid refrigerent back when its down at such a low temp. or you will prob freeze up the evap

 

[highwayman]

I am wondering if a set up like that would work during winter months when it gets cold. It looks really good at this point.:rockin:

 

[Exo]

But he lives in GA...south GA...

 

[Whake4]

It would prob work fine year round you just need to add a few components to make it work right or you will be buying a new window unit every couple of weeks. Those systems are not set up to run in such a low ambeint temp

 

[John Beere]

The AC may go down within weeks but I am willing to gamble it based on the success of others. Specifically Jamil Zainasheff who inspired this project (http://www.mrmalty.com/brewstuff.php). I have been in contact with him several times preparing for the project and he confirmed his unit is still going strong - for over 4 years now. He also confirmed that his unit runs in 30 minute spurts - maybe only twice a day to maintain the sub-40 temperature. I can only hope I am able to create something anywhere near that efficient.

My favorite quote:

"An A/C guy that lives down the street told me that it wouldn't last more than a week, running at 37F. He was certain of it and told me I was an idiot for wasting my money on it. Regan Dillon at www.morebeer.com told me it would be fine, which is why I tried it in the first place.

Well, about 4 years later, it still works perfectly. Thanks Regan! Bite me A/C guy!"

But just in case my unit does go down in flames - where could I find these components for my replacement unit? and can a regular Joe install them?

 

[John Beere]

Just to follow this up... it is my understanding that the AC is really only at risk of freezing up when there is a lot of moisture in the air. This will be an enclosed space that shouldn't have much moisture at all once its up and running. Mr. Malty brought up the same point which I posted earlier in post #41:

"I talked with Mr. Malty (http://www.mrmalty.com/brewstuff.php) - he stated "The only downside is that you need to be a little careful at first that it doesn't ice up. Once you pull out the moisture, it is fine." This was my understanding as well - that the AC is going to be pulling moisture out when it runs."

 

[Whale4]

I dont think that it wont work, just trying to save you some possible headachs down the road. And no the average home owner wouldnt be able to install or purchess these parts

 

[John Beere]

I dont think that it wont work, just trying to save you some possible headachs down the road. And no the average home owner wouldnt be able to install or purchess these parts

Please don't take my posts as contrary... I value all of your input. Like I said, I'm going to chance it as-is but am willing to gamble that - and the fact that I might be back here asking for more info on its replacement when it goes down in flames! Consider it an experiment (at my expense) for all the people on the board who have taken interest in my project.

Thanks much

 

[D*Bo]

How does the R rating work?
higher the number, better the insulating properties?

 

[Whale4]

No problem no offense takin. If it wernt for risk takers there wouldent be half of the great ideas out there in this hobby Im pulling for ya because Im thinking of going to the next step with this idea

 

[Whale4]

yes higher R= better insulating properties

 

[Bernie Brewer]

Lowes and Home Depot both sell thin 4x8 thin sheets of wall coverings that I think are made of plastic - looks like the same stuff used inside of chest freezers. I am considering using this with a textured finished for the walls. I initially thought I'd use that for the floor as well and then just put a heavy rubber mat, cut to size, on the floor. Don't know what its called specifically but it is a mat with a ton of holes drilled through it. I think Musthavbeer's idea of using EDPM (rubber roofing) for the floor surface might be a good one if I can find it. I'm going to investigate that this evening as well.

It is my understanding that a de-humidifier is really nothing more than the guts of an air conditioner. I talked with Mr. Malty (http://www.mrmalty.com/brewstuff.php) - he stated "The only downside is that you need to be a little careful at first that it doesn't ice up. Once you pull out the moisture, it is fine." This was my understanding as well - that the AC is going to be pulling moisture out when it runs.

I'm pretty sure what you're describing is called milkhouse board. Good stuff, but it's not cheap- something like $25-$35 for a 4x8 sheet.
Also, you mentioned that you were going to furr out the exterior walls to make more room for your insulation. That's a good idea, but since your cooler is going to have a change in ambient temperature on all sides, you might want to consider all of the walls as "exterior" and furr out all of them for added r-value. Just my .02 Cheers.

 

[John Beere]

Update on the AC: I test wired a new Ranco controller into the AC this evening. This was the step I was most worried about and, now that its done, I can't believe how easy it was... I was able to completely bypass the built-in controls on the first try. I will officially re-wire it tomorrow. The diagram at http://franklinbrew.org/members/sj/walkin.html is correct, even for my brand new AC.

Lowes didn't have but about 10 sheets of that Dow board so I bought a pallet of another called R-Max. Its 3/4" thick with an R value of R5. I plan on lining the walls 3 sheets thick.

 

[John Beere]

I'm pretty sure what you're describing is called milkhouse board. Good stuff, but it's not cheap- something like $25-$35 for a 4x8 sheet.
Also, you mentioned that you were going to furr out the exterior walls to make more room for your insulation. That's a good idea, but since your cooler is going to have a change in ambient temperature on all sides, you might want to consider all of the walls as "exterior" and furr out all of them for added r-value. Just my .02 Cheers.

Thanks. The cheapest I could find was around $11 per sheet. I'm still debating if I want to put that much into it...

Yeah, I've already furr'ed out the interior wall as well as the two exterior and plan on doing it to the fourth wall as soon as its built. Thanks for catching that though.

 

[uglygoat]

how much do you have tied up in materials cost, and do you have an estimated energy cost for a year of 37 degrees?

i want to turn my little celler into a cooler so i can start kegging and run the lines out to the bar, but i'm flinching at the energy costs, especially when i have to keep the girls warm in the winter upstairs.

 

[John Beere]

how much do you have tied up in materials cost, and do you have an estimated energy cost for a year of 37 degrees?

i want to turn my little celler into a cooler so i can start kegging and run the lines out to the bar, but i'm flinching at the energy costs, especially when i have to keep the girls warm in the winter upstairs.

I will list a full list of materials and costs when I'm closer to finished. At this point, I know I've bought extra materials that I am going to use for a fermenting cabinet, etc.

As far as estimated energy costs - I really don't know how to calculate them as I don't know the final R value. Mr Malty has some estimates for his cooler at http://www.mrmalty.com/brewstuff.php

"Question: About how often is it running in the summer to keep those temps?
Answer: It depends on how hot the day, but even on 110F days, it runs maybe 30 minutes total once or twice a day. I've figured out it costs me around $2 or $3 per month average across the year."

 

[John Beere]

Made some progress today... I totally re-wired the AC to completely remove the built-in controls as well as got it working off of only one plug. The diagram I linked to last night shows the need for a second plug and is what I tried last night. The only reason the ground is clipped is I cut it last night during my test.

I filled the vent in the AC with great stuff as shown here:

And I then covered the outside of the styrofoam with some extra Reflectix. It probably won't help anything but it gave me the warm-fuzzys.

After that, I framed out and installed the AC in the window, plugged up all the holes with great stuff, and lined it with Reflectix like the rest of the walls. I then wired up a new breaker in my breaker box, ran it under the house (absolutely horrible place), out the back of the house through 1" conduit, into the garage, and wired up four new plugs in the garage (only one in the cooler itself - been needing better power out there for some time). And finally, I put a couple of pieces of the foam board on the walls just to see how it was going to work. Turns out there is just no way I can compress the insulation behind the foam board all the way down to the 2x2 etensions I added. So I pushed the board as square as I could and nailed into place leaving about another 1.5" gap. The insulation is pretty much taking up all that room but the back of the foam board is lined in foil and it says dead spaces is OK.

Thats it for tonight... pooped

 

[Capa]

Wow. I'm extremely impressed/jealous...ha. The fantastic ideas on this site never ceases to amaze me.