I am working with a client on a home addition, and one element of the design is a wine cellar. Here are some basic facts about the existing home:
From my early research into the topic, the opinion amongst the wine crowd seems to be that A/C is a basic requirement for any wine cellar. I would like to challenge this assumption and see if we can build a passively cooled room.
The homeowner wants the ability to store up to 500 bottles. Due to the nature of the kitchen addition, and over-due HVAC upgrades, there are a lot of possible approaches available to us. One idea I would like to consider is the use of Earth Tubes to draw in ground-temperature air into a basement space.
Does anybody have experience building out passively cooled wine or root cellars?
While you wait, I'll keep the thread open. One of my concerns would be circulating air into the ground to be cooled could also create an accumulation of moisture with all of the musty related problems. And it would not be passive, you would need a fan to move that air.
How passive do they want to get?
I suppose I meant passive in the sense that I don't need to add a dedicated A/C system or supply line to the room - so a fan would fit the bill. The moisture build up is a concern of mine, too.
It is called a cave, that is about the only "passive" environment that will keep it around 55 degrees with 70% humidity - the closer you get to the surface or into a house the more conditioning you need
Root cellars vary based on climates & location - best to contact your local coop for advice from those that do it in your area
Nick, the only experience I have is with : http://en.wikipedia.org/wiki/Ground-coupled_heat_exchanger .
A simple home with a perfect basement wall and floor, however, should never be permeated. It's just more sensible to enclose a room down there and use goold old HVAC to maintain desired temp & humid. Great luck with your project!
Thanks for the link. Part of the reason I was asking was exactly because of my concerns of punching holes in a perfectly good foundation wall.
For a root cellar, a very clever designer covered the entire basement slab with dimple mat (Delta FL), then R-10 of XPS, then subfloor, etc.
The root cellar is a large closet in the basement that is air-sealed and insulated from the rest of the basement. The dimple mat flows under the closet walls, and is open to the root cellar. There is an efficient low-CFM fan to exhaust any potential ethylene (from vegetables) to the outdoors.
This design uses the entire basement slab area to exchange heat (or "coolth" to non-techie folks) and should be able to maintain 55 degrees in the root cellar/closet year-round. The R-10 above the dimple mat in the rest of the basement will insulate the slab from heat delivered to the finished basement. As an additional benefit, this also negatively pressurizes and exhausts the entire basement slab, thereby reducing the risk of radon as well as moisture intrusion.
Good luck on your project!
Thanks for the reply! This sounds like a promising approach. The slab is about 600sf, uninsulated and >4' below grade, so I think it could work as a heat exchanger. According to this site, a 25sf area would accomodate the size of the cellar needed. I will throw these numbers at the engineer in my office for a gut check.
Joe Lstiburek has a nice article on wine cellars. It is also available on the buildingscience.com website. You might have already come across this in your research: http://www.buildingscience.com/documents/insights/bsi-010-wine-cell...
I think it appropriate to regard A/C as something you would only need if you had bad design, bad implementation or insurmountable location contraints (e.g. a penthouse on Michigan Avenue (poor fella!) or a home that needs to be built on piers on the coast of South Carolina). In Detroit, you should be able to create a cave. Instead of digging down 20-40 feet, use insulation to thermally separate the wine cellar from exterior/interior conditions. Thermally couple the wine cellar to the ground - the part that is 4 or more feet down. You can also make ground "deeper" by insulating it with a rigid insulation foundation skirt. If you are putting a new foundation under the addition, then you have great opportunities to do this right.
Remember to insulate and provide vapor control underneath floor framing that is above the wine cellar. In fact you should separate all wood framing from the wine cellar conditions.
The concept that Marie relayed is interesting and clever, but I think a wine cellar design should focus on radiant and conduction transfer of heat and not rely on or induce a lot of airflow. Plus, I really don't like the idea of using a wine cellar as a fat section of radon vent pipe.
That's a great link, thanks for sharing it! I agree with you about not venting subslab vapors through ambient air. It looks like Lstiburek's approach is similar in the sense that the concrete slab acts as a heat sink.
There's always glass! http://www.houzz.com/photos/wine-cellar/glass-enclosure
might not meet temp/humidity goals, however