[AlanE]

I'm desiring a root cellar for a new construction home and, at this stage of the planning process, I'm interested in doing some brainstorming before any concrete is poured and before the house plans are finalized.

Here are my concerns and possible trade-offs:

1.) The house will incorporate seasonal heat storage under the basement slab.
2.) Hot water will use solar thermal system.
3.) Home heating from radiant heating system embedded in floor.
4.) GSHP in conjunction with vertical, closed-loop wells.
5.) I'm open to the idea of adding homemade solar thermal charging plates near the well-field so as to add additional heat capacity to the field as the field will be used to primarily extract heat and send it to the home, that is, the house won't be sending waste heat back into the field during the summer.

Now for the root cellar.

The vision at this point is to have the root cellar outside of the basement envelope, built of concrete and with a series of barrel vaults on the roof, with a door way, or even a small tunnel, leading into the basement, and then burying and surrounding the root cellar with earth.

Here's a graphic of the layout at this stage:


The plan is to run the radiant tubing underneath the freezer section to collect all of the cold migrating into the foundation and ground, and pipe the coldness to the adjacent sections - more tubing in the two cellars adjoining the freezer (because they are to be kept at a temperature just above freezing) and then the tubing continues into cellars #3 and #4 so as to lower the temperature in those rooms below the ambient below-ground temperature but not so low as cellars #1 and #2 and then finally the tubes run into the larger common room in front, cellar #5, to aid in keeping the temperature at a little below ambient.

The heat generated by the freezer unit would be piped out of the cellar and dumped into the home's hot water heating system.

My concern in how to marry the idea of seasonal heat storage in the below basement ground while mitigating the flow of cold/heat between the house and the cellar. My idea, at this point, is to have the cellar placed a few feet beyond the basement wall and construct a small passage way between the basement and the cellar. With the exterior of the cellar insulated and dry earth filling the space between the basement wall and the cellar wall I'm hoping it's possible to have two dissimilar temperature building envelopes being in such close proximity.

Of course the easy solution is to place the cellar far away from the home but if we do this then we lose the convenience of having this cellar within the home and we have to trudge outside to get anything from the cellar and this decreases the convenience.

Any feedback would be appreciated. I've searched the intertubes and I haven't really come across any reference to such a cellar design. There is discussion about running glycol underneath freezer units/buildings in order to prevent frost heaving but no one has written about taking that migrating cold temperature and distributing it over a larger area in order to make refrigerated compartments with cooling done passively.

I've read the radiant heating thread and the DIY heat pump thread and I was impressed by the referencing of engineering details in those threads and was hoping that perhaps some of you had come across work that deals with the cooling/freezing side of things. Condensation isn't a problem in this case because I'm aiming for high humidity in most every small room in that cellar. Cellars #1 and #2 will he having dirt floors in order to aid in the boosting of the humidity levels. The roof will be a barrel vault in order to prevent condensation from forming on angular objects and dripping down onto the food.

I'm hoping to make this a DIY project - the construction of the concrete structure will pose the least problems for me in terms of experience and knowledge. The environmental controls and radiant systems are new territory for me, so I'm reaching out to the collective knowledge base here for ideas and feedback.