Mike Arr

Thanks. I sized my shelves to accommodate plastic "bread trays" which are 26x22x5" and can be found used for about $5 each. They stack and are ventilated so I hope this allows me to keep the spuds to about one layer per tray for air flow and easy inspection. I think your storing technique depends on your cellar's initial condition. The Bubels' excellent Root Cellaring book recommends temps 36-40F and humidity around 90% for white potatoes. If you are drier than that then sacks, straw or shavings may be a good idea to keep the moisture around the crop at the "ideal" level. I'd go with that over peat moss which sounds like a mess! We'll see. I'm only speaking from theory at this point. I hope to have more substance to share when I have real experience next winter/spring.

It has been a while since I posted on this. The project shows a lot of promise.

1. Radon levels of 4.0 pCi/L is where remediation is recommended. Within a day of installing the ~$140 radon fan, my level dropped from 12 pCi/L to somewhere between 0.1-0.4 pCi/L, depending on the day. I thought I would need to fix many more things to get the radon to acceptable levels - like plugging 3-4 gaping holes in the slab that are currently serving as drains, but the fan got me there immediately.

2. I was able to take some temp and humidity measurements before winter ended, when some nights were still below freezing and some days got up into the 60s. The cold air inlet / warm air outlet venting were only half complete, but temperatures were stable and hung in the low 40s +/- 2-3 degrees, and humidity remained above 70%. This is for the entire 22'x22' area - I expect that I'll have more control when air flow is confined to a very well insulated 22'x4' area.  

Below are 2 pics - a close up of the venting and a wider shot with shelving. I am using the cheapest 4" drain pipe and harbor freight dust collection regulators to manage air flow. I'll have to wait until next fall to know for sure, but I think it's going to work great. Next comes the walls and insulation. Then lighting and some kind of insulated door. After that I'll get a couple hundred pounds of root veggies and see how they last into 2020. I'll be able to monitor temp/humidity outdoors and inside the cellar and will post a few graphs to show how well the thermal mass of the cellar dampens the temp and humidity swings outside.  

Shelves:

I understand it's best to not have shelves against the wall b/c a root cellar needs air flow. I can fasten mine to the concrete studs which provide a 7" gap to the wall. I'll probably frame out the shelves with 2x3s (cheap) and use 1x3s for the shelf surface (with gaps between them). I have lots of used 1x3s from another project. I'll build the shelves first to support the venting and then build the interior root cellar wall afterward.

The Bubel book suggests heavier wood b/c the moisture will make it rot in a half decade or so, but I'll go with this to see what happens. I don't expect them to hold a lot of weight and they'll be fastened to the wall. I have plenty of room for anything canned/jarred on the dry side of the wall.


Monitoring:

I think I'll get one of those Acurite 4-zone temp/humidity monitors. I wanted to get a new one to monitor inside/outside temp anyway, and I could place the 2 other sensors in the root cellar and see the temps from upstairs in the kitchen. I believe they can be set up to signal alarms if the temps pass certain thresholds - say below 32 or above 40 - as well.

That's it for now. I'll have more to share when I get the shelves started and 2 more holes in the wall.

Venting:

I had a super, over-engineered venting plan that I sadly, most likely will be abandoning. I'd run the 4" air inlet (blue) on the west side straight down to the floor to a regulated elbow. Above that, a tee would reduce from 4" to 2" and transverse the 22' east with 6 more 2" tees to dump out cold air along the way. The exhaust (red) would be a 4" drainage pipe that ran across the top and pulled out the warm air through its holes. I could then, theoretically, regulate all the inlets/outlets and create different temps/humidity microclimates for different things.

Then I finished Mike & Nancy Bubel's root cellar book (last night). I learned the exhaust vents are probably better being flush with the exterior wall so warm/condensation pockets don't form around the pipe. I'd have to run my exhaust vent under an I-beam meaning warmer air would collect up there. I now think it would be best to run the cold pipe straight to the floor and then all the way across to the other side. I may or may not use some sections of the drain pipe for this to let some cold air seep out along the way.

Radon Fan:

The interior root cellar wall needs to be at least 22' long to partition the room and I probably would have built about 4' deep (22x4'), but the radon fan must connect to a sump about 6' from the N wall. I have therefore decided to enclose the radon system within the root cellar. Since the fan might throw off a bit of heat, I'll fasten it as close to the ceiling as possible.

Side note: I do want to get my radon levels down - if I didn't care about that, the sump would be a great moisture source. I understant that it's harder to get the humidity high enough in root cellars without dirt floors. Further, the convection currents from the root cellar vents could potentially draw radon from the sump without the use fo the fan - off grid style. Or the radon fan could be used to pull humidity into the root cellar from under the slab. Heck, the radon may even irradiate the fruit and make it last longer for all I know. But enough with hypotheticals - Goal #1 is to get radon levesl down - so fan it is.

I am building a basement-style root cellar for several reasons:

1. I need to install a radon mitigation system which means one hole through the concrete foundation - so why not 3?

2. The 22x22' area is under the garage and not being used well. The former owner had a wood shop here, but it's cold and very damp. Condensation sometimes forms on the concrete ceiling and drips onto things. I removed drywall and found condensation on the north wall and the NE/NW corners. I hope that by partitioning I get two useful rooms - a colder damp one, and a warmer dry one.

3. I have piles of used fiberglass insulation and boards from another project that would otherwise need stored or thrown out.

4. To have a root cellar.

Priority is about in that order. Thanks to Sean at Edible Acres for the idea. The wall will be R13 insulated 2x4 with 2" foam board on the root cellar side. Not quite sure how I'll do the door yet. My constraints are that I have a limited area to run the 3 vents through the wall - they all need to go through a ~2x2' section so they are hidden by a deck/stairway leading to the garage. The root cellar in/out vents need to be as far from the radon exhaust as possible to not suck radon back inside (typical building codes require radon exhaust be 10' horizontal distance from a window so I'm aiming to exceed that).

I'll follow this with a couple posts with pictures on my plans - and then more updates in a few weeks when I start getting shelves and walls up.

I have been intensively youtube researching root cellars for a couple weeks and can verify that Dave posted the two best series on the internet. Most youtube videos don't actually have root vegetables in the root cellars - maybe a couple of squash, but mostly shelves of home canning or Campbell soup.

The Little Mountain Ranch channel has several other root cellar videos - one posted as recently as today - detailing the development of mold, what she did about it, the status of vegetables 5 months later. It's all very informative and well done.

Sean at Edible Acres has at least 2 other videos up - a 3 year follow up posted in the last month. I think Sean's videos are the best and suggest everyone watch him and buy plants from Edible Acres (I do).

I'm building my own root cellar like Sean's  - in a basement under my garage. The area, while not finished living space, was dry walled and musty - I pulled down the dry wall and found condensation on the north wall. I hope to use that to my advantage and create a long insulated wall to block the moist, root cellar side of the room from the dry side. The root cellar will be ~22ft long and maybe ~4ft deep. I'm still trying to figure out the depth and the best way to configure PVC ventilation for such a long narrow space.

I think you can move their pen - if they don't want to go back in right away throw in a handful of millet and they'll pile in. If necessary, you can lock them in for a couple of weeks to recondition them.

Our guineas used to come up onto our deck 2-3 times per day, but I put up a "gate" and now they rarely go up there anymore. It's just a section of plastic lattice from the big box store and I put it up for our toddler, not the birds, but it tends to stop the guineas. While they can fly, they generally would get onto the deck by walking right up the steps, so the gate stops them. Now they have to fly up to the rail, and when the do that they tend to stay on the rail. Their poop goes off the edge or stays at the deck perimeter and is washed away when it rains. My wife often shoos them from the rail, but I let them go unless they get onto the deck. We make sure to not feed them near the deck and I think that helps. Not sure if a gate will work for your layout but it has worked well for us.