How to Make a Root Cellar With a Rounded Roof

Build a Root Cellar Outside

• 1

  Look for a natural slope or hillside to build the root cellar. A hollow hill makes a very functional root cellar. If you do not have a natural hillside, you have to dig straight down into level ground.

• 2

  Choose the shell for your root cellar. You may use treated plywood to build your own ceiling and walls, but a metal trashcan or an old refrigerator makes a very adequate casing for the cellar as well.

• 3

  Cut two plywood sheets to half the length and width of the proposed ceiling of the root cellar, and two plywood sheets to the size of two of the walls with a handsaw or table saw.

• 4

  Cut two to four 2-by-4s, depending on the size of the cellar, to the proposed height of the cellar.

• 5

  Dig out the hill or excavate the area of ground where the root cellar will be placed with a shovel, bracing the hole with the plywood sheets and 2-by-4s to prevent dangerous collapses and cave-ins. Remove enough dirt to make a hole 2 inches wider and longer than the root cellar you plan to build.

• 6

  Dig the back end of the root cellar so it sits higher than the front end, creating a slope to allow rain and moisture to drain away rather than seep in or flood the cellar.

• 7

  Cover the floor of the cellar in 4 inches of sand or rock to provide further drainage.

• 8

  Line the hole with tarp, covering the floor and all four walls of the cellar.

• 9

  Place the trashcan, refrigerator or root cellar shell inside the hole. If you are constructing a root cellar out of new materials, stack cinder blocks along the dirt walls.

• 10

  Place 2 to 4 inches of dirt and sand or rock on the floor to create a dirt floor for the cellar.

• 11

  Cut 2-by-4s to the length of each wall of the root cellar.

• 12

  Hammer the 2-by-4s together using 1/2-inch nails to create a ceiling frame.

• 13

  Tack chicken wire to one long side of the ceiling frame. Bend the wire into an arching shape before tacking it to the opposite side of the frame. Repeat on the two other sides of the ceiling frame to create a rounded roof support.

• 14

  Cover the chicken wire with tarp and hammer or tack it into place around the wooden frame.

• 15

  Hammer two to three hinges to the back end of the ceiling frame. The other side of the hinges should be hammered to the back wall of the root cellar.

• 16

  Close the lid on the root cellar and cover it with grass clippings, mulch or leaves to provide natural insulation. You may need to recover the roof every time you open and access the root cellar.

Build a Root Cellar Inside

• 17

  Look for a damp corner of your basement to build a new root cellar, choosing a spot with at least one exterior wall.

• 18

  Choose two places on the wall to run 3-inch pipes to the outside. You may need to consult with a plumber to successfully install these pipes, which should be constructed of PVC.

• 19

  Cut pipes to run from inside the root cellar straight to the world outside, placing a closed blast, or gate, valve onto each interior end. One pipe should meet the exterior wall at the highest point, the other 1 foot above the ground outside. Close one of these valves whenever freezing temperatures are expected.

• 20

  Seal the pipes around the wall with insulating foam to prevent unwanted air leakage.

• 21

  Mark out the area on the floor where you will place the walls with a market, and cut 2-by-4s to size with a handsaw or table saw.

• 22

  Cover the marks on the floor with construction glue and place 2-by-4s onto the glue, pressing firmly to ensure good contact.

• 23

  Nail upright 2-by-4s to the wooden floor frame, spacing them approximately 16 inches apart. Each of these 2-by-4s must be to the same length, the approximate height of your root cellar and at least 1 foot shorter than the ceiling of the basement itself.

• 24

  Nail moisture-resistant wall board, also known as green board, across the upright 2-by-4s to create the outer walls of the root cellar.

• 25

  Stuff fiberglass insulation between the studs, pressing it in tightly to press against the green board.

• 26

  Nail green board to the 2-by-4 studs to create the interior walls of the root cellar and hide the insulation. Leave an opening, a gap between studs, to serve as a door to the root cellar.

• 27

  Nail horizontal 2-by-4s across the top of the studs and wall boards to build a ceiling frame. The ceiling frame should cover the door gap.

• 28

  Measure the width of the room from the door wall to the back wall.

• 29

  Divide the width measurement by three. Cut 2-by-4s to two sizes: one to one-third of the measurement, and two to one-third of the measurement with 3 inches added. Cut a 45-degree angle to one end of each of these longer 2-by-4s.

• 30

  Nail the angled end of one 2-by-4 to the flat end of the shorter piece of 2-by-4. Repeat the process on the other end of the short 2-by-4 to create a single long piece that has a slight U-shape to it.

• 31

  Repeat steps 13 and 14 to create several ceiling supports for the root cellar, one for each 1 1/2 feet of the length of the back wall.

• 32

  Nail the ceiling supports into place on the ceiling frame, from back wall to front wall.

• 33

  Cover the ceiling struts with more green board, cut to size to follow the curving slopes of the 2-by-4s, to make a rounded roof.