A root cellar sizing guide helps homesteaders plan adequate food storage space before construction. Most first-time root cellars are undersized — calculating your actual needs by food type and months of storage prevents costly rebuilds later.
Root Cellar Size Calculator
Storage Categories (check what you plan to store)
Storage Breakdown by Category
How to Size a Root Cellar for Your Homestead
Planning a root cellar requires thinking through three dimensions: how many people you're feeding, how many months of storage you need, and what types of food you'll actually store. Getting the size right before you pour concrete is critical.
Step 1: Calculate Storage Per Food Category
Different foods have dramatically different storage densities. Potatoes store compactly at about 60 lbs per cubic foot in bins. Winter squash takes more space — 4-5 butternut squash fill about 2 cubic feet. Canned goods on shelves run about 8 quart jars per cubic foot. Use actual quantities you plan to grow, not averages.
Step 2: Add 20% for Access and Air Circulation
Calculated raw storage space needs to be increased by at least 20% to account for access pathways between shelving units and proper air circulation. Without circulation space, produce rots faster from trapped ethylene gas and moisture.
Step 3: Separate Incompatible Foods
Apples and pears emit ethylene which causes potatoes to sprout early. Store them in separate sections or compartments. Onions and garlic need drier conditions than root vegetables. Consider a divided cellar with different humidity zones.
Step 4: Plan Shelving and Access
Deep shelves (18-24 inches) waste space — produce at the back gets forgotten and rots. Maximum shelf depth of 16 inches allows you to see and reach everything without moving other items. Plan shelving on all walls and a center island for root vegetables in bins.
FAQ
Is this root cellar sizing guide free?
Yes, completely free with no signup or account required. All calculations run locally in your browser.
How much storage space does a root cellar need per person?
A good rule of thumb is 10-15 cubic feet of usable shelf space per person per month of storage. For a family of 4 storing 6 months of root vegetables and canned goods, plan for 240-360 cubic feet of usable space — roughly a 10x12x3 foot storage area.
What temperature should a root cellar maintain?
Ideal root cellar temperature is 32-40°F (0-4°C) with 90-95% humidity for most root vegetables. Apples and pears do best at 30-40°F. Squash and pumpkins prefer slightly warmer conditions at 50-55°F. A good root cellar naturally stays at 35-40°F through winter in most northern climates.
How many bushels of potatoes does a family need for a year?
A family of 4 eating potatoes 3-4 times per week needs roughly 200-300 pounds (3-4 bushels) per year. A bushel of potatoes weighs about 60 pounds and takes about 1.5 cubic feet of storage space when in bins or crates.
Can you store apples near potatoes?
No — never store apples near potatoes. Apples emit ethylene gas which causes potatoes to sprout prematurely. Store them in separate rooms or at least on opposite sides of the cellar with good air circulation between them. Also keep apples away from cabbage, carrots, and other ethylene-sensitive produce.
Do canned goods need special conditions in a root cellar?
Home-canned jars do best in cool (40-60°F), dark, dry conditions — a root cellar works well. Keep jars off concrete floors to prevent moisture absorption and rust. Commercial canned goods tolerate wider temperature ranges but last longest below 60°F. Avoid temperature fluctuations which reduce shelf life.