🏕️ Welcome to The Survival Spirit! Your go-to resource for online survival guides and tips 🏕️ 

How to Build an Underground Cellar

All your essential goods, canned food, vegetables and fruits need some special place to be stored, safe from heat, rain, and all the other viscous elements that can spoil them.

The best option is to build an underground cellar.

Spacious, ventilated, and very safe underground storage will actually not cost you as much as you initially think and will serve you and your family as a long term asset for years to come.

Underground cellars have been utilised by humanity for many years. Their primary purpose, traditionally, was to be used as refrigerators. However, you can also use an underground cellar as a wine room, shelter, or storing room.

It can be a slightly complicated building process to create the cellar, but believe us, once you have the root cellar (another name for it), you will be wondering how you were able to ever live without it, previously!

The basic things you need to have in your underground cellar

When you store your foods for winter, you need to keep the cellar’s humidity as high as possible to prevent the food’s shrinkage and spoilage.

You want your sweet apples, pears, potatoes, and carrots to stay as good as new until spring when the fresh products will be available again.

You can achieve ideal humidity in your cellar by doing one of these things:

Leave the floor as it is 

Your underground cellar will naturally have a dirt floor that gives a natural humidity, perfect for all the stored foods.

Our ancestors used this method in their basement storages, and it was a good and cheap way to support an ideal climate in your cellar.

Create artificial humidity 

If you don’t like the idea of a dirt floor and would prefer to build it out, you can wet the floor from time to time by sprinkling with water.

In addition, place some pots with water all around the cellar and they will help keep the humidity at the optimum level.

Use equipment 

You can use electric humidifiers in your underground cellar from time to time to keep it stable and moist.

There are many portable versions of these on the market, so you can pick up one out that will be most suitable for your particular cellar’s needs.

However, maintain proper safety checks if you go for this option, otherwise they’ll be a fire coming your way!

Now, you have the ability to control the humidity in your cellar, but what about the fungus and mold?

Yes, we all know that it is very possible for food to get moldy in very moist air since spores are always floating and waiting for a chance to strike!

In order to prevent the mold from occurring, you have to take care of another basic, but essential element in your underground cellar…

Good ventilation

It is a crucial aspect that needs to be properly installed into your underground cellar to keep everything there as fresh as possible.

You can implement two types of ventilation in your underground cellar — natural or mechanical.

Of course, when people first invented cellars, they only used natural ventilation. This basically consists of two holes in your cellar.

They can be little windows or a window and door placed in front of each other. This helps the air travel through the storage areas freely.

This technique provides an easy way to create ventilation inside the cellar, but it also has its list of shortcomings:

  • you will need to control the ventilation process all the time, opening and closing doors and windows.
  • it cannot provide enough ventilation if there is no wind.
  • you cannot do it when it rains.
  • you have to make the walls of the cellar high above the ground to make proper air channels for the ventilation system.

If you have problems with the natural method of air ventilation or don’t want the risk that comes with it, you can use the mechanical one.

You can find various mechanical ventilation systems on the market, and they all have different functions and purposes.

You should choose the most suitable one for your particular cellar, but this kind of ventilation, although most popular, also has a few its own disadvantages.

For example:

  • it can be costly in comparison to the natural one.
  • you need to control the humidity better, since the artificial ventilation can make your cellar dryer

Overall, however, this is the best option, although a little more pricey.

Your first step in the building of an underground cellar: creating a hole

Your underground cellar adventure begins!

First of all, decide how big you want your cellar to be and if you need some professional help to dig it or if you can manage it by yourself.

It is very hard work to dig a hole for your root cellar, so consider renting a tractor or a backhoe for this part of the process.

So, now you have a plan, and you’ve decided on the place for your future underground cellar. Next, it is time to excavate the ground and dig out that all important hole!

Step 2: Good flooring for an excellent cellar

Now you have a proper hole in the ground, you should choose which flooring option you prefer.

If you decide to leave it as it is, and to have that dirt floor and humidity we discussed earlier, you will need still need to strengthen the base of the floor.

Just place a couple of inches of gravel on the floor to provide the support you need, and that’s all there is to it.

Important Note: Before starting the flooring process, you need to place all the strengthening constructions for your walls and prepare the placing for its supporting pillars.

If you want to have a custom-made floor in your underground cellar, you should consider making it from concrete.

With this option, you should still lay a base of gravel, about seven inches thick in order to provide the necessary stability.

Step 3: All about the walls

You have several options when it comes to the walls in your cellar. You can make them from concrete, just like the floor, use bricks or rocks, or even make them from wood!

It will totally depend on your taste, but we must warn you that if you pick wood, it’s possible that your cellar will be ruined as a result of natural causes.

Wood is obviously a naturally occurring construction material, so it can get crumbly and be destroyed by insects and extensive humidity in a cellar-type climate.

The most important aspect that should be considered when you are building your cellar’s walls is their durability.

Will they withstand constant variations in outside temperature?

Will they be strong enough to hold the roof?

Once you’ve decided which kind of walls you want, you can now place the pillars that will hold the roof and start laying your wall material.

Do not forget to make necessary holes for artificial or natural ventilation you are planning to install! 

After completing the walls, you can now move to the roof.

Step 4: The Door

There are a few factors to consider before installing the door. The cellar should keep an optimal temperature all year long, but some outside factors can influence it, such as extreme heat or extreme cold.

In these particular cases, we would recommend consulting with an root cellar expert to advise on your door positioning. This short terms expense, who save a huge amount of frustration and cost in the long run.

Generally speaking, though, you need to keep the door away from the sun as best as you can, to prevent the warming up of the air and food inside.

You can achieve this by placing a door on the northern side of the cellar if you live in the Northern Hemisphere. Our friends on the Southern side of the planet should face their cellar door to the South.

Step 5: The Roof

The roof part of the cellar is the most daunting part of the whole process.

It is one of the last parts of the building, and you can make it in different ways too, just like with the walls. But we prefer this method, below, since it is one of the most bulletproof ways to make the cellar roof.

To start off, you need to make a wood form for your roof, not flat, but with arches to give a little height to your cellar.

Then, you need to apply and press plywood and secure it with nails to create a strong construction for your cellar. You can now place the roof above the cellar, put in the rebar, and pour down concrete to finish the roof.

And it is done!

Step 6: Electricity and ventilation in the cellar

Congratulations, you’ve just made a little underground cellar!

If it is small enough, you can just use a flashlight or a candle to look around it. But if you want to have a big and wide cellar, you definitely need electricity there.

It is only required for light, so you can install the wiring at any point after finishing the cellar. However, if you want the cords to be hidden, now is the best time.

We strongly recommend hiring a professional for cellar lighting because, as you know, we’ve previously spoken about the very humid atmosphere.

You will need special wiring and isolation to prevent fires there, so a professional opinion is very important.

You can also use portable lights which are an easy and safe way to avoid any wiring in your underground cellar.

You might also wish to invite a professional to install your mechanical ventilation. If you need electricity for it, you can speak with an electrician and ventilation expert about your best options.

Now, all the hard work is finished, and we can move to the fun part.

Finishing touches and how to store your food

Your root cellar is now finished, and you only need to place stairs and internal doors (if you wish!) inside your food storage cellar.

You can also work on the walls, but we think the best thing you can do is to leave it how it is. Quite rustic and cellar-looking.

This is time to put some shelves and hooks in your cellar and place food on them.

Speaking of shelves, you need to keep in mind that standard wooden shelves can be deformed because of the humidity in the cellar, and wood is a big attraction for vermin.

You may have some insects in your root cellar anyway, but avoiding wooden shelves will decrease their numbers enormously.

You should consider using plastic or metal shelves to store containers because they are a lot more durable and can handle very cold weather.

As for storing your food, there are some ground rules on this matter too: you need always remember the fundamental laws of humidity and choose your containers according to these factors: 

  • Say no to any cardboard or paper packaging in your cellar — it will be wet and destroyed in a matter of days.
  • Use wooden boxes sparingly and use them only for potatoes or other roots.
  • Use plastic or metal containers to store your food and you will never have any problems with them!


Building your underground cellar for storing food is a perfect project for everyone who wants to eat fresh, self-grown, and natural food all year round or wants to stay prepared in the event of a disaster.

Implement the strategies in this guide and you will have the armour to prepare yourself for the long winters and bad weather conditions. You can even hide from hurricanes in your cellar!

It is a perfect place to keep all the canned food you made in summer as well as storing enough fruit and vegetables to feed an army, so to speak!

We hope our guide helps you to build your first underground cellar and saves you a huge amount of time and expense along the way!

We love to hear from our readers, so do get in touch with your underground cellar photos so we can feature them on our website!

About Tom Bell

Hi - I'm Tom, the owner and founder of TheSurvivalSpirit.com! I'm a passionate outdoors enthusiast and am dedicated to bringing you the hottest online survival advice.  


The Survival Spirit is an independent review business. I am not affiliated with any manufacturers and do not accept paid reviews. When you buy through my links, I may earn a commission which helps me to invest in this website and keep producing great content!

About The Survival Spirit

TheSurvivalSpirit.com is run by survival enthusiast, Tom Bell! This website features all of the latest hints and tips on survival, prepping and the great outdoors.

Recommended Articles

Copyright © 2022 The Survival Spirit