Building a Sustainable Shelter Underground to Survive Long Durations

Surviving an apocalypse or disaster of many sorts is much easier with a bomb shelter or safe house. It is even better if your safe house is located underground.  Many people have been constructing their safe house as an underground, hidden shelter.  It is much easier to survive the catastrophe and elements when underground, so long as you still have access to the necessities. 

Human survival essentials will be the first thing to worry about.  In order for you to survive underground you will need a hole that has supported walls and is sustainable.  The body needs water to survive, so access to a clean water system is essential.  Food is also imperative (storing the appropriate canned goods).  Considering there will be food and water, it is ideal to plan a sewage system to ensure sanitary conditions. These systems need to be setup with great care and it is important they are durable; should there be a failure in the water delivery, air ventilation or sewage systems, survival becomes further problematic.

Building your Underground Shelter

There are a lot of considerations when planning your underground build.  Structural integrity is the first important focus, as the walls need to withstand the weight of the Earth around them in order for there to exist a shelter at all. You may want to consider special ventilation which will filter the radiation from the air (this will provide you breathable air in the event of nuclear war). If you are purely worried about a natural disaster or want a safe house as a hiding place, in most cases, it is not necessary to have a radiation filter for the ventilation system.

After you have decided to build your own bomb shelter underground and have selected the prime location for its construction.  This is important, as it means you have decided to forgo a prefabricated shelter or kit, or hiring a specialty company to do the job for you (probably to save money or to ensure that the location is truly 100% private and kept secret).  This means that you must take the considerations and precautions that a contractor or company would have taken to ensure a quality constructed shelter, one which will last and serve its purpose without failure.  Remember, proper planning is everything and disaster can occur any time, year round…so this shelter must be able to support life for your desired duration of time at any time of the year under any condition or circumstance.  Although a shelter might be cold in temperature when it is being constructed or unused, having human inhabitants will cause heat which can build and become rather unbearable.  Although, if the shelter is constructed with proper air ventilation, the health risks from having reduced or poor airflow and restricted oxygen can be eliminated.  The last thing that you want is to die from suffocation after escaping a disaster by ducking into your sweet underground safety pad…that turned out to be a death trap!  When developing the air ventilation it may be wise to consider an air filtration system to remove the radioactive particles from the air in the event the catastrophe is nuclear in nature. 

Important tip: Some form of ventilation is definitely necessary, as otherwise the hole is a grave.


There are two important parts to a basic air ventilation system: the intake and the exhaust piping.  It is wise, for structural reasons and proper flow to plan the pipes at opposite ends of the underground facility.  It is definitely probable however, to ensure the air is flowing with manual manipulation.  The most common way to manually manipulate the flow of air in the shelter is with an air pump.  These pumps can be purchased commercially, or if you are on a budget: constructed at home on your own. Without a doubt, as long as your primary ingredient is determination, you can build your own air pump at home to push the expired air out of the facility and suck clean, fresh air into your shelter. 


A Kearny Air Pump (also known as a KAP) can be constructed relatively quickly and for cheap. These pumps are commonly used specifically to ventilate a shelter like the one you are building (fallout shelters), but it can be used in basically any situation that requires emergency ventilation.  Even with minimal mechanical skills you can construct and use one in your shelter.  This pump requires manual operation to filter the air and is normally only used for emergencies (perfect, right?).  The first appearance of the KAP was in the Nuclear War Survival Skills guide (written by Cresson Keamy).  The construction of a KAP involves pushing air with flaps, filtering the air through the rotation (called a return stroke).  The primary mechanical concept is to create one direction valves that will rotate the air in a single direction, for this reason it is optimal to attach a filter to the intake side.  It is smart to make the filter optional and easily removable, this way it is only necessary when the air actually needs to be filtered and otherwise will refrain from reducing air flow to unbearable lows.

After you have decided your ventilation plan, you must determine how big your underground fallout shelter will be.  The big thing to consider here is “how long will I need to remain in my fallout shelter to survive the disaster?” If it is a temporary shelter, the hole can be much smaller; while more serious disasters (nuclear war, radiation, dust particles in the air, military takeovers, aliens, etc), may require longer durations underground and for this reason, a much larger space.  It may be best to think in terms of a room you currently see in your everyday life and remember to be realistic: digging is not easy.  Another variable which may affect how much volume you decide to dig is how long you have to physically build your shelter. Regardless, select a place that is likely to be dirt all the way down to the maximum depth of your desired hole is essential.  As you dig, be sure to scrape the sides of the walls to remove any dangerous elements (rocks, roots, and other obstructions can be hazards and also sometimes cause unstable walls).  If you remove a large item from your wall, it needs to be replaced with something to ensure the integrity of the wall remains intact.  Generally replacing it with compact clay or dirt will work fine for now.

Once you are satisfied with the size and depth of your underground shelter, it is wise to create support for the walls (this guide is going to assume you have an 8’ x 8’ x 8’ deep hole.  Attaching a tarp to the side of each of the walls, this will help keep the dirt taut against the wall.  Using twelve 2’ x 4’ planks, create 4 triangles.  These triangle supports will be staked into the wall (each wall) and pressed together to create a firm structure (you will need to scale this to match the size of your hole, the triangle supports should be made in sets of 4 and fit perfectly against the wall, stretching from left to right, and ceiling to floor). The stakes should be minimalized, one per triangle, no more than 4 triangles (one per quadrant) for each 8’ x 8’ wall, and if properly measured, part of the support of keeping these supports against the wall will be the pressure caused from pressing the triangles together to fit them against the wall. If you would like to take it one step further, you can fill the inside of the wall with cement by drilling holes through the supports to ensure the cement can properly pour and drill anchors into the supports on the interior side to hold another board, and begin pouring.  Start from the bottom up, so you can ensure all of the gaps are filled.  Some people choose to use stones if they are hurting for time or money, but remember: short changing something like this is always a mistake. Cement is a very wise decision and forming a complete solid set of walls all supporting one another is key to ensuring your shelter will not collapse on you and will be able to support a roof, just pour slowly.  The walls can be designed to be displaced 4 inches on the left each time, allowing the wall to the right to fit in, forming an “infinite loop”.  There are a number of other ways to ensure your walls will not fall down upon you, such as support beams on the inside.   Before you pour any cement, it is best to locate your intake and exhaust locations, and any other ventilation holes you will need.  Most people choose to put these in the roof, given it reduces the strain on wall integrity, however, sometimes going through the wall is imperative…therefore the time to plan is now. 

Now that you are comfortable the walls will not collapse on you, it is time to work on the floor.  Just like a house, you will want a foundation.  A cement foundation is doable, however, a wooden foundation will be adequate for a number of years, it all depends on the level of strength you wish to accomplish. First thing is first though, before you proceed with any foundation plan, it is wise to first do your best to completely level the surface.  Next, laying a few planks of 2’ x 4’ wood parallel to one another, a foot or so apart to line the entire base of the foundation is a good start for a reasonable shelter. Nailing a second set of planks, equally parallel to one another set on top of the first layer of planks in a perpendicular fashion will allow for a premium four inch thick raft (to accomplish this rotate the second set of planks 90 degrees, so that they are making crosses (+ signs) with the first set of planks already on the ground).  Pour cement into the rafts you have just created until you can no longer see the wood and allow the base to dry. 

The roof is important as it will withstand the most impact, be the greatest leak risks (water, radiation, enemy infiltration, etc), and all while needing to be hidden. The roof can be made of a number of things, depending upon how strong you have chosen to construct your shelter. If this is a quicker shelter, or a temporary shelter, wood will do just fine.  If this is a more permanent habitat and meant to help you survive a lengthy apocalypse or disaster, you will need a cement or metal roof and more elaborate valves (for your ventilation and water systems, and also for your entry and exit to your shelter).  It is wise to have a center support beam, especially if you have chosen a heavier roof material or are expecting a long survival period; However, if the underground shelter is large enough, this can very will double as a spiral staircase or other type of ladder. It could also double as one (or all) of your piping and filtration systems.  Regardless, the center support beam will help ensure the roof remains above your head, rather than on your head.  You will want to construct your roof at this stage, however, leave the large part of it unattached (unless it is absolutely imperative to attach it – in which case absolutely take into consideration moving any large equipment or pieces into the shelter which would no longer fit after the roof is in place).  It is important to construct your roof with the necessary valves, piping (air intake and exhaust, waste ventilation, water harvesting, etc), and any other fancy shelter or survival features (radio transmitting equipment, antenna exit holes, other communication or observation technology [such as a periscope], etc).  The roof should be well hidden and blend into the environment with no indicator that it is a detachable unit.  Some people choose to create their hatch with a large stone which they disguise as a “partially submerged” stone, so large in the dirt no one would ever think to move it.  Including a lock will ensure that the stone hatch remains secure.  Additionally, some people prefer specifically to avoid running their piping through the roof, in order to reduce the liability the roof needs to carry (it is already the weakest point of the facility, so to strengthen it, move all of the intake and exhaust piping, all water piping, and any other pipes or utilities, and route them as far away from the facility itself as possible before protruding them from the Earth).  It also makes it easier to blend them into nature this way.


Lower any heavy equipment as well!

Now you will want to make it look pretty (if you so desire).  It is not necessary to proceed with this part if you are building a temporary or more hastily constructed shelter.  This step will make the shelter feel a little more like home if you are planning a longer stay, and that goes a long way in keeping a person sane.  Pre-drill metal anchors into your wall, ensuring to drill into the center of the 2’ x 4’ planks which are creating your triangle supports (at this point you may have already poured concrete into the wall, which is great, otherwise, you will not be pouring after you put the sheetrock up, so if you have not poured your concrete yet into the wall supports, do so first).  Ultimately, you are going to lower each sheetrock one by one, pre-measured for the anchor holes you just drilled into your supports, and fasten the sheetrock slabs to the wall.  It is suggested to avoid paint of any kind considering this will be a confined space and you may need to inhabit it for long durations.  Avoid using wallpaper and always be sure to buy flame-retardant materials to the best of your ability, and materials free of chemicals (this includes doing your best to avoid chemical treated lumber).

A Few Extra Words Regarding Ventilation

It is important to understand that what may feel like a cold, safe shelter in the beginning, may produce a hot, unbearable and dangerously humid shelter upon human occupancy.  This is especially true the more people in your square footage.  It is important to plan for the appropriate amount of people the shelter is expected to harbor. The body will give off a lot of heat and water vapor through sweat and the more crowded the worse it will get. It is absolutely essential that the ventilation is appropriate for the shelter and number of occupants. The ventilation should be equipped to adequately move the air through the facility and be capable of removing fallout particles and/or radiation from the air, making it once again breathable on the inside. Directional fanning is a very common and adequate form of moving air through bomb shelters and other underground emergency saferooms and facilities.  A KAP pump can be constructed in an emergency out of common household materials simply by scavenging…however, a quality pump will be required in order to survive longer durations.  Remember, the longer the expected survival duration, the higher quality KAP you will want to use.  Although some good homemade pump can survive 1000 hours or more of operation, it is ideal that it is made to last much longer. There are some reasonable youtube videos which can explain how to craft your own Kearny Air Pump, however, purchasing a commercial air pump may be your best bet if you want your shelter to uphold the worst conditions and provide the most stable living environment in any emergency situation. 

Tip: Your ventilation filters should be capable of handling all NBC threats (Nuclear, Biological, and Chemical) in the air.  Common commercial HEPA filters will collect fine particles but not everything.  It is advisable to construct or purchase a 3 layer filtration device: the first layer being a pre-filter can collect the largest particles, followed by a HEPA filter and then followed by a carbon filter to absorb any toxic particles. It is important to attach your filter to the intake side of your ventilation system, not the exhaust end.


How to get Water to your Underground Shelter

It is important to consider all things while planning your underground shelter build, however, one of the most imperative considerations for survival is fresh water delivery.  Without water, surviving underground is only realistic for a matter of a few days (although there are reports of people having survived up to a week without water, it is not optimal and certainly threatening).  It is imperative to consider a fresh water delivery system for your shelter, and depending upon where you live, it may be easier or harder.  In some locations, storing water will be your only reasonable option, which means in-shelter storage jugs, or a larger pre-buried storage tank. 

Should you choose to build a rainwater harvesting system, please bear in mind: if the catastrophe which has caused you to retreat to your shelter involves any air pollutants (nuclear war, radiation or chem trails of any kind, fallout particles from explosions), you will not want to use your harvesting system, and will need to ensure it is shut off from polluting your water storage tank.  Remember that nuclear threats and even nearby radiation can collect in clouds, even travel long distances, causing the rainwater to be dangerously toxic (actually cancerous).    It is very easy to create a harvesting system otherwise, as long as you dig extra volume for your underground water tank. You do not want to leave a water tank or anything of the sort above ground, as it may indicate to nearby threats that there is a human habitat nearby, from there it’s as easy as following the pipes.  Staying hidden is essential, so ideally, you’ll want to also route your pipe a little distance away from your facility and protect the opening by disguising it into nature best possible.   Building a vessel to collect the water above ground is sometimes best hidden in a sand pit. Sand acts as a natural filter and will remove large particles from the water, while your vessel (leading to your piping) can remain within the bottom of the sand pit.  As long as gravity is taken into consideration when you bury your piping (bury the piping with a gradient decline, connecting the lower end at the facility end, and the water will naturally collect in the vessel and flow through the piping.  It is common for the vessel to be funnel shaped, or shaped much like a gutter on a roof, with some mesh screen to prevent sand and large particulates from entering and clogging the piping.  It is wise to keep a snake in the shelter with you (long flexible, yet still sturdy wire), which you can use to help clear any clogging from within.  Your carbon filter or any commercial filter you choose to use, should be built into the facility end, not the Earth end; this way if you are trapped for a while, you can change your filter as needed without exiting the shelter.  Your tank can be accessible from the inside of the facility, and connect after the filter. There are many ways to harvest rainwater, creativity truly becomes a valuable asset in building an appropriate harvesting device for your facility.  It is also important to consider the appropriate tank for collecting and holding water for long durations of time.  Some suggest installing a dual tank system, so that you can more easily clean your tanks and reduce contamination and mold as much as possible.  Mold is the last thing you want entering your fallout shelter. You should calculate your tank size based upon the number of persons you expect to harbor, maximum duration your shelter will be viable for surviving within, and the amount of water the persons inside will consume in order to remain healthy (the average man requires 3 liters of water a day, while the average woman requires 2.2 liters a day).  Having two tanks will allow you to clean your tanks whenever you would like, without sacrificing any of your water (important especially in areas which frequently suffer dry spells). Your containers should not be open, but closed and made of a reasonable material.  Polyethylene, ferrocement, and fiberglass are commonly used (polyethylene commonly used in commercial models sold online all the time). Always consider installing an overflow or bypass system to prevent damage or contamination problems arising from overflow water or blockages. When considering where to dump any overflow, remember that having pools of flooding water may lead people to your overflow pipes, so ensure to plan accordingly and avoid any flooding puddles or water visible build up above ground.

Please remember: Harvesting rainwater is illegal in some ordinances. If your catastrophe is not truly end-of-the-world in nature, please remember the rules and laws in your local area when building a Conveyance system.


How and What to Eat Underground

Sustenance provides energy and energy is required for survival.  Depending upon your circumstance and personal catastrophe situation, the amount of energy you will need may vary. For instance, to survive a nuclear attack, you will want to remain underground for a longer duration, months (maybe even years), and will require little energy to operate each day.  Your catastrophe may require you to remain fit, forcing you to work out each day, in which case more energy will be required each day.  No matter the scenario, your shelter should be equipped to help you survive a number of disasters from nuclear wasteland to hostile military takeover.

Being well versed in nutrition is a huge plus.  Rather than attempting to memorize everything there is to know about nutrition, stocking a few guides and reviewing them ahead of time in order to stock the appropriate food rations is adequate.  If you are going to include a garden in your underground shelter, you will want to take nutrition into consideration when planning your seeds and growth cycles.  If you are relying purely upon stored rations, including all of the necessary vitamins and minerals your body needs to survive long durations is essential. It is very difficult to live without food for extended periods of time and will cause all types of mental insanity, so plan your rations to last the appropriate time period you will inhabit the facility.  If you know that your survival duration requirements will be lengthy, you will want to create a garden, while shorter durations will make survival purely from emergency food supply and rations more feasible. Remember, prepping for an emergency involves more than just emergency food supplies, if the emergency is going to become ongoing.


Waste Disposal for an Underground Shelter

The longer the duration of inhabiting a fallout shelter, the more of a problem waste will become.  Waste disposal includes both garbage and human waste.   Urine is much simpler to deal with than feces, but there will need to be a plan for everything (especially the longer you plan to stay).  If this is a temporary shelter and the duration is guaranteed to be shorter, a few 5 gallon buckets lined with trash bags should do.  Some people suggest using cat litter to line the feces each time to help cover up the odor, however, in between use the lids must be securely fastened.  Ventilation is an issue in tight spaces, even with a proper air pump, defecating within the shelter creates major sanitation issues.  If you have the luxury of planning a more adequate shelter, it is advised to create a section or room specifically for defecation, considering extra ventilation for this area.  Higher quality shelters built for longer duration and durability should be more clever and space-friendly to make enduring the stay easier during a defecation session.  First, there is the issue of urine.  Urine being a liquid, is easier to manage and can be recycled more simply into the shelter.  Installing a third water tank, a special water tank and device, could allow urine to be recycled.  The astronauts have developed a system for reusing shower water and urine by filtering the urine waste through osmosis.  Reverse osmosis filtration will remove contaminants and/or distillation (NASA’s system uses a special membrane and a sugar solution).  Distillation will require heat, heat will require extra types of ventilation, and create further liabilities.  However, urine has been known to be able to do a number of things if creating an osmosis filtration or distillation system is too complicated or not possible.  Collecting urine in a separate tank of its own will still allow you to control and recycle this waste.  It is also wise to pass all urine through a series of UV lights, which will kill microbes (a plus to stay on top of no matter what you do with it).  If you are producing any type of vegetation or have a garden in your facility, urine is a strong growth booster and will help grow your plants and vegetables tall and healthy in size. If you have not considered an underground garden system (which can be started after a crisis if you properly prepare and stock the right materials and seeds), please consider routing sunlight and/or bringing artificial sunlight…as plants are very advantageous to underground survival.  Urine has also been known to run generators…that’s right, you can actually modify a generator to be powered by urine (VERY advisable for any underground shelter, if you can find a quiet generator and have the time to build a space to support it which will help drown out the motor sounds as to prevent above ground by-passers from locating you based upon sound).  Human waste can be reused as fertilizer, however, not all of it is required and it may cause a problem to use waste as fertilizer underground without top notch perfect ventilation for your garden area and is ill-advised without expert planning.  Regardless, not all of it would be able to be used here, so another system is required.  A very technical use of human waste, biogas production, can actually produce enough electricity to power your underground shelter.  A biogas digester works to collect methane produced by the microbes present in human feces inside an air tight container, which can then be channeled to generate electricity.  It is important that the system is airtight, as oxygen is deadly to the methane-producing microbes. There are many other ways to generate electricity and power from methane and human waste, however, some prefer a system for disposal and wonder how to get rid of the human waste in their underground bomb shelter. One way of getting rid of the solid waste is a powerless and waterless composting toilet and there are several environmentally friendly options available on the market.  It is also possible to burn it, if you have built an appropriate crematory with a chimney and a one-way valve to push the toxic air out of the facility, without allowing any unfiltered air into the facility in the process.  This must be tested thoroughly and not just by inhaling air while operating your chimney system…however, by actually testing the toxicity in the air.  You do not want to burn your waste if ANY of it will build up inside the shelter. All of the waste smoke and air must be pushed out of the facility.


How to Get Sunlight to your Underground Shelter

It is possible to live an extremely long time without sunlight, however, not without repercussions. Deprivation of sunlight can lead to a weakened immune system and increased vulnerability to an array of chronic diseases and illness. This includes more common disease and conditions, such as high blood pressure rickets, and diabetes.  A lack of Vitamin D will reduce calcium absorption and lead to a number of further complications (spasms in the larynx and even suffocation have been reported).  Pro-longed deprivation can even lead to heart disease. Human beings need sunlight for a proper and well balanced survival, which can be tough in an underground facility. 

One answer is to route sunlight into your chamber, which is certainly easier said than done, however still possible. Sometimes this is known as a “light tunnel” or “sun tunnel”, and may use aluminum, large mirrors, or other reflective materials to channel the sunlight into the facility.  With a lot of creativity, light can be routed from rather far away.  Another, less labor intensive method of bringing sunlight into your underground fallout shelter, is artificially. There are commercial light bulbs which can emit various spectrums of light which can imitate various parts of the sun. In order to accomplish this, the lights will need to also produce infrared and ultraviolet lights.  There are Vitamin D lamps specifically intended for developing vitamin d and simulating the UV of the sun.   And finally, of course, there are vitamin D supplements (capsules which can be taken – though these will not truly replace the sun, they will help).

Caution: Be very careful and plan properly when purchasing bulbs for sunlight simulation…bringing some bulbs in will come with extra liability, from the gas inside the bulbs and fire hazards, to skin burns from incorrect light intensities.


Preparing Your Underground Shelter is Sensitive


Building your own fallout shelter (bomb shelter or otherwise underground safe room), is one of the most important tasks of being prepared for anything and one of the ultimate holy grails of survival. A proper construction includes a proper plan.  A good survival tip: keep your shelter location and existence a secret. There is no need to create extra liability of looters and freeloaders who haven’t put in the time and work to build the shelter. Everyone will want in on your plan after your shelter becomes needed, and if you have kept your shelter as a “need to know” basis, you will be able to survive with the planned rations and have no shortages.  Your shelter is also built to support a specific amount of people, the people you preplan to support…having more people will put a strain on more than just the rations and water, however, the air ventilation system (which is far problematic)!


Survivalist Tip: Keep your underground shelter a secret and hidden at all costs!

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