Brent Sr. and his family are "preppers" - people who are preparing for the end of the world. And although their lifestyle may seem crazy to some (they are building a castle, after all), what they really want to do is get the word out so other people are ready too.

Brent Sr. (whose last name is being withheld for privacy), begin prepping for the "end of days" in 1999 in anticipation of Y2K. The former aeronautical engineer and Army infantry training officer has since enlisted the help of five of his 10 children to work on his "Doomsday Castle" in the event that one day the world will face an Electro Magnetic Pulse (EMP) in which the power grid completely shuts down.

The castle is located in an isolated area in the Carolina Mountains. Over the course of four months, Brent Sr. and his kids combined their efforts to make the place ready for the "end of days."  

The patriarch explained that his message is worth the exposure the family will face by appearing on television. The more people who learn survival skills, the better it is for everyone else. His 20-year-old son Michael noted, "We're building a community of preppers."

In the first episode of "Doomsday Castle," airing on National Geographic on Aug. 13, dad surprises his family by concocting a castle invasion. Twenty masked marauders raid the property to see how the family responds.

"Everybody panicked," Brent Sr. said. None of his five children – Brent Jr., Ashley, Lindsey, Michael or Dawn-Marie - escaped from the chaos.  But don't worry - they redeem themselves by the end of the series.

Doomsday Castle - Welcome to the Castle

What can the average person do in a doomsday scenario?

Most people don't have the means to build a Doomsday Castle, but there are plenty of things the everyday citizen can do to prepare for Armageddon – or even for something on a smaller scale such as a hurricane.

Dawn-Marie, 20, who works in a nursing home and takes care of her young son, insists "there's a little prepper within everyone."  She wants viewers to know that her siblings aren't "spoiled brats in a castle." And just because she and her sisters are pretty, doesn't mean they aren't tough.

Dawn-Marie advises burgeoning preppers to begin with canning to preserve food and keep it from spoiling. She also recommends creating a backyard garden with fruits and vegetables.

People should also save things that may be useful in the future. For example, Brent Sr. kept an old dresser that was later turned into a chicken coup and a stove that was made into a smoker. Dawn-Marie advises that people visit yard sales and thrift shops to pick up items such as jars for preservation, clothes, baby items and other basic essentials.

And if and when Armageddon hits, there are simple and cost-effective ways to protect your property by setting up a perimeter fence with booby traps and snares as well as an alarm system made from telephone wire. "There's a lot you can do with what you already have," Dawn-Marie noted.

Essentially, there are four things a person needs in a doomsday scenario: water, food, shelter and protection.  Survivor Jane, a blogger and friend of Brent Sr. and his family, advises that people do the following:

1) Have on hand one gallon of water for each person for each day.  Buy bottled water, harvest rain water, store containers of tap water, or use the water from a pool or hot water heater if necessary.

2) With a grill and cooking source you can cook just about anything. Rice, beans, and pasta can be made into a myriad of dishes. Eat dehydrated fruits. Don't just store food – put new food in the back and use the one in front so you can keep track of what you use and see what is getting low.

3) Prepare your home by having sand bags ready, plywood on standby for windows, and tree limbs pruned. Have alternative places to go with a "bug out" bag that includes food, water, clothing and first-aid supplies. Camp out if necessary.

4) As for protection, firearms are good, but you can also get by with an item like wasp spray, which can shoot a 20-foot stream of foam into someone's eyes. To avoid looters and rioters, make your home appear "visited" by throwing trash into the yard, painting scorch marks on the windows, or painting a sign that says "Looters will be shot."

"Doomsday Castle," a spin-off of "Doomsday Preppers," premieres Tuesday, Aug. 13 at 10 p.m. ET/PT on National Geographic.

Dawn-Marie aims a crossbow, which can be used for hunting and self-defense