Before You Buy A Tornado Shelter: 15 Questions Every Homeowner Should Ask

Buying a tornado shelter is different from buying almost anything else for your home. You are not simply comparing price, appearance or convenience. You are choosing a product that may someday be called upon to protect your family during one of nature's most violent events.

That makes the questions you ask before purchasing every bit as important as the shelter you ultimately choose.

Who actually manufactures the shelter? What was tested? Who performed the testing? Who engineered it? Who installs it? What happens if something goes wrong years from now? And who will still be standing behind the product when you need help?

This guide was created to help homeowners evaluate any tornado or storm shelter—not simply the Granger ISS. An informed homeowner should be comfortable asking difficult questions of every manufacturer, dealer and installer competing for their business.

Why Choosing a Tornado Shelter Deserves More Homework

Tornado shelters are life-safety products. Yet homeowners may encounter dramatically different products, materials, manufacturers, dealers, installation methods, warranties and marketing claims while shopping.

Two shelters can look similar in an online photograph while having very different histories behind their design, engineering, testing, construction and installation.

Price matters. But the lowest initial price is not necessarily the most important question when evaluating a product intended to remain at your property for years or decades.

The better question is: What exactly am I buying, who is responsible for it, and what evidence supports the claims being made?

First, Understand What “FEMA Approved” Really Means

This is one of the most important things homeowners should understand before comparing storm shelters.

The Federal Emergency Management Agency provides extensive guidance for the design and construction of safe rooms through publications including FEMA P-320 and FEMA P-361. FEMA guidance also references the ICC/NSSA 500 Standard for the Design and Construction of Storm Shelters.

However, FEMA does not endorse, approve, certify or recommend individual tornado shelter products, manufacturers or contractors.

That means a phrase such as “FEMA approved” should prompt additional questions.

Instead, ask exactly what the seller means:

• What FEMA criteria are being referenced?
• What testing was performed?
• What component or shelter design was tested?
• What edition or standard is being referenced?
• Who performed or witnessed the testing?
• Can you see the documentation?

Learn more directly from FEMA's Safe Room resources and the 2023 ICC/NSSA 500 storm shelter standard.

15 Questions to Ask Before Buying a Tornado Shelter

1. Who Actually Manufactures the Tornado Shelter?

Start with one of the simplest questions—and one that is surprisingly easy to overlook.

Is the company taking your money the manufacturer, a dealer, an installer, an online reseller or some combination of those?

There is nothing inherently wrong with purchasing through a qualified dealer or installer. Many manufacturers rely on professional dealer and installation networks.

What matters is knowing who actually manufactured the shelter and who ultimately stands behind it.

2. How Long Has the Manufacturer Been in Business?

A warranty is only as useful as the organization responsible for honoring it.

Ask how long the manufacturer has operated, where the product is manufactured, whether the company has an established facility and whether you can contact the manufacturer directly.

A storm shelter can remain with a home far longer than many ordinary consumer products. Long-term support deserves consideration before purchase.

3. What Is the Relationship Between the Manufacturer, Dealer and Installer?

Know who is responsible for each part of the transaction.

Who takes the order? Who receives the payment? Who delivers the shelter? Who excavates or prepares the installation site? Who installs the shelter? Who handles a warranty issue?

Get those responsibilities in writing whenever possible.

4. What Design Criteria or Storm Shelter Standards Are Being Referenced?

Ask the company to explain its claims in plain language.

ICC/NSSA 500 establishes minimum design and construction requirements addressing numerous aspects of a storm shelter—not just one component. FEMA publications provide additional safe-room guidance.

A knowledgeable company should be willing to explain which standards, engineering criteria and testing protocols are relevant to the shelter being offered.

5. What Debris-Impact Testing Has Been Performed?

Wind-borne debris represents a major hazard during violent tornadoes. Debris-impact resistance is therefore a critical consideration in storm shelter design.

Don't stop at the word tested. Ask what was tested, where the testing was performed, what criteria were used and whether you can see the evidence.

Below is footage from debris-impact testing performed on the Granger ISS Tornado Shelter door at Texas Tech University.

Ask:

• What was tested?
• What test protocol was used?
• Where was the test performed?
• What projectile or missile criteria were used?
• Did the tested configuration match the product being sold?
• Can you review documentation or video of the test?

6. Was Only the Door Tested—or Has the Overall Shelter Design Been Evaluated?

Door performance is extremely important, but a storm shelter is a system.

Structural design, connections, openings, ventilation, entry and egress, installation and other factors can all matter.

A debris-impact test should not automatically be interpreted as proof that every aspect of a shelter design has been independently evaluated.

Ask exactly what the available documentation establishes.

7. Is Engineering Documentation Available?

Marketing language should not replace engineering.

Ask whether engineering drawings, calculations, test reports or other supporting documentation exist for the shelter design.

You may never need to personally analyze an engineering report, but a manufacturer should know what technical documentation supports its product.

8. What Is the Shelter Made From?

Material selection affects much more than appearance.

Depending on the shelter, construction may involve steel, concrete, composites, polyethylene or combinations of materials.

Ask how the chosen materials perform in the environment where the shelter will spend its life.

For an underground shelter, that can include continuous contact with soil, moisture, groundwater and changing temperatures.

Ask about corrosion, water exposure, cracking, deterioration, maintenance and expected long-term performance.

9. How Does the Design Address Soil, Water and Installation Conditions?

No homeowner should assume that every property presents identical installation conditions.

Soil type, drainage, groundwater, access, buried utilities, excavation conditions and local requirements can all influence an installation.

Ask what site conditions must be evaluated before work begins and whether the manufacturer provides documented installation instructions.

10. Can Everyone in Your Household Enter and Exit the Shelter?

A shelter that is difficult for a household member to access may not be the correct shelter for that family.

Consider children, older adults, people with limited mobility and pets.

Evaluate steps, ladders, handrails, door weight, opening mechanisms, interior space, lighting and the ability to exit after the storm.

Don't merely look at the shelter from the outside. Ask to see how people actually enter and leave it.

11. Who Is Responsible for the Installation?

Excellent product design can be undermined by an improper installation.

Ask whether installation is performed by the manufacturer, an authorized dealer, an independent excavation contractor or another party.

Ask what training or instructions installers receive and who verifies that the completed installation follows the manufacturer's requirements.

12. Are Permits, Inspections, Foundations or Anchoring Requirements Involved?

Requirements can vary according to shelter design and jurisdiction.

Never assume that what worked at another property automatically applies to yours.

Ask the manufacturer or installer what the product requires and check with the appropriate local building authority when necessary.

13. What Does the Warranty Actually Cover?

“Lifetime warranty” sounds reassuring, but the details matter.

Ask:

• Whose lifetime defines the warranty period?
• Is the warranty transferable?
• Which components are covered?
• Are material defects covered?
• Is water intrusion covered?
• Is the door covered separately?
• Is labor included?
• Are there installation exclusions?
• Who pays transportation or replacement costs?

Read the actual warranty rather than relying solely on advertising language.

14. What Happens If You Need Service Years From Now?

Think beyond installation day.

Can the door hardware be serviced? Can components be replaced? Can you obtain replacement parts? Can you reach the manufacturer directly?

And one of the most important questions:

If the dealer or installer that sold you the shelter is no longer in business, who do you call?

15. What Are the Payment, Scheduling and Refund Terms?

Before transferring a significant deposit or full payment, understand the transaction.

Ask for a written quote or contract identifying the shelter, price, installation scope, estimated schedule, payment terms and any cancellation or refund provisions.

Be cautious when a seller pressures you to make a substantial immediate payment without clearly documenting what will happen next.

Storm Shelter Red Flags Worth Investigating

One unusual answer does not automatically mean a company or product is untrustworthy. But certain situations should prompt additional questions.

• “It's FEMA approved.” Ask exactly what that means and request documentation.
• “It's tested.” Ask what was tested, where, how and against what criteria.
• The actual manufacturer is difficult to identify. Find out who built the product.
• Technical documentation is unavailable. Ask what evidence supports the safety claims.
• The warranty sounds impressive but isn't available in writing. Read it before purchasing.
• A large payment is requested without clear written terms. Know what you're paying for and what happens if the installation does not occur as expected.
• Installation requirements are treated as an afterthought. Installation is part of the shelter system.

Compare More Than the Price

When comparing tornado shelter quotes, create an apples-to-apples comparison.

A lower quote may exclude delivery, excavation, installation, permits or other work. A more expensive shelter may include features, materials, warranties or support that another does not.

There is nothing wrong with asking a manufacturer to explain why its product costs more—or less—than another option.

An established manufacturer should welcome an informed customer.

About the Granger ISS Tornado Shelter

The Granger ISS Tornado Shelter has been manufactured by The Granger Plastics Company for more than two decades.

Granger Plastics is an established rotational molding manufacturer located in Middletown, Ohio, with more than three decades of manufacturing experience across demanding commercial and industrial applications.

The Granger ISS uses rotationally molded polyethylene construction with a double-wall, foam-filled body and incorporates molded steps, seating, handrails and a multi-layer entry door. The shelter's door has undergone debris-impact testing at Texas Tech University.

You can explore the features of the Granger ISS Tornado Shelter, watch tornado shelter testing and installation videos, or learn more about the company behind the Granger ISS.

We believe homeowners should ask hard questions before purchasing a storm shelter.

And we believe manufacturers should be prepared to answer them.

Frequently Asked Questions About Buying a Tornado Shelter

Does FEMA approve tornado shelters?

FEMA states that it does not endorse, approve, certify or recommend individual contractors, firms or products. FEMA publishes safe-room guidance, and homeowners should ask manufacturers to explain exactly what testing, engineering criteria or standards support their individual product claims.

What is ICC 500?

ICC/NSSA 500 is a consensus standard establishing minimum design and construction requirements for storm shelters intended to provide refuge from tornadoes, hurricanes and other extreme-wind events.

Is debris-impact testing important?

Yes. Wind-borne debris is a major tornado hazard, making impact resistance a critical consideration. Homeowners should ask what was tested, the criteria used and whether the tested configuration corresponds to the product being purchased.

Should I buy directly from a manufacturer?

Not necessarily. Qualified dealers and professional installers can provide excellent service. What matters is understanding who manufactured the shelter, who is responsible for installation, who supports the product and who will honor the warranty.

Should price be the deciding factor?

Price should be considered alongside design, testing, materials, installation, warranty, manufacturer history and long-term support. A storm shelter is a life-safety purchase, making total value more important than price alone.