How it works
A garage floor shelter is a heavy steel box installed in a pit under your garage slab. The top is a steel lid that slides open on rails, usually with a manual mechanism and sometimes with an electric opener and manual backup. When it's closed, the lid sits flush with the floor and you can usually drive over it.
The installation
- Site check. The installer looks at your slab, the garage layout and where vehicles park, and arranges a Texas 811 utility locate.
- Cut and dig. A section of the slab is saw-cut and removed, and the pit is excavated. Caliche or rock may need extra equipment.
- Set and anchor. The shelter is lowered in, leveled and anchored.
- Re-pour. Concrete is poured around the shelter to tie it into the slab.
- Finish. The lid, seals and any opener are adjusted and tested.
Many installs are done in a day, followed by concrete curing time before heavy vehicles go over the area.
Sizes and capacity
The ICC 500 standard requires at least 3 square feet of floor area per person in a residential tornado shelter. Common sizes seat roughly 4 to 12 people. Plan for your household plus anyone who might shelter with you, and leave room for a weather radio, flashlight, water and medications.
Pros
- Reach it without going outside
- Takes up no usable space when closed
- Below-ground position adds protection from debris
Things to plan for
- Parking. You can't open the lid with a vehicle on it. Think about where cars sit during storm season.
- Steps. Getting in means climbing down steps, which can be hard for some people. An above-ground safe room may be better for them.
- Getting out. If debris covers the lid, you may need help to get out. Register your shelter with local emergency management, and keep a phone and weather radio inside.
- Water. A good install includes proper sealing at the lid and attention to drainage.
Questions to ask
- Is the exact model, including the lid and locking hardware, tested to ICC 500 / FEMA P-361?
- Is the manufacturer NSSA-verified?
- How is the shelter ventilated?
- Can it be opened from inside without power?
- Who handles permits, and what warranty is offered?