Storm Cellar Construction: Tornado Alley Safety & Cost Guide
Are you worried about the next tornado barreling through Tornado Alley? The peace of mind that comes with having a safe place to ride out the storm is priceless. This article will guide you through the entire process of building your own storm cellar, from initial planning to final construction, ensuring your family's safety and security.
Planning Your Storm Cellar Project
The first step in building a storm cellar is meticulous planning. This involves assessing your needs, choosing a suitable location, and understanding local regulations. Neglecting this phase can lead to costly mistakes and potential safety hazards.
- Assess Your Needs: Determine the number of people the cellar needs to accommodate, including pets. Consider accessibility for all family members, including those with mobility issues. Think about the duration you might need to stay in the cellar (e.g., bringing supplies for 24-72 hours).
- Choose a Location: Select a site that is easily accessible from your home, preferably within a short distance. Avoid areas prone to flooding or with unstable soil conditions. Consider the water table level. An ideal location is slightly elevated and well-drained.
- Understand Local Regulations: Research local building codes and permit requirements. Contact your city or county's building department to inquire about specific regulations related to storm cellar design and construction. Failure to obtain necessary building permits can result in fines and delays.
Storm Cellar Design and Construction Methods
Selecting the right design and construction method is crucial for ensuring the structural integrity of your underground bunker. Several options exist, each with its own advantages and disadvantages.
Choosing the Right Design
Consider these design options:
- Pre-fabricated Cellars: These are typically made of fiberglass or concrete and are installed as a single unit. They offer ease of installation and consistent quality control. However, they may be limited in size and customization options.
- Poured Concrete Cellars: These are built on-site using reinforced concrete. They offer superior strength and durability and can be customized to fit your specific needs. However, they require more labor and expertise.
- Concrete Block Cellars: These are constructed using concrete blocks filled with reinforced concrete. They offer a balance between cost and durability but require careful construction to ensure structural integrity.
Construction Steps for a Poured Concrete Storm Cellar
- Excavation: Excavate the site according to your design specifications. Ensure proper sloping for drainage.
- Formwork: Build the formwork for the concrete walls and roof. Use reinforced steel to create a strong framework.
- Pouring Concrete: Pour the concrete into the formwork. Use a concrete mix appropriate for underground construction. Ensure proper compaction and curing.
- Waterproofing: Apply a waterproof membrane to the exterior of the concrete walls to prevent water infiltration.
- Backfilling: Backfill the excavated area around the cellar. Compact the soil to prevent settling.
- Entrance Construction: Build the entrance to the cellar. Ensure it is secure and weather-tight. Include a sloped entrance for easy access, if possible.
- Ventilation: Install proper ventilation to prevent the buildup of gases.
Ensuring Safety and Compliance
Safety is paramount when building a FEMA storm shelter. Adhering to safety guidelines and ensuring compliance with regulations will protect you and your family during a tornado.
According to a 2022 FEMA publication (P-361, "Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms"), a safe room must be able to withstand winds of 250 mph.
- Structural Integrity: Ensure the cellar is structurally sound and capable of withstanding extreme wind pressures. Consult with a structural engineer to verify the design.
- Ventilation: Provide adequate ventilation to prevent the buildup of carbon monoxide and other harmful gases. A passive ventilation system is usually sufficient.
- Emergency Supplies: Stock the cellar with essential supplies, including water, food, first-aid kit, flashlight, and a battery-powered radio.
- Accessibility: Ensure the entrance is easily accessible, even during severe weather. Consider a ramp or steps with handrails for those with mobility issues.
- Communication: Have a way to communicate with the outside world, such as a weather radio or a cell phone.
Cost Considerations and Financing Options
The tornado shelter cost can vary significantly depending on the size, design, and construction method. Understanding the cost factors and exploring financing options can help you budget effectively.
Cost Breakdown
Here’s a table illustrating typical cost ranges for different types of storm cellars:
| Type of Storm Cellar | Material Costs | Labor Costs | Total Estimated Cost |
|---|---|---|---|
| Pre-fabricated Cellar | $3,000 - $8,000 | $1,000 - $3,000 | $4,000 - $11,000 |
| Poured Concrete Storm Cellar | $5,000 - $12,000 | $3,000 - $8,000 | $8,000 - $20,000 |
| Concrete Block Cellar | $4,000 - $10,000 | $2,000 - $6,000 | $6,000 - $16,000 |
These are approximate figures, and the actual cost may vary depending on your location, specific design requirements, and the contractor you choose.
Financing Options
Explore these potential funding sources:
- Personal Savings: Using your own savings is the most straightforward option.
- Home Equity Loan: A home equity loan can provide access to funds at a relatively low interest rate.
- Government Storm Shelter Grants: Check with your state and local emergency management agencies for potential grant programs.
- FEMA Assistance: In some cases, FEMA may offer assistance for safe room construction after a disaster.
Above Ground Shelter vs. Below Ground Storm Cellar
While this article focuses on below-ground cellars, it's important to consider the alternative: above ground shelter or safe room. Above-ground safe rooms are constructed within your existing home or as a detached structure. They offer quicker access and may be easier to build for some homeowners. However, they can be more expensive and may require more extensive renovations. Consider the pros and cons of both options before making a decision.
Troubleshooting and Pro Tips
- Water Infiltration: Ensure proper waterproofing to prevent water from seeping into the cellar. If water infiltration occurs, address the source of the leak and apply a sealant.
- Ventilation Issues: If the cellar feels stuffy or humid, improve ventilation by adding additional vents or a small fan.
- Pest Control: Regularly inspect the cellar for pests and take appropriate measures to control them.
- Emergency Plan: Develop a family emergency plan that includes clear instructions on how to access and use the storm cellar. Practice the plan regularly.
Pro Tip:
Always keep a battery-operated NOAA weather radio in your storm cellar to stay informed about the storm's progress and any potential changes in the forecast. This is especially important if your cellar does not have cell phone reception.
FAQ
- Do I need a permit to build a storm cellar?
Yes, in most areas, you will need a building permit to construct a storm cellar. Check with your local building department for specific requirements.
- How deep should a storm cellar be?
The depth depends on the design and local soil conditions, but generally, the top of the cellar should be at least several feet below the frost line to prevent freezing.
- What size storm cellar do I need?
The size depends on the number of people and pets you need to accommodate. A general rule of thumb is to allow at least 5 square feet per person.
- What should I do if my cellar floods?
Ensure your electrical systems are shut down and avoid contact with the water until power is disconnected. Pump out the water. Identify and repair the source of the flooding. Disinfect the cellar thoroughly.
Building a storm cellar is a significant undertaking, but it's an investment in your family's safety and peace of mind. By following these steps and seeking professional guidance when needed, you can create a safe haven to protect you from the dangers of Tornado Alley. Do you have any questions or experiences to share? Leave a comment below – your insights could help others!