Can You Have A Basement In A Flood Zone?

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Basements are beneath the ground level of a house. If your property is in a flood-prone area, you might hesitate to use your basement. There is a high possibility of damage that can waste your resources. To help you decide wisely, we have consulted the experts if you can have a basement in a flood zone.

It is possible to have a basement even in a flood zone. You need to check your location's flood risks and state building requirements first. There are preventive measures to help you minimize the damages brought by flooding. You can improve drainage systems and foundations and apply waterproofing methods.

Other things to consider include insurance agreements, permits, and the foundation of the basement. Remember that calamities like a flood occurs naturally and are uncertain. That is why you should prepare for the effects of flooding. Read further to learn how you can reduce the damage of flooding in the basement.

Photo of a modern house with basement in a flood zone area, Can You Have A Basement In A Flood Zone?

Identifying Flood-Prone Areas

Flooding can wreak havoc on your basement. You might not be able to do your usual activities. If you do not take the precautions to tackle the hazards of flooding, you can incur costs for repairs and replacements. Aside from monetary issues, you might endanger lives and lose your property.

The Federal Emergency Management Agency (FEMA) defined four major flood zone classifications. The zones have varying flood level risks and flood insurance requirements. For areas in flood zones, there are specific ordinances and building codes to follow. Below is the list of flood hazard areas:

  • Special - This category includes V and A zones, wherein the properties are at risk of high flooding. The locations in this zone are near the coast, lakes, rivers, and other bodies of water. Most sub-zones in this category will need flood insurance.
  • Moderate - The floodplains in this zone have a moderate risk of flooding. These areas are between 100 to 500-year flooding. This category includes shaded X and B zones.
  • Minimal - There is a low risk for flooding, and insurance is not mandatory in this zone.
  • Undetermined risk - There were no studies about flooding done in this area. So, the risk of flooding is uncertain.

You can refer to the FEMA flood map service center to know if your place is at risk of flooding.

You can still build your basement as long as you apply preventive measures. It will also help if you buy durable and waterproof materials for the basement. Insurance is also important when deciding to build in a flood zone.

Always refer to professionals or your state building office to guide you in constructing the basement.

Is Flood Zone AE Bad?

The AE classification is under the high-risk flood zone. Areas that are low-lying and near bodies of water like lakes and streams are in this category. There will be different sources of flooding in various AE zones in the United States. The NFIP requires homes with mortgages to get flood insurance for their properties.

Here are the requisites from the American Society of Civil Engineers for AE flood zones:

  • The height of the lowest floor structure (like the basement) should be at or above the BFE. The BFE of AE zones is at least 8 feet.
  • You cannot use the enclosed areas below the required BFE as a living space.
  • Elevate the electrical and plumbing connections, as well as the HVAC system above the BFE.

You can improve your structures to follow the standards required by your state.

What Foundation Type Is Best Suited To A Flood-Prone Site?

Waterproofing protection of the foundation of the house being built

Flood zones have varying levels of risks to avoid. You can reduce damage to your property if you select a suitable foundation to withstand flooding. The FEMA has standards set for special hazard locations that include A and V zones. The foundation types you can use for these zones include:

  • For A and coastal V zones - Continuous pile (fill or stem wall) foundations, without or minimal obstruction
  • For A zones (except for coastal A) - The following are the foundation types for this zone:
    • Slab on compacted fill
    • Slab cap on a filled stem wall
    • Unfinished and floodable crawlspace
    • Pile, post, column, or pier

Check your state codes or the FEMA technical bulletin 10-01 if they require a different foundation for your area.

How High Do I have To Build Above The Base Flood Elevation?

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For residential areas, your basement should be above the Base Flood Elevation. The BFE is the elevation of 1% chance that surface water rises due to flooding. It also refers to the statistical expectation of water level rise within 100 years in a certain location.

If your residence is in a special hazard flood area, the top of the basement floor should not be less than 5 feet below the BFE.

If your house is in the A zone (except coastal), you can add fillings to elevate the home above the BFE. For V zones, the lowest horizontal element should be above the BFE. Structures below the BFE are obstructive to flooding. As a result, flood insurance premiums will increase.

How Do You Waterproof A Basement In A Flood Zone?

If you live in areas with moderate to high flooding risks, waterproofing can help reduce the damage. But before anything else, you have to assess your basement. You have to inspect the following:

  • Clogging in downspouts, eaves, and gutters
  • Cracks, gaps, and damage to the foundation
  • Elevation of any landscaping outside your home
  • Flood zone area of the house

You can also ask a professional to check the condition of your basement. After the assessments, it is best to waterproof your basement against flooding.

Waterproofing A Flood-Prone Basement

Here are ways to floodproof your basement.

  1. Fix the causes of leaking in the basement. Seal the cracks and holes on the foundation or windows where water can pass through.
  2. Install backwater valves that prevent contaminated sewage water from coming inside the basement. The position of the valve should not allow flow to sinks and toilets.
  3. Prevent the floodwaters from seeping inside the basement foundations by using downspout extensions.
  4. You can also use splash bricks to prevent soaking of the ground.
  5. Unclog and clean your gutters.
  6. Raise the connections (e.g., electrical and HVAC systems) above the flood line. You can use some platforms or other similar means.
  7. Use waterproof flooring.
  8. If you have basement doors and windows, you can change them with flood-resistant options. If it's not feasible, you can use floorboards as a protective covering.

Aside from these measures, it would also help if you get flood insurance for your home. Some insurance companies may lower the insurance premiums if you have floodproofed your home. Also, check if the stipulations fit your flood protection needs.

Is A Flooded Basement Covered By Homeowners Insurance?

If you have bought home insurance, there are some provisions about flooding coverage. There are various causes of flooding. It can be natural due to calamities or man-made. Read below what will be covered or not by your home insurance.

Covered Not Covered
Caused by broken appliances
(washing machine, air conditioner,
or refrigerator)
Storm, water surge, heavy rainfall
Leaking from water heater External sewage backup (can have a limit or none)
Freezing pipes have burst (from AC units,
sprinklers, etc.)
Water seepage from underground
(directly related to flooding in the area)
Overflowing tub, sinks, or other water receptacles

It is best to get flood insurance for damages not covered by your home insurance. The stipulations may not cover all the costs, but at least you can reduce some expenses.

In Closing

Photo of a modern house with basement in a flood zone area, Can You Have A Basement In A Flood Zone?

You can have a basement even though you are in a flood-prone area. You must first identify the flood zone category of your home. There is a need to get flood insurance and meet the minimum height above the base flood elevation. By doing so, you will know the courses of action you need to take.

It is also necessary to choose the right foundations and waterproofing measures to prevent the damage caused by flooding. Also, take note that home insurance will not cover all cases of flooding. With thorough planning and preparation, you won't worry much about flooding in your basement.

Before you go, you might want to check out this post: Can You Fix A Leaky Basement From The Inside?

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