Questions & Answers

For decades, the national response to flood disasters was generally limited to constructing flood-control works such as dams, levees, sea-walls, and the like, and providing disaster relief to flood victims. This approach did not reduce losses, nor did it discourage unwise development. In some instances, it may have actually encouraged additional development. To compound the problem, the public generally could not buy flood coverage from insurance companies, and building techniques to reduce flood damage were often overlooked.In the face of mounting flood losses and escalating costs of disaster relief to the general taxpayers, the U.S. Congress created the NFIP. The intent was to reduce future flood damage through community floodplain management ordinances, and provide protection for property owners against potential losses through an insurance mechanism that requires a premium to be paid for the protection.

We built our flood vents out of a durable ABS plastic so they do not rust or rot and they do not have to be maintained. Metal flood vents need to be oiled and sprayed with a lubricant to keep them from rusting.

12 Mil is a stronger plastic and will last longer. The difference in color you see from various 12 mil vapor barriers on the market only differs by who manufactures it and has no practical application. When installing 12 Mil, you should always lay the side with color on the ground and leave the white side facing up.

The National Flood Insurance Act of 1968 (PDF 446KB) allows FEMA to make flood insurance available only in those areas where the appropriate public body has adopted adequate floodplain management regulations for its flood-prone areas. Individual citizens cannot regulate building or establish construction priorities for communities. Without community oversight of building activities in the floodplain, the best efforts of some to reduce future flood losses could be undermined or nullified by the careless building of others. Unless the community as a whole is practicing adequate flood hazard mitigation, the potential for loss will not be reduced sufficiently to affect disaster relief costs. Insurance rates also would reflect the probable higher losses that would result without local floodplain management enforcement activities.

We designed it to attach to the outside surface of the foundation wall for two main reasons; to make it easy to install with either construction adhesive or stainless screws and so you do not have to chisel or grind the brick

Without cross-ventilation, air in unventilated corners or areas of a crawlspace becomes stagnant and foul. Portable crawlspace fans correct this problem by directing air flow into unventilated crawl space areas.

The presence of moisture is what leads to mold, which can be bad for your health and costly to remove. According to the Environmental Protection Agency, the way to control mold is to control moisture. The main source of crawl space moisture is ground evaporation, and ventilation allows this evaporation to dissipate. Proper ventilation exhausts moisture from the crawlspace and replaces it with fresh, drier air—providing effective moisture control. Ventilation also helps to remove strong odors and dangerous radon gas from the crawlspace. For further reading take a look at our Why Ventilate the Crawlspace page.

The presence of moisture is what leads to mold, which can be bad for your health and costly to remove. According to the Environmental Protection Agency, the way to control mold is to control moisture. The main source of crawl space moisture is ground evaporation, and ventilation allows this evaporation to dissipate. Proper ventilation not only exhausts moisture from the crawlspace but replaces it with fresh, drier air providing effective moisture control. Ventilation also helps to remove strong odors and dangerous radon gas from the crawlspace.

The presence of moisture is what leads to mold, which can be bad for your health and costly to remove. According to the Environmental Protection Agency, the way to control mold is to control moisture. The main source of crawl space moisture is ground evaporation, and ventilation allows this evaporation to dissipate. Proper ventilation not only exhausts moisture from the crawlspace but replaces it with fresh, drier air providing effective moisture control. Ventilation also helps to remove strong odors and dangerous radon gas from the crawlspace.

We did not want any moving parts that could malfunction and stop the flow of water during a flood situation. We also wanted them to stay in the open position to allow fresh air to flow into and out of the crawlspace.

The portable fan can continued to be used to move "dead air" in the crawlspace.

The 8”x16” manual air vent can still be used to ventilate the crawlspace, providing 95 NFA-double most air vents on the market.

A community can be placed on probation 90 days after FEMA provides written notice to community officials of specific deficiencies. Probation generally is imposed only after FEMA has consulted with the community and has not been able to resolve deficiencies. The FEMA Regional Director has the authority to place communities on probation.

INSIDE HUMIDISTAT (Model HUC) - This device monitors humidity inside the crawlspace and turns the fan on when the humidity rises above a preset limit. This humidistat is placed in a crawlspace problem area and usually set at 50% humidity. Mold will not grow when the humidity is under 50%.RAIN HUMIDISTAT (Model HUD) - This damp weather shut-off device monitors humidity of incoming air and turns the fan off when the outside air is damp, such as during a heavy rainfall. This humidistat is placed inside the crawlspace near an intake air vent and usually set at 80% humidity.THERMOSTAT (Model TH) - The thermostat turns the fan off when the inside temperature drops below a certain preset temperature. The preset temperature is usually set around 40 deg F to prevent frozen pipes.

WEATHER STATION (Model WS) - This component monitors the temperature and humidity in the crawlspace. The crawlspace sensor is wireless. The monitor is portable (and can be located in a convenient location in the house), with an easy-to-read LED screen.

Participation in the CRS is voluntary. A community in compliance with the rules and regulations of the NFIP may apply. The community's Chief Executive Officer must appoint a CRS coordinator to handle the application work and serve as the liaison between the community and FEMA. The first step in the application process is for the community to obtain a copy of the CRS Coordinator's Manual which describes the program and gives details on the eligible activities. The CRS coordinator should fill out and submit an application for participation in the CRS. The CRS will verify the information and arrange for flood insurance premium discounts.

An additional $50 charge is added to the premium for each policy sold or renewed in the community. The additional charge is effective for at least 1 year after the community's probation period begins. The surcharge is intended to focus the attention of policyholders on the community's non-compliance to help avoid suspension of the community, which has serious adverse impacts on those policyholders. Probation does not affect the availability of flood insurance.

The Write Your Own (WYO) Program, begun in 1983, is a cooperative undertaking of the insurance industry and FEMA. The WYO Program allows participating property and casualty insurance companies to write and service the Standard Flood Insurance Policy in their own names. The companies receive an expense allowance for policies written and claims processed while the Federal Government retains responsibility for underwriting losses. The WYO Program operates within the context of the NFIP, and is subject to its rules and regulations.The goals of the WYO Program are: Increase the NFIP policy base and the geographic distribution of policies; Improve service to NFIP policyholders through the infusion of insurance industry knowledge; and Provide the insurance industry with direct operating experience with flood insurance.Currently, about 100 insurance companies write flood insurance with FEMA.

A community participating in the Regular Program of the NFIP is usually provided with a Flood Insurance Rate Map (FIRM) and a detailed engineering study, termed a Flood Insurance Study (FIS). (Additional information on FIRMs and FISs is provided in the "Flood Hazard Assessment and Mapping Requirements" section of this booklet.) Under the Regular Program, more comprehensive floodplain management requirements are imposed on the community in exchange for higher amounts of flood insurance coverage.

The NFIP Regulations for enclosures are codified in the Title 44 of the Code of Federal Regulations, in Section 60.3(c) (5), which states that a community shall: "Require, for all new construction and substantial improvements, that fully enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access or storage in an area other than a basement and which are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria: A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided. The bottom of all openings shall be no higher than one foot above grade. Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters."

The NFIP is a Federal program enabling property owners in participating communities to purchase insurance protection against losses from flooding. This insurance is designed to provide an insurance alternative to disaster assistance to meet the escalating costs of repairing damage to buildings and their contents caused by floods.Participation in the NFIP is based on an agreement between local communities and the Federal Government that states if a community will adopt and enforce a floodplain management ordinance to reduce future flood risks to new construction in Special Flood Hazard Areas, the Federal Government will make flood insurance available within the community as a financial protection against flood losses.

The portable fan is connected to a 10 flex duct and the other end of the flex duct to an 8x16 foundation air vent. Evacuating air from the crawlspace removes radon, odors and moisture from under the house.

A community, as defined for the NFIP's purposes, is any State, area, or political subdivision; any Indian tribe, authorized tribal organization, or Alaska native village, or authorized native organization that has the authority to adopt and enforce floodplain management ordinances for the area under its jurisdiction. In most cases, a community is an incorporated city, town, township, borough, or village, or an unincorporated area of a county or parish. However, some States have statutory authorities that vary from this description.

A fan control system has various components, including humidistats (instruments for measuring and controlling humidity) and a thermostat. The fan control system turns the fan on and off. The fans can be controlled to come on when the crawlspace humidity reaches a certain preset amount. Similarly, they can be set to not come on if humidity is higher outside the crawlspace than inside the crawlspace, or when the temperature in the crawlspace is cold enough to freeze pipes. See our fan control products.

A fan control system has various components, including humidistats (instruments for measuring and controlling humidity) and a thermostat. The fan control system turns the fan or fans on and off. The fans can be controlled to come on when the crawlspace humidity reaches a certain preset amount. Similarly, they can be set to not come on if the humidity is higher outside the crawlspace than in the crawlspace, or when the temperature in the crawlspace is cold enough to freeze pipes.

A crawlspace door fan removes radon, odor and moisture from the crawlspace and pull in fresh air from the outside environment. The shutter fan is mounted in the crawlspace door for easy installation without hindering access to the crawlspace.

TB 1 / August 2008 is a FEMA technical bulletin titled Openings in Foundation Walls and Walls of Enclosures – Below Elevated Buildings in Special Flood Hazard Areas in accordance with the NFIP. This technical bulletin explains NFIP’s foundation flood opening requirements. It also explains the NFIP’s requirements for guidance on non-engineered openings and engineered openings. This technical bulletin is attached.

Suspension of a participating community (usually after a period of probation) occurs when the community fails to solve its compliance problems or fails to adopt an adequate ordinance. The community is provided written notice of the impending suspension and granted 30 days in which to show cause why it should not be suspended. Suspension is imposed by FEMA. If suspended, the community becomes non-participating and flood insurance policies cannot be written or renewed. Policies in force at the time of suspension continue in force for the policy term.

Probation is the formal notification by FEMA to a community that its floodplain management program does not meet NFIP criteria. It is an action authorized under Federal regulations.

NFIP is the National Federal Insurance Program. The NFIP is a Federal program enabling property owners in participating communities to purchase insurance protection against losses from flooding. This insurance is designed to provide an insurance alternative to disaster assistance to meet the escalating costs of repairing damage to buildings and their contents caused by floods.

ICC stands for International Code Counsel. ES stands for Evaluation Service. ICC-ES evaluates building products for compliance with code. For more information about ICC visit their website at www.icc-es.org. Crawl Space Door Systems, Inc. is a member of ICC.

This is an ICC test that is used to prove that an automatic flood vent opens during a flood event. The title of ICC-ES (AC364) is "Acceptance Criteria for Automatic Foundation Flood Vents". Some flood vents have an automatic lid that is closed when there is not a flood event and opens automatically when there is a flood vent.

FEMA is the Federal Emergency Management Agency. FEMA’s mission is to support citizens and first responders to ensure that as a nation we work together to build, sustain, and improve a capability to prepare for, protect against, respond to, recover from, and mitigate all hazards.

CFM means Cubic Feet per Minute. CFM helps determine what size fan will suit your crawlspace ventilation needs. When purchasing a fan you want to know how much air the fan will move. Air movement is measured in CFM. To calculate the volume of air in the crawlspace you multiple the height x width x length of the crawlspace. For example, if your crawlspace is 40’ long, 20’ wide and 3’ high the vol ume on air in the crawlspace is 2,400 (40x20x3) cubic feet. If you want to replace all of the air in this crawlspace every 4 minutes you need a 600 (2,400/600) CFM fan.

Engineer openings have a characteristic that differ from non-engineered openings. They are designed and certified by a registered design professional as meeting certain performance characteristics described in FEMA TB 1 / August 2008. Engineered openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters. The advantage of an engineered flood vent compared to a non-engineered vent is it takes fewer engineered flood vents to meet NFIP’s requirements.

In support of the NFIP, FEMA identifies flood hazard areas throughout the U.S. and it's territories by producing Flood Hazard Boundary Maps (FHBMs), Flood Insurance Rate Maps (FIRMs), and Flood Boundary & Floodway Maps (FBFMs). Several areas of flood hazards are commonly identified on these maps. One of these areas is the Special Flood Hazard Area (SFHA) or high risk area defined as any land that would be inundated by a flood having a 1-percent chance of occurring in any given year (also referred to as the base flood).The high-risk area standard constitutes a reasonable compromise between the need for building restrictions to minimize potential loss of life and property and the economic benefits to be derived from floodplain development. Development may take place within the SFHA, provided that development complies with local floodplain management ordinances, which must meet the minimum Federal requirements. Flood insurance is required for insurable structures within high-risk areas to protect Federal financial investments and assistance used for acquisition and/or construction purposes within communities participating in the NFIP.

The Portable Exhaust Fan System converts our Portable Fan to an Exhaust Fan to help pull unwanted moisture out of the crawlspace. The Portable fan is connected to a 10” - 2ply - double walled -flex duct and to a 8"x16" foundation air vent to newly designed duct connectors. Evacuating air from the crawlspace removing radon, odors and moisture from under the house.

A non-engineered opening is calculated by multiplying the height times the width of the flood vent’s opening. They are used to meet the NFIP’s prescriptive requirements of 1 square inch of net open area for every square foot of enclosed area.

"Flood" is defined in the Standard Flood Insurance Policy (SFIP), in part, as:A general and temporary condition of partial or complete inundation of two or more acres of normally dry land area or of two or more properties (at least one of which is your property) from overflow of inland or tidal waters, from unusual and rapid accumulation or runoff of surface waters from any source, or from mudflow.

A vapor barrier is also known as “poly” or "moisture barriers." Most building codes now require vapor barrier in the crawlspace. 40% of moisture comes from the ground, therefore, the plastic is putting a barrier between the moisture that comes from the earth and the sub floor of your home. Poly is intended to retard the migration of moisture in your crawlspace.

Communities are required to adopt and enforce a floodplain management ordinance that meets minimum NFIP requirements. Communities that do not enforce these ordinances can be placed on probation or suspended from the program. This is done only after FEMA has provided assistance to the community to help it become compliant.

Flood insurance under the NFIP is not available within that community. Furthermore, Section 202(a) of Public Law 93-234, as amended, prohibits Federal officers or agencies from approving any form of financial assistance for acquisition or construction purposes in a Special Flood Hazard Area (SFHA). For example, this would prohibit loans guaranteed by the Department of Veterans Affairs, insured by the Federal Housing Administration, or secured by the Rural Housing Services. Under Section 202(b) of Public Law 93-234, if a Presidentially declared disaster occurs as a result of flooding in a non-participating community, no Federal financial assistance can be provided for the permanent repair or reconstruction of insurable buildings in SFHAs. Eligible applicants may receive those forms of disaster assistance that are not related to permanent repair and reconstruction of buildings.If the community applies and is accepted into the NFIP within 6 months of a Presidential disaster declaration, these limitations on Federal disaster assistance are lifted.

Any vapor retarder that is not reinforced refers to the thickness of the plastic. Anything that is reinforced beyond 12 mil refers to the thickness of the fiber. The vapor barrier is reinforced to make it stronger so that it won't rip while you are moving around in your crawlspace.

Crawl Space Door Systems offers three types of fans. All meet OSHA standards and have OSHA-approved components, including an OHSA-approved grill around the fan blades. All have a corrosion-resistant frame and aluminum shutter. PORTABLE FANS - These are used to direct air into hard-to-reach areas of the crawlspace to create an air jet stream and cross flow ventilation. Used for cross-ventilation, they increase the cross-flow of air. SHUTTER FANS - Shutter fans are used to evacuate radon, odors and moisture from the crawlspace and pull in fresh air from the outside environment. The shutter fan is designed to be mounted in the crawlspace's foundation wall. The shutters open when the fan turns on and blows the shutters open. The shutters drop closed when the fan is turned off. DOOR-MOUNTED SHUTTER FAN - This fan is used to evacuate radon, odors and moisture from the crawlspace and pull in fresh air from the outside environment. The shutter fan is mounted in the crawlspace door for easy installation without hindering access to the crawlspace.

You can save money on your flood insurance premiums by reducing your homes' flood risk.   Flood risk is unique to each structure and depends upon factors such as the elevation of the property relative to predicted flood levels, the construction style of the building, and the flood risk zone.   Adding flood vents to your homes' foundation walls provides a means that permit the automatic entry and exit of floodwaters which protects your foundation and reduces your flood risk. Lowering your flood risk reduces your flood insurance premiums according to the National Flood Insurance Program.

Engineered flood vents differ from non-engineered flood vents in that they are designed and certified by a registered design professional. Engineered openings may be equipped with screens, louvers, valves, or other coverings provided that they permit the automatic entry and exit of floodwaters.

Poly Stakes: less work to keep the poly down versus using common insulation stakes/tiger teeth.

Use butyl tape and Christmas tree fasteners if you are encapsulating and bringing the vapor retarder up the wall or pillars.

Use Capped Vapor Barrier Stakes for a finished look and easier installation of the stakes. The Buttons are great for helping pound the stakes with a rubber mallet.

Community participation in the NFIP is voluntary (although some States require NFIP participation as part of their floodplain management program). Each identified flood-prone community must assess its flood hazard and determine whether flood insurance and floodplain management would benefit the community's residents and economy. However, a community that chooses not to participate within 1 year after the flood hazard has been identified and an NFIP map has been provided is subject to the ramifications explained in the answer to Question 20.A community's participation status can significantly affect current and future owners of property located in Special Flood Hazard Areas (SFHAs). The decision should be made with full awareness of the consequence of each action.

The U.S. Congress established the NFIP on August 1, 1968, with the passage of the National Flood Insurance Act of 1968. The NFIP was broadened and modified with the passage of the Flood Disaster Protection Act of 1973 (PDF 446KB) and other legislative measures. It was further modified by the National Flood Insurance Reform Act of 1994 (PDF 294KB) and the Flood Insurance Reform Act of 2004. The NFIP is administered by Federal Emergency Management Agency (FEMA) a component of the Department of Homeland Security (DHS).

Probation may be continued for up to 1 year after the community corrects all Program deficiencies and remedies all violations to the maximum extent possible.

Through the NFIP, property owners in participating communities are able to insure against flood losses. By employing wise floodplain management, a participating community can protect its citizens against much of the devastating financial loss resulting from flood disasters. Careful local management of development in the floodplains results in construction practices that can reduce flood losses and the high costs associated with flood disasters to all levels of government.

The crawlspace fans and fan systems are relatively inexpensive to purchase and operate, easy to install and very durable.

The crawlspace fans and fan systems are not only relatively inexpensive to purchase and operate, they're also easy to install and very durable. Crawlspace moisture control is a large problem. A contractor or termite company can offer profitable services by using these products

Exhaust fans pull air out of the crawl space and removes radon, odors and moisture. Moisture causes mold, and mold is both costly to remove and dangerous to people, especially young children and individuals with breathing problems. Exhausting crawl space air removes the bad air and brings in fresh air from the outside environment. Bad or stagnant air in the crawlspace seeps into the home through cracks in the floor, which can cause health problems in asthmatics and children.

While various manufacturers' products have certain similarities and differences, sometimes you may feel like you're comparing apples and oranges. The best indicator to follow is to check the fan system which offers the CFMs (cubic feet per minute) of air displacement that you need and when you want the fans to turn on and off.

NFIP's main flood insurance requirements are:

1. You must have at least one square inch of opening in the foundation wall for every square foot of house’s enclosed area.
2. The bottom of the flood vent opening must be less than 12 inches above the ground.
3. Two vents per enclosed area, on different exterior walls.

The CRS Coordinator's Manual, additional CRS publications, and software may be ordered online or by writing, phoning, or faxing a request to the NFIP/CRS. Contact information is listed in the "Additional Reading" section at the end of the booklet. All publications are free, and the computer software for completing the application is also available at no charge.

The NFIP's Community Rating System (CRS) recognizes community efforts beyond the NFIP minimum standards by reducing flood insurance premiums for the community's property owners. The discounts may range from 5 to 45 percent. The discounts provide an incentive for new flood mitigation, planning, and preparedness activities that can help save lives and protect property in the event of a flood.

No. federal policy does not allow FEMA to approve, endorse, certify or recommend any products. While a product may be in compliance with FEMA design guidance, any language from manufacturers stating their product is "FEMA approved" or "FEMA certified" is incorrect.  Non-engineered flood vents do not need a certification. Engineered flood vents require certifications for the state they will be installed.  Companies  claiming that their flood vent is the only "legal" flood vent is also incorrect.  Our Engineered Flood Vents offer competitive coverage area, for an affordable price, compared to other engineered flood vents on the market.

No. TB 1 / August 2008 defines the 3" opening size on page 26 as: "Engineered openings are to be not less than 3 inches in any direction in the plane of the wall. This requirement applies to the hole in the wall, excluding any screen, grate, grille, louvers or devices that may be placed in or over the opening." Title 44 of the Code of Federal Regulations, in Section 60.3(c) (5), states: "Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters." The 3 inch rule is for the hole in the wall not the space between the louvers or screens.

As established by the U.S. Congress, the sale of flood insurance under the NFIP is subject to the rules and regulations of FEMA. FEMA Division has elected to have State-licensed insurance companies' agents and brokers sell flood insurance to consumers. State regulators hold the insurance companies' agents and brokers accountable for providing NFIP customers with the same standards and level of service that the States require of them in selling their other lines of insurance.Private insurance companies participating in the Write Your Own (WYO) Program must be licensed and regulated by States to engage in the business of property insurance in those States in which they wish to sell flood insurance.

Not if the flood vent package is labeled with the opening size. TB 1 / August 2008, page 20 sates: "Manufacturers of devices intended for use as standard air vents typically indicate the number of square inches that each device provides for air flow (either stamped into the metal frame or noted on the packaging).

Yes. NFIP's flood insurance requirements boil down to this: You must have at least one square inch of opening in the foundation wall for every square foot of house’s enclosed area. The bottom of the flood vent opening must be less than 12 inches above the ground. Two vents per enclosed area, on different exterior walls.

Yes. Title 44 of the Code of Federal Regulations, in Section 60.3(c) (5), states: "Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters."

No. TB 1 / August 2008 explains on page 19 that it is unacceptable to "have detachable solid covers that are intended to be manually installed over the opening in cold weather, because they do not allow for the automatic entry and exist of floodwaters when the cover is in place."

No. ICC-ES (AC364) is a test to prove an automatic flood vent opens automatically to allow flood waters to enter and exist. This is a requirement for flood vents that automatically open and closes. Our vents stay in an open position all of the time and do not require this test. The criteria for this test is attached and titled "ICC-ES (AC364)". Also, attached is an example of the evaluation report "ESR-2074" showing results of the test.