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The Complete Guide to Crawl Space Vent Cover Installation

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If your home includes a crawl space, it’s critical to keep it dry and mold-free. That is why HydroHelp911 provides expert crawl space vent cover installation services. Keeping your house warm during the winter and cool in summer can help you save money on energy bills. HydroHelp911 will also check for water damage and mold growth to ensure your family is safe from hazardous spores.

It’s crucial to understand that having a well-aired crawl area has numerous advantages. First, it can aid in reducing moisture, which is particularly important if you live in a location with high humidity or frequent rain. In addition to safeguarding your property from water damage, good ventilation reduces dust and allergies, making the air within your home cleaner. Everyone’s living situation will improve as a result of this!

With HydroHelp911’s professional services, you won’t have to worry about any harmful situations! Call right now to make an appointment!

How does crawl space ventilation work?

The space between the bottom of the livable space in your home and the ground is known as a crawl space if all or part of the structure is elevated slightly above the ground but not over the minimum height required for a basement.

Crawl space foundations are prevalent in humid, warm climates where it is preferable to raise the structure slightly above ground level to avoid moisture. When a section of the house, such as a porch, is detached from the main building and has its foundation, crawl spaces are occasionally found in conjunction with basement foundations.

Moisture is the single most harmful ingredient in dwellings. Moisture is to blame for many issues in a home, including wood rot and numerous mold and mildew stains. Moisture alone, if left unchecked, can quickly bring the quality of your home down.

The best weapons against crawl space dampness are natural light, heat, and ventilation. Because it’s challenging to provide light and warmth to a crawl area, the best approach stimulates adequate airflow.

Building rules have traditionally mandated that crawl spaces be adequately vented to help keep these spaces dry and avoid damage from moisture that might corrode beams, joists, and flooring. A set of rectangular screened vents installed into the concrete block foundations enclosing the crawl space generally provide this airflow.

How to inspect and correct a vented crawl space for vent covers?

In the United States, crawl spaces are usually made of hollow masonry blocks or poured concrete stem walls. In general, permanent vents to the outside are installed in these foundations to provide cross-ventilation and prevent moisture from entering the interior.

Up until recently, houses built atop vented crawl spaces have been designed with little or no attention to moisture-causing sources that can lead to long-term structural damage and cause health issues. As a result, numerous construction components interior and exterior details must be examined and installed correctly to counteract undesired moisture in a crawl space.

According to previous studies, a traditionally vented crawl space converted to an unvented and conditioned space performs similarly to houses with basements, with various advantages for the homeowner, including:

  • Energy savings
  • Increased comfort
  • Moisture control
  • Long-term durability
  • Healthier air quality

Crawl Space Vent Services

According to studies, vented crawl spaces in mixed or warm environments tend to raise the moisture level within the area rather than keep it drier. This extra moisture condenses on the floor framing’s cooler wood surfaces, encouraging fungus growth and wood deterioration.

If the necessary insulation technique is not correctly followed, vented crawl spaces have the potential to siphon energy savings from the home’s living rooms. Therefore, more than just sealing off the vent openings are required to convert a vented crawlspace into an unvented, insulated, sealed, and dry compartment. It is vital to take guidance from professional services like HydroHelp911 for Crawl Space Vent Cover Installation.

If naturally ventilated combustion equipment is installed in the crawlspace, not considering other details and just shutting the vents could worsen the situation, increasing moisture levels and potentially creating a fatal situation. Depending on the requirements, it may be advisable to gradually deploy the closed-crawl space technique to avoid the impacts of materials drying up too quickly.

Quick and excessive drying can cause superficial damage to wood-based finish products in the home’s living area. Swollen and cupped hardwood flooring, on the other hand, may flatten throughout the drying process. Watch the Best Way To Seal Foundation Vents

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International Residential Code (IRC) Requirements

The International Residential Code (IRC) elaborates all code standards for all stages of home development virtually. The IRC’s criteria constitute the foundation for all code requirements for the residential property unless local and state rules supersede them.


Section R408, in multiple paragraphs, contains the IRC prescriptions for venting crawl spaces. The typical criterion for crawl space ventilation is stated in the first paragraph of IRC section 408-

Ventilation vents shall be provided through foundation walls or exterior walls in the under-floor area between the bottom of the floorboards and the earth under any building (excluding space occupied by a basement). Except for the ground, the surface is covered by Class 1 vapor limiter material; the minimum net area of ventilation apertures shall be 1 square foot for every 150 square feet of under-floor space area.

When utilizing a Class 1 vapor retardant material, the minimum net area of ventilation holes for every 1,500 square feet of under-floor space area must be at least 1 square foot. In addition, each corner of the building must have a ventilation opening within 3 feet.


Every vent must be a minimum of 1 square foot in size and may be made of any of the following materials:

  • Plates of expanded sheet metal with a thickness of at least 0.047 inches
  • Perforated sheet metal plates with a thickness of at least 0.070 inch
  • Cast-iron grill
  • Vents made of extruded load-bearing bricks
  • 0.035-inch wire or stronger hardware cloth
  • Corrosion-resistant wire mesh with a minimum thickness of 1/8-inch
  • The vents can be of the adjustable louver type if you’re installing a ground vapor barrier


This paragraph provides cases where builders and homeowners opt not to install vents in crawl spaces, primarily to reduce thermal heat loss or prevent insects and other vermin from entering the crawl area.

Builders can now create non-vented crawl areas if they follow the following procedures:

  • Mechanically circulating air should be provided between the upper conditioned portion of the home and the crawl space.
  • Somewhere in 150 square feet of crawl space, the air-circulating system must move at least one cubic foot of air.
  • A vapor-retardant material must be used to seal the crawl space floor area thoroughly.
  • The vapor retarder’s edges should be placed up against the inner foundation walls. Separate sheets that are overlapped must be done so by at least 6 inches. It is necessary to caulk the seams.
  • All crawl area walls must be insulated with R-values that are suitable for the weather patterns.

For many years, HydroHelp911 has assisted property owners in North Carolina with foundation repair and moisture problems. Advanced Ventilation Solutions began as a crawl space repair and basement waterproofing business that grew swiftly, but we performed minimal ventilation services. As a result, our company re-evaluated its name to reflect our essential services and future goals better, and HydroHelp911 was created, ready to serve the inhabitants of lovely North Carolina.

Contact HydroHelp911 today.

We will do everything we can to ensure your experience with us will be invaluable. Give us a call at 704-753-8756 to schedule a free inspection.



In the summer, working vents in the crawl space are usually required by building codes to pass outside air to circulate under the floor and avoid moisture buildup – discouraging mildew, mold, and wood deterioration, among other things.


It’s only a matter of time before mold, mildew, and other bacteria start growing in your crawl space if you don’t ventilate or actively vent it. Keeping up with your home’s hygiene by airing it out with open windows and doors is critical to keeping it fresh and crisp.


The pros of having vented crawl space are – 1)Summer temperatures are more relaxed. In addition, it’s easy to keep the crawl space at a low humidity level. 2) Insulation materials and vapor barriers are not exposed to the outside atmosphere.


According to the IRC, every 150 square feet of crawl area should have one square foot of screened vent. In addition, residents can further avoid moisture by covering the uncovered ground with a vapor-barrier material that the city has approved.


All crawl spaces should be well-sealed and kept dry from both the air and the earth.

Contact HydroHelp911 Today!

HydroHelp911 will do everything we can to ensure your experience with us is excellent.

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