In winter, particularly in cold climates, closing crawl space vents can help prevent cold air from entering the space and potentially freezing pipes. The simplest way to close foundation vents for the winter is to plug them from the outside with foam blocks made specifically for this purpose.
The general rule is to keep vents open in the summer to circulate dry air and closed in the winter (below 40°F) to prevent frozen pipes and heat loss. Seasonal Adjustment: Opening vents during warm months reduces humidity and mold risk, while closing them during storms prevents rainwater intrusion.
Because your home's HVAC system is designed to regulate the temperature of the entire house, when ducts are closed, this pressure can build up and may eventually cause damage to your ducts or heating system. To sum it up, closing your air vents may mean that: Your HVAC system must work harder.
Rodents are attracted to crawl spaces because they are warm, damp, and protected from the elements. In addition, they are typically near food supplies (such as trash), and are not usually monitored frequently by homeowners.
Natural Smells the Amish Use to Repel Mice
Traditional methods often include using natural deterrents like peppermint, pine, or other strong plant-based smells. Whether it's growing plants near entry points or using oils indoors, these scents can interfere with how mice navigate and make the space less appealing.
This movement of mice and rats to find shelter indoors is known as rodent season. It can begin as early as August or as late as October depending on where you live and the weather conditions in a given year.
Due to inefficiencies in relying on existing attic vents for air intake, attic fans have lost popularity. These vents often aren't designed for this purpose, resulting in inadequate replacement air supply. The cons include regular maintenance, potential noise pollution, and associated costs.
The $5,000 rule is a guideline to help homeowners decide whether to repair or replace their HVAC system. You multiply the age of your unit by the cost of the needed repair. If that number exceeds $5,000, replacing your HVAC system is often more cost-effective.
Hot air rises.. so if you shut the lower vents in winter, the lower areas will stay cold, but if you open the lower vents the heat will rise to the top of the house anyway. If its cold in the basement open the vents in the basement. They may have been closed to push more heat to the upper floor.
If you live in colder climates, consider foam insulation board. It's an excellent material for creating vent covers that help maintain a stable temperature in the crawl space: lightweight, easy to cut, and provides reliable protection against cold air.
In uninsulated or poorly maintained crawl spaces, the lack of temperature control makes your pipes particularly vulnerable to freezing during cold snaps.
Vents that are not properly sealed or have loose covers can be an easy access route for mice. Once inside, they can move through your home using the vent system. They are attracted to warm spaces, and vents often provide just that. It's crucial to be aware of this possible access point and take action to secure it.
Surprisingly, we recommend not using foundation blocks to cover your vents. Keeping your foundation vents open, even during winter, helps maintain airflow under your home. Good ventilation is essential because it prevents moisture buildup, which can lead to mold growth, wood rot, and other structural issues.
Most crawl spaces are poorly insulated and sit right on top of cold, damp earth. Without proper crawl space heating and moisture control, they become the perfect storm: cold air seeps up into your living space, moisture leads to mold and wood rot, and your HVAC system works overtime to make up for the energy loss.
Sealing Vents
Once the crawl space is prepared, the next step is sealing off any openings. Vents and doors are typically sealed using airtight covers or insulation panels that fit securely over the openings.
In short, the 20-degree rule of air conditioning states that you should always keep your AC unit at no more than 20 degrees lower than the outside temperature. It means that, if the outdoor conditions are at 95 degrees, you should set your thermostat at no less than 75 degrees.
5 Warning Signs It's Time for Furnace Replacement
Have HVAC Prices Gone Up in 2026? Yes HVAC prices have steadily increased over the past few years, and 2026 is no exception. These increases are affecting everything from entry-level systems to high-efficiency units, making it more expensive than ever to install or replace HVAC systems.
This means you should divide the number of vents by two. We need 10 vents for our 2000 sq. ft. application if you are choosing a 50 square inch roof vent.
In 2026, lighting and ceiling fans step out of the background and into the spotlight, becoming essential design elements that define the entire space. The way a room is lit, how light moves throughout the day, and even how air circulates all play a role in how a home feels to live in, not just how it looks.
While it can remove warm air, attic fans don't introduce cool air, which means homeowners in warmer climates will still rely on air conditioning units. Energy Costs– While running an attic fan isn't more energy intensive than a whole house fan; you won't see substantial energy savings.
Mice are unlikely to climb on you when you sleep unless they are already in the bedroom. The best way to keep them out is by not giving them a reason to stay.
Ammonia. Ammonia is one of the stronger scents mice hate because it gives off a smell similar to predator urine, which can signal danger. Homeowners sometimes place small dishes of ammonia near entry points or in areas where mouse activity has been spotted.
You might think that spotting one mouse means you only have one mouse. This rarely happens. Mice live in family groups and reproduce quickly. If you see one mouse during the day, it usually means the hidden population has grown large enough that they're competing for food and space.