Ventilating your crawl space has been proven not. At the very least you need to keep your vents to your crawl space closed in the heat of summer and winter as well but thats another article.
Now most people close their crawl space vents in the wintertime to keep the cold out so that the cold air doesnt freeze the pipes under the house.
When should you close your crawl space vents. However in both cases you still have to fulfill or meet certain conditions. The opportunities for air exchange between June and September are less frequent and far between. Closing crawl space vents to block the movement of outside air into the crawl space will only provide a small degree of protection from the cold.
During hot weather the vents would be left open to allow outside air to circulate in the crawl space which would theoretically cool the rest of the house. Trying to guess when to open and close your vents during this time period becomes impossible for any homeowner. Your crawl space vents should always be closed and sealed off from the outside elements.
But theres a newer approach that says the vents should be sealed shut at all times. First and foremost open vents allow moisture to enter your crawl space. Think of your crawl space as a short basement.
The traditional line of thinking is the vents should be open in the summer and closed in the winter. In winter when the air is drier the vents are closed to reduce the chance that the pipes in the crawl space might freeze. It should be insulated around the perimeter on the inside of the crawl space walls which makes this a heated space in the winter.
When is the humidity lowest outside. Many homes with a crawl space will have heating ducts in this area and these ducts perform best when they are in a warm space in the winter. Ventilating Your Crawl Space OR Sealing Your Crawl Space.
In most cases like in our area in East Tennessee its in the winter. During the summer it is a completely different phenomenon. So our answer is to open and close the vents in your crawlspace seasonally instead of deciding to seal off crawl space vents altogether.
How to Close Foundation Vents in the Winter. However the right answer is very clear. Otherwise keep them open when the temperature is consistently above freezing to avoid moisture-related problems.
Those crawl spaces generally have the worst insect and rot damage. Venting your crawl space leads to a variety of issues. So the idea of venting a crawl space was born.
Open vents when over 70 deg F. But which approach is right for your home. So our answer is to open and close the vents in your crawlspace seasonally instead of deciding to seal off crawl space vents altogether.
A good rule of thumb is to close your crawl space vents once the outside temperature starts dipping down below 40 degrees F. The crawl space itself is outdoor space complete with insects and rodents who squeeze in through imperfectly screened vent openings. In short you should do everything in your power to keep the cold air out.
But they also say you could close them. In the winter when the air is drier the vents are closed to reduce the chance that the pipes in the crawlspace might freeze. Crawl space vents need to be.
For best results place two vents each on opposing walls. Close crawl space vents to protect the pipes and wood under your house. We strongly recommend you close the vents as theres no way to control humidity when the crawl space is open.
In the winter when the air is drier and there is less humidity the vents could be closed so that the water and sewage pipes wouldnt freeze. The safest and most commonly accepted code for any home is to leave crawlspace vents in place year round. Why take this measure.
If you must close your vents during winter I highly encourage you to do it only when the temperature drops below 32⁰. So the buildings thermal boundary is the floor assembly. Open and close crawlspace vents seasonally In the winter when the air is drier the vents are closed to reduce the chance that the pipes in the crawlspace might freeze.
If you close the vents in your crawl space youre actually keeping the dry air out. Spring and fall would be the most ideal times to have your vents open. Close vents when under 40 deg F.
There is a better answer – sealing your entire crawl space against Mother Natures wrath. A ground cover should be used in conjunction with ventilation. So if your crawl space is musty dirty and contaminated with mold so is your home.
When it comes to crawl space vents open or closed the big debate doesnt want to go away. However there are a few things you can do to help combat those cold winter floors and reduced heating inefficiency due to drafts. An even better solution is to cut foam board the exact size of the vent and press it into place to block all air from penetrating.
One of the major debates in the world of crawl spaces these days is how to make use of the vents. However this doesnt mean that closing the vents is the solution to all of your winter crawl space concerns. Thermostatically controlled automatic louvers and manually operated louvers are available that can close off the vents when the temperature drops below freezing.
Compared with the leakiest worst case scenario however closing up a crawlspace can make quite a difference. 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 science behind crawlspaces.
The HUD standard typical of others recommended four crawl space vents with a total minimum free vent equal to 1150 of the crawl space floor area if there is a ground cover 11500 with the ground uncovered. So theyre giving the homeowner or builders a choice whether to create an encapsulated system or an open system.