Now, we all know what basements are, and a concrete slab is just that \u2014 a slab of concrete. However, a common question homebuyers ask is: \u201cWhat is a crawl space?\u201d<\/p>\n
The short answer: A crawl space is an alternative to a traditional basement; it creates a barrier between the ground and the floor of your house.<\/p>\n A crawl space uses footings and walls (either made of cinder blocks or poured concrete<\/a>) to support the weight of the house. The walls can be up to 5 feet high<\/a>, but the typical crawl space is between 1 to 3 feet high, which means the homeowner will have to crawl to get around \u2014 hence the name.<\/p>\n Crawl spaces are also unfinished, making it easy to access the plumbing, gas hookups, ventilation, and wiring when needed.<\/p>\n Homeowners cannot count the crawl space as livable space like you potentially could with a basement<\/a>, but you can<\/i> use the crawl space to store smaller outdoor items. However, this wouldn\u2019t be in your best interest if your house is in a flood zone<\/a>. In a flood zone, the crawl space will act as a buffer between the water table and your floors because flood water will fill the crawl space before it floods the house. You also won\u2019t want to use the space as extra storage if you have problems with mold, moisture, or pests.<\/p>\n There are two types of crawl spaces: ventilated and conditioned.<\/p>\n Ventilated crawl spaces have several air vents located at the top of the foundation wall. The vents are situated across from one another so that outside air flows freely throughout the space. However, it\u2019s been recognized that vents can do more harm than good because the airflow is uncontrolled and unconditioned, meaning that the air (whether it is hot or cold) might be full of moisture.<\/p>\n It is possible to insulate a vented crawl space, but it\u2019s not easy. Typically, insulation is installed between floor joists, but trying to install insulation around plumbing, wiring, and other obstructions is challenging. As challenging as it may be, some new homes use this installation method.<\/p>\n Conditioned crawl spaces feature insulated walls and a tight vapor barrier on the floor that\u2019s connected to the HVAC system. This type of crawl space does not<\/i> have vents to the exterior, and it doesn\u2019t need insulation in between the floor joists.<\/p>\n It\u2019s important that a crawl space has a vapor barrier<\/a> covering the soil to reduce any additional moisture from the ground. Without this vapor barrier, crawl spaces can capture even more humidity. The vapor barrier also helps to keep the temperature stable year round, which helps to keep the heating and cooling system working efficiently.<\/p>\n We mentioned that crawl spaces need a vapor barrier, but what exactly is that? Randy Reeds<\/a>, a top-rated real estate agent from Kent County<\/a> in Michigan<\/a> who works with 72% more single-family homes than the average agent in his area, explains:<\/p>\n \u201cThere are fabrics contractors can put down to act as a vapor barrier in a crawl space that\u2019s not concrete. But, today they\u2019ll lay heavy plastic under the entire house to seal it \u2014 not too dissimilar to rubberized roofing material.\u201d<\/p><\/blockquote>\n If you have a crawl space with a dirt floor, you can use cross ventilation, a dehumidifier, or an exhaust fan to get rid of any excess moisture.<\/p>\n Keep in mind that the amount of moisture a dehumidifier can remove is dependent on how many quarts of water it can remove per hour. Also, there is moisture in ambient air, and it\u2019s important to keep air circulating<\/a> to and from the dehumidifier. This means you\u2019ll probably want to install several fans throughout the crawl space to increase airflow.<\/p>\n In the event of a heavy rainstorm, the crawl space may become flooded and the water will have to be pumped out, either by a professional, or you can have a sump pump<\/a> installed.<\/p>\n The biggest benefit to a crawl space over a concrete slab foundation is that you can more easily access the systems we mentioned above: the wiring, plumbing, gas hookups, and ventilation. If ever you have a problem with these parts of your home, you or a contractor can crawl into the crawl space under the house to make the necessary repairs.<\/p>\n Basements (finished or unfinished) grant homeowners access to the aforementioned systems and have more livable space (something that 44% of real estate agents<\/a> say their clients are looking for), and a crawl space does not.<\/p>\n However, the trade-off is that when you\u2019re building a house, a crawl space is going to save you a lot <\/i>of money \u2014 and most basements aren\u2019t included in a home\u2019s square footage, anyway. On average, a crawl space foundation is going to cost between $8,000 and $21,000<\/a>, whereas it would cost between $18,000 and $30,000<\/a> to build a basement, depending on overall square footage.<\/p>\n Builders use crawl space foundations when a regular basement isn\u2019t a possibility, such as on a waterfront property or where the ground is sloped. Crawl spaces are also the foundation of choice in areas where the ground is prone to excessive dampness or to termites.<\/p>\n Hot and humid climates are not<\/i> a crawl space\u2019s best friend \u2014 especially if it\u2019s an older home<\/a> and the crawl space is ventilated. The excessive moisture can threaten the integrity of the wooden structure components, which can lead to rot. \u2018<\/p>\n The average cost to replace rotted support beams can cost between $1,500 to $5,000<\/a>, depending on what material you are using (wood or steel) and how accessible the problem is to repair.<\/p>\n \u201cIf there\u2019s a water issue in any way, the combination of that and poor ventilation<\/a>, you end up with mold and mildew that rots the floor joists. Then you also have the health issues because you\u2019re walking on a floor with a lot of mold underneath,\u201d Reeds explains.<\/p>\n When the moisture problem isn\u2019t addressed, the crawl space is the perfect place for microorganisms like mold and mildew<\/a> to multiply. Should the air from the crawl space circulate throughout the home, the harmful microorganisms and bacteria can as well. This can spell disaster for residents of the home who have respiratory problems or allergies!<\/p>\n Crawl spaces that aren\u2019t sealed appropriately are susceptible to pest intrusion. Rodents and small animals are attracted to the warmth and moisture found there. A pest infestation<\/a> can cause air quality problems due to their dander and fur, but their droppings are also a health issue, too. Along with small animals, insects like termites can cause damage to the structural elements, HVAC ducts, and wiring.<\/p>\n Crawl spaces that haven\u2019t been sealed properly or insulated well are going to be a burden on the heating and cooling systems. When the outdoor air is hotter (or colder) than the indoor air, the furnace or heater is going to have to run longer to maintain temperature, and vice versa.<\/p>\n You\u2019ve found a home that you want to make an offer on, but it has a crawl space. Should you go ahead and make an offer?<\/p>\n![\"A](\"https:\/\/www.homelight.com\/blog\/wp-content\/uploads\/2020\/08\/what-is-a-crawl-space-house-666x381.png\")
<\/a>What is a crawl space: the long answer<\/h2>\n
Ventilated crawl space vs. conditioned crawl space<\/h2>\n
Ventilated crawl spaces<\/h3>\n
Conditioned crawl spaces<\/h3>\n
![\"An](\"https:\/\/www.homelight.com\/blog\/wp-content\/uploads\/2020\/08\/crawl-space-terms-666x373.jpg\")
<\/a>Vapor barriers, explained<\/h2>\n
Benefits of a crawl space<\/h2>\n
Access<\/h3>\n
Cost<\/h3>\n
Versatility<\/h3>\n
![\"Mold](\"https:\/\/www.homelight.com\/blog\/wp-content\/uploads\/2020\/08\/how-much-can-you-negotiate-off-a-new-build-mold-775x413.png\")
<\/a>Disadvantages of a crawl space<\/h2>\n
Moisture<\/h3>\n
Fungus, mildew, and mold<\/h3>\n
Pest infestations<\/h3>\n
Poor insulation<\/h3>\n
Should you buy a house with a crawl space?<\/h2>\n