| Crawlspaces are one type of home foundation | | | | In the summer, the air in a crawlspace is generally |
| system used by modern builders. A foundation can | | | | cooler than the outside air due to the constant |
| be a poured concrete slab, a dug basement with | | | | temperature of the earth. This cool air draws the |
| concrete walls and floor, or a crawlspace. A | | | | moisture out of hot, humid air. This moisture later |
| crawlspace foundation consists of a footing and a | | | | condenses on the underside of framing, on cool |
| wall. The footing is a trench dug in the earth that is | | | | crawlspace walls or on the floor. This is true of all |
| lined with rebar and poured full of concrete; footing | | | | ventilated crawlspaces, even those with current, |
| dimensions vary based on application. The walls can | | | | self-activated vents. The problem with the vents is |
| be made with concrete blocks or poured concrete | | | | that they are based on temperature instead of |
| walls. Block walls are for shorter walls while poured | | | | humidity and the problem in most crawlspaces is |
| walls are for taller applications. A crawlspace is a good | | | | humidity! |
| choice for uneven terrain, situations where a | | | | The solution is a closed crawlspace. Research by |
| basement of slab are unsuitable, or to elevate a | | | | Advanced Energy in North Carolina has shown that |
| house to guard against flood damage. Crawlspaces | | | | closed crawlspaces suffer from none of the moisture |
| are also a more economical option than basements or | | | | problems of ventilated crawlspaces; closed |
| poured slabs. | | | | crawlspaces perform better in the harshest |
| As the way we build homes is constantly changing, | | | | conditions than ventilated crawlspaces do in the |
| the crawlspace has undergone an evolution in its | | | | mildest. Closed crawlspaces also stay more humid |
| forms through its existence. The modern house | | | | during the winter which reduces the drying effect on |
| began as four walls with a roof on a dirt floor. Raised | | | | construction materials and unpleasant side effects like |
| floors arrive shortly thereafter with a wood platform | | | | drywall nail pops and hardwood floors buckling. |
| becoming the method of choice. Stone foundations | | | | Closed crawlspaces are also more energy efficient |
| are common in older homes. Older homes built with | | | | than ventilated crawlspaces. Research has shown |
| concrete foundations generally employ a ventilated | | | | that closed crawlspaces with floor insulation used |
| crawlspace. Energy efficient green homes in 2010 | | | | 15% less energy and ones with wall insulation used |
| have an insulated foundation and closed crawlspace. | | | | 18% less energy. In 2004, this was a savings of |
| Many homes still in use are built on stone or rubble | | | | between $87 and $103! Energy efficiency gains are |
| foundations. These foundations are generally dug into | | | | thought to come primarily from the relation of |
| the dirt and made of stacked stone and rock with a | | | | moisture to human comfort. A drier house in the |
| wood platform built on top. One house I've visited | | | | summer means the thermostat can be set higher |
| has a separate stone foundation for each of the | | | | while more moisture in the winter also equates to |
| three additions! These types of foundations present | | | | less waste energy and less nosebleeds! |
| a host of problems including easy access for | | | | Closed crawlspaces are an integral part to the energy |
| termites, easy access and shelter for rodents and | | | | efficient green home in 2010! They benefit |
| insects, difficult access for humans to inspect and | | | | homeowners by reducing moisture levels and |
| repair problems. Typical solutions to crawlspace | | | | associated problems like mold and rot. This protects |
| problems in older homes with rubble foundations are | | | | the health of family members and safeguards an |
| typically labor-intensive and long in duration. | | | | investment. Closed crawlspaces also reduce monthly |
| Ventilated crawlspaces are the most common type. | | | | operating costs by increasing occupant comfort. |
| Ventilation was once thought to be a solution to | | | | Saving money and being more comfortable at home |
| problems in rubble foundations like moisture and mold. | | | | is the easy choice! |