Each type of foundation has its own distinguishing features and sets of terminology to go with them. If you are researching your crawl space foundation, there is a good chance you will come across many of the following terms. Here are some definitions that can help you.

Pier & Beam

Pier and beam is one kind of crawl space foundation in which piers elevated above the ground support beams upon which the home rests.

The piers can be made of anything from steel to concrete to masonry blocks. The fact the piers elevate the beams above the ground is what forms a crawl space.

In some area pier and beam refers to foundations with a concrete or masonry beam around the perimeter that supports the exterior of the home while the piers support the interior. This differentiates it from a classic block and base. In other areas, however, the term is more generally applied.

Block & Base

A variation on the pier & beam. In the classic definition, there is no continuous load bearing wall around the home’s perimeter. If the crawl space only covered by skirting that isn’t load-bearing if at all.

Post & Pier

Another name for pier & beam that was more prevalent when wooden posts were used to support the beams.

Stem Wall

This is an entirely different category of crawl space foundation from the previous three. The stem wall, either a concrete or reinforced block wall, sits on top of the footings along the entire perimeter of the home and provides support for the beams that make up the rest of the foundation

Crawl Space Vent

This is an access point where crawl space air is vented outside, allowing humid air to leave. Sometimes, however, the vents have proven to allow in more humidity than they remove. These are often sealed during the process of crawl space encapsulation.

Vapor Barrier

Vapor barriers generally consist of tear resistant plastic sheeting that is placed on the walls and floor of a crawl space during crawl space encapsulation. Although they are called vapor barriers, these are technically vapor retarders. They still allow a small amount of water vapor through. They are, however, an essential part of crawl space encapsulation.

Crawl Space Encapsulation

The process of sealing off the crawl space to as much moisture as possible to prevent problems caused by high humidity. This generally involves placing a vapor barrier and air sealing the crawl space, including vents. A dehumidifier is sometimes installed as well, and other waterproofing measures could be needed if standing water is a problem along with high humidity.

Joists

The floor joists are generally made of wood and sit on top of the beams in a crawl space foundation to support the floor above. They are exposed within the crawl space and can be adversely affected by high moisture levels.

Sill Plate (or Mud Sill)

The horizontal board anchored to the top of the perimeter stem wall or beam. Joists rest on or attach to it. These can be vulnerable to rot when moisture is high.

Footings

The concrete base that the piers or stem walls sit on.

Shims

If the piers (or blocks, or posts, depending on what term you are using) begin to settle, shims can be placed between the top of the pier and the beam so that they continue to provide support. While wood shims used to be used, modern repairs are done with steel.

Is Your Crawl Space Foundation Having Problems? Call Pierman

If your crawl space foundation is in need of repairs or encapsulation and you live in our Oklahoma service area, contact Pierman today. We are experts at dealing with crawl space foundations in Oklahoma.