Meaning of Subfloor
An underlayment is a type of construction used in many different types of residential and commercial buildings.
As the name implies, an underlayment is an additional layer of flooring that is placed directly on top of the floor joists and then covered with a second layer that serves as the visible floor in the structure.
Using this type of floor construction helps add stability to the floor, as well as improve the chances that the floor will remain level in the long run.
Concrete is often used as a subfloor in bathrooms and kitchens.
Several different materials can be used to create a subfloor. One of the most common is the use of plywood sheets. Plywood subflooring is attached to the floor joists, usually with nails. Sometimes wood glue can also be used to attach the plywood sheets.
Once in place, the plywood is covered with an additional layer of some type of flooring, which may or may not be some type of wood product. Once the top layer is in place, the floor can be covered with carpet or tile.
If the top floor is some type of hardwood, the builder may choose to sand, finish and seal the top layer, allowing the natural beauty of the wood to add character and visual appeal to the room.
Concrete provides a stable base for floors.
It is also possible to use concrete to create a subfloor. This approach is very common in basements and bathrooms. Here, the idea is to use the concrete to create a stable base for the floor, then cover it with stable materials before adding any decorative touches.
For example, a bathroom subfloor can provide the foundation for adding a second layer of concrete which, in turn, provides the means to secure the tiles to the top layer of flooring. The basement subfloor can provide support for a layer of wood that is left exposed, painted, or covered with carpet.
Plywood is commonly used to make a subfloor.
There are two main advantages associated with subflooring. One has to do with making sure the floor remains stable for several years.
The presence of the floor helps to distribute the stress on the floor joists more evenly, which in turn helps slow the deterioration of those joists. A second benefit of this type of flooring strategy is that the chance of sections of flooring shifting and tilting over the years is reduced.
While installing an underlayment does add some expense to the cost of the construction project, that expense is easily justified by years of enjoying a floor that remains level and strong even with constant use.
Floor joists, part of a subfloor.