What to Put Under Hardwood Flooring

The natural beauty and durability of wood floors makes them a popular treatment in old and new homes alike. Older homes may or may not have used an underlayment beneath the wood. However, new installations--fixed or floating--may need an underlayment for a number of reasons. Before remodeling, consider what needs to be put under your hardwood flooring and the reasons for using underlayments.

What to Put Under Hardwood Flooring


Hardwood floors are noisy. An underlayment installed beneath hardwood flooring will control the amount of noise that comes from hardwood flooring. Underlayments can also provide insulation and protection from moisture that may build below the surface of the flooring. Certain types of underlayments will also be installed for cushion, providing a shock absorber to anyone who walks on the floor.


There are several types of materials that can be used as underlayments for hardwood flooring, including cork, gypsum fiber panel, particle board, foam, Visqueen and vinyl. The type of underlayment you should use is based upon the type of subflooring.

Choosing Underlayment

In order to get the proper underlayment, you first need to consider several factors, such as where you live, what type of subflooring lies beneath, location of the floor (upstairs/downstairs), humidity and moisture levels of the home and the necessity for insulation.

Foam underlayments are not the ideal choice for any home with high levels of humidity or where moisture may come in contact with the foam, as this can create hazardous mold growth. In addition, homes with moisture and humidity issues need underlayment that will prevent moisture from reaching the hardwood flooring to prevent damage to the wood.

An underlayment that provides a sound barrier is an absolute necessity for upstairs rooms, condo units and apartments. Without the sound barrier, life for anyone living below that unit can become unbearably noisy. For homes located in colder climates, an underlayment that provides a thermal barrier will help keep the floor warmer and also assist in lowering energy costs by preventing cold air drafts.

The type of hardwood flooring (real or laminate) will also be a determining factor in the type of underlayment chosen. Manufacturers provide written specifications about which types of underlayment can be used with their flooring product. Using the wrong underlayment material can void warranties and cause damage to the flooring.

Cost Control

The cost of installing an underlayment varies with the type of material and the labor associated with installation. Research and comparison shopping can assist you in getting the best materials for the best prices, especially if you are doing the installation yourself. If you are working with a contractor, it's easy to be swayed into doing things his way--just because he says it's good. Keep in mind, however, some contractors may want to use a material that's easiest to install, and others may want to use the underlayment that will cost you the most so to increase their profits. In order to get what you need, do your research in advance, and do not sign any work orders or contracts until you are certain that your contractor will use the product you request. If she refuses, you do have the option of looking for a different contractor who will work closely with you to get you the finished results you want.

Going Green

Environmentally-friendly materials are fast becoming the norm for new building and remodeling projects. Manufacturers are developing underlayment materials that consist of recycled and nontoxic materials that are formaldehyde-free and non-allergenic. Many building suppliers are beginning to carry "green" alternatives on a regular basis, and there are now "green" building supply companies that sell only environmentally-friendly materials.