EXPANSION/CONTRACTION - This product is subject to expansion and contraction with temperature change in the same way that "floating" wood floor systems are; but the process is accelerated due to the fact that the mat is a foamed plastic, and therefore full of air.  As a general rule, allow at least 1/4 inch on all sides between the mat and wall to allow for expansion.  This can easily be covered with simple molding and will work for most installations up to 16 feet wide.  Installations over 16 feet wide should allow at least 1/32 inch per foot of width if the mat is contained by walls or other rigid structure .  For example, a 20 foot wide wall-to-wall installation would require a minimum of 20/32 (3/4) inch of space to allow for expansion.  Along the same lines, if certain parts of your mat are going to be anchored to the ground by heavy objects on top of the mat, you may need to segment your mat to allow for expansion.  See the "Segmenting Mats" page in Tips and Tricks.

High Heels and Sharp Objects - It goes without saying, but we'll say it anyways:  This is just not the right product to install in areas where high heels, sharp pet claws or other sharp objects will be in contact with the floor often.  It will will still pad and insulate your floor, but the appearance will suffer. No manufacturer considers this a manufacturing defect.  It's normal wear and tear, so think about your use before deciding if this this the right material for your particular flooring application. 

A 200 pound man wearing men's dress shoes with a regular heel, will exert less than 30 lbs. pressure per square inch. However, a ladies high, thin heel can seriously damage all types of floor coverings. A 110 lb. woman wearing these shoes can exert in excess of 1,000 lbs. pressure per square inch. These shoes can dent hardwood floors, chip ceramic tile, puncture carpet and pad, and dent vinyl floors. Sheet vinyl products will withstand static loads of up to 75 lbs. per square inch, and Wondermat, being a high density foam, will withstand even less; in the 40~44 lb. range.

The same philosophy applies to chair legs, table legs, etc. The narrower the leg, the higher the risk of an indentation problem. Proper floor protectors are a must for preventative maintenance. The ideal size is two inches or larger, completely flat and composed of a material that will not scratch or stain a vinyl floor. The protectors must rest flat on the floor. Uneven or angled protectors, with only an edge in contact with the floor can cause indentation problems.

Heated Sub-Floors - We don't recommend insulating an entire heated sub-floor with Wondermat. We understand why someone would install a small area mat for a child in a room heated in this manner, but it makes no sense to cover a full heated sub-floor with Wondermat since most of the heat will be trapped by the mat, and that may lead to problems with the underlying floor material.  That said, if your room is heated by radiant coils in the sub-floor, the temperature should not exceed 85f or you may experience expansion problems with the mat. 

In a simple area mat installation, the only requirement is that you allow for expansion along walls and other unmovable obstacles.

STEP 1: PREPARE THE SUB-FLOOR

If you are installing on top of carpet, you may notice that your mat tends to buckle or move around the room.  All carpets have what is called a "Nap," which is simply the direction all the fibers are running in.  You can see this when you vacuum in the "wrong direction" on a carpet.  The up and down motion on the mat, when installed on carpet, will make it want to move in the direction of the Nap.  THE SOLUTION is to install plastic carpet runners on top of the carpet (spikes down!) before laying the mat down.  This will eliminate the Nap movement effect. 

If you are cutting a large mat in an open area, like a trade show mat, you may find a Chalk Line easier than marking individual tiles.
Marking and cutting custom corner tiles may be simplified using a metal Square if you know your way around one.