USG’s DUROCK Tile Membrane, a popular alternative to traditional backerboard, is a thin, waterproof, vapor-permeable membrane used under tile in residential and light-commercial floor and wall applications.

USG’s LEVELROCK Brand SRM-25 Sound Reduction Mat, topped by LEVELROCK Floor Underlayment, provides a complete sound reduction system in all types of flooring applications.

As a contractor, you spend time and money to advertise your services. Finally, someone calls you to discuss a bid on a new ceramic tile floor. The potential customer knows he wants the tile floor installed in the family room, approximately 600 square feet (30 feet by 20 feet). He has already been shopping and selected a tile, (12-by-12 porcelain), because it is low maintenance. The potential customer would now like it installed for a more “reasonable” price than what the tile store is offering.

Surely you can beat the price and pick up that business, so you agree to meet the customer tomorrow, look at the job and get the deposit. All is well in Pleasantville, or is it? Be sure to take your 2007 edition of the TCNA Handbook for Ceramic Tile Installations with you to determine what is involved in the installation.

The first thing the customer tells you is that he doesn’t want a big “toe-stub strip” in the doorways and wants very small grout joints, preferably something not too visible. He tells you that he has heard that you can use something new called a “membrane” instead of traditional backerboard, and that is what he thinks he wants. In addition, the customer has read on the Internet the information about tile installations, thus making him an “expert.” He now expects you to conform to his newfound knowledge.

Can you say, “Look out” quickly enough to escape this fate? Most consumers have absolutely no idea how much important information you as a professional tile installer need to know before you decide how to install their tile. They just want the job done for the least amount of money, guaranteed/warranted in writing for life, and oh, yes, finished by next Thursday because they have a big party planned for that family room on Friday night.

FIBEROCK brand AQUA-TOUGH underlayment from USG provides superior performance, versatility and quick installation in a variety of residential applications.

Let’s begin examining the requirements of this job:
  • Is it a wood subfloor or concrete slab? Both have certain necessary treatment questions that must be asked before moving forward. Membranes can work on both most of the time, but traditional tile backerboards cannot be installed properly on concrete slabs.
  • If the floor is a concrete slab, are cracks already visible? How old is the slab? Any visible moisture that needs to be addressed? Some membranes can accomplish both waterproofing and crack isolation.
  • Is the floor flat and level or in just slightly rough subfloor conditions? Again, depending on if it is wood or concrete, there are different methods to deal with the situation. ANSI standards specified subsurface tolerance is 1/4 inch in 10 feet and 1/16 inch in 1 foot. ANSI also specifies proper spacing between plywood (or OSB) sheets, which is normally 1/8 inch.
  • How many windows/doors have outside exposure and which direction are they facing? Direct sun exposure affects the expansion joint (movement joint) requirements.
  • How is the room interior lighted? Some lights produce shadows and undesirable effects on ceramic tile floors.
  • What is the longest run length? Again, expansion joints (movement joints) are needed in critical areas.
  • Installing porcelain tile requires specifically recommended setting materials. If you use a membrane system, there may be additional conditions required from the setting materials manufacturer.
  • Who will provide and pay for the protection of the new tile work while the setting materials are curing? This needs to be discussed at the outset, especially in light of the earlier remark of the tight turnaround in getting the floor ready in time for the party.

As you can see already, you must take into account the many considerations that need to be made by you, the professional tile installer, before you can even give the customer a price quote. To help create even more value for your customer, you should also help him or her understand the tile they have selected and how it will work and hold up in their particular application. Hopefully a professional salesperson has already assisted the customer with this part, but you might want to be proactive and ask.

A porcelain tile can be unglazed, glazed, or honed and polished to a very high shine. Each works great in proper applications, but each has certain restrictions that also need to be discussed.

No article in a magazine can make up for good, solid training and hands-on experience from a quality training program. The Ceramic Tile Education Foundation ( has an exceptional program of quality training that can lead up to an actual tile installation certification program. The bottom line of this story is that you might be biting off more than you can handle and creating a huge problem for yourself if you don’t know and understand what the requirements are for the job you are estimating.