Most homes are fitted with 5/8" sub-floors either in OSB (Oriented Strand Boards) or plywood. Now we all know that when we walk on this type of sub-floor, it will flex. Ideally, another layer of 1/2" plywood would be sufficient to take the weight of a large person and bringing the floor thickness to 1 1/8" Sub-floor flexing will cause ceramic tiles to crack.
This method of fortifying the sub-floor causes a few problems. It will create awkward steps leading to the areas where tiling has not been done. There will be a need for transition's that will have to be custom made. It will also be a tripping hazard as one traverses to the other parts of the house.
There are a few products out in the market that will address the problem of sub-floor flexing. The first one I'd like to mention is the Schluter Ditra product, better known as the Ditra Mat. It is an orange perforated mat made of plastic that when laid on to an inferior grade sub-floor, will prevent tiles from cracking. As many of you may have seen. Mike Holmes uses this in his TV home shows. The installation of this product requires a bit of proficiency in tiling.
Another product that all you DIY (Do It Yourselfer's) might want to consider is the Custom Building Products EasyMat. The EasyMat is a straightforward way of installing a crack prevention membrane on inferior grade sub-floors to prevent tiles from cracking. It is made of a high density Styrofoam material that is easy to use. The roll covers 40 sq. feet and comes with a bottle of primer. What a DIY does is to make sure that the sub-floor is nice and clean. Screwed down tightly to the floor joist and painted with the primer with either a roller or a brush.
The EasyMat is a peel and stick product. All you have to do is to adhere the EasyMat by peeling the paper off one side of the roll and sticking it on to the dried primed sub-floor. Make sure that no bubbles are trapped underneath the EasyMat. Once the EasyMat is laid out nicely on the floor, tiling can begin.
More on the EasyMat and its related products that will offer a lifetime warranty in my next blog.