Ceramic Tile Deflection Calculator

How to fix floor deflection for ceramic tile.

Ceramic tile deflection calculator.

Calculating deflection many tile contractors can judge a floor s deflection by walking around. Enter your floor joist information and then hit calculate deflection to find out your floor rating. If you have engineered truss or i beam type joists please do not use this calculator. Ceramic tile installations require the floor areas over which tile is to be applied to have a deflection not greater that 1 360 of the span when measured under a 300 lb.

Deflection or bounciness can cause tiles and grout to crack or come loose and the tolerance depends on what type of tile is being installed. For instance ceramic tile can withstand more deflection than natural stone. A heavy concentrated load can exceed l 360 between joists. It is for this reason that recommendations for floor rigidity are not based on deflection measurements but on empirically established methods found to work over normal code construction.

Recent research has shown tile to fail under some conditions when the floor is more rigid than l 360. Joists are almost always laid on standard spacings 12in 16in 19 2in or 24in. The apa ews has voluntarily raised the minimum deflection of its systems to l 480 33 stiffer that conventional framing requirements for ceramic tile. In fact failures at l 600 have been observed.

Whether you are installing stone or ceramic tile over floors and walls there s one thing to consider. Learn more about it here. Matthew the ceramic tile institute of america prefers deflection of less than l 360 and states. Concentrated load see astm c627.

Deflection of bare plywood and osb comparable to the robinson l 360 deflection can be estimated by calculation but the addition of tile systems creates a stiffness change in the floor assembly that is impossible to estimate e g. All floors deflect or move to some extent but if. However when considering deflection for tile one needs to also consider deflection between joists. Larger tiles make for a stiffer floor than smaller tiles.

This calculator is designed to work with dimensional lumber only. The tile council of america recommends that deflection be limited to l 360 l span length in inches under total load for ceramic tile.