Floor Tile Deflection

Whether you are installing stone or ceramic tile over floors and walls there s one thing to consider.

Floor tile deflection.

The marble institute of america recommends that total load deflection be limited to l 720 for spans up to 14 0 and a maximum deflection of 7 32 for spans greater than 14 0. Note it gives the allowable deflection based on a fractional span quantity so a larger denominator will yield less deflection. 1 2 the values stated in inch pound units are to be regarded as standard. 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.

In fact failures at l 600 have been observed. All floors deflect or move to some extent but if. Calculating deflection many tile contractors can judge a floor s deflection by walking around. Recent research has shown tile to fail under some conditions when the floor is more rigid than l 360.

Under total load for ceramic tile. How to fix floor deflection for ceramic tile. See the table below. This calculator is designed to work with dimensional lumber only.

For instance ceramic tile can withstand more deflection than natural stone. If that same joist had gypsum ceiling l 240 the allowable deflection is 0 6. Enter your floor joist information and then hit calculate deflection to find out your floor rating. For example the allowable deflection of a 12ft span floor joist with plaster l 360 is 0 4 12ft divided by 360.

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. Stone tiles may be installed with thin set methods a 14 foot maximum span is recommended by the marble. Because ceramic floor tile is rigid and unforgiving it needs a structurally sound immobile base.