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.

Floor tile deflection. 1 2 the values stated in inch pound units are to be regarded as standard. Under total load for ceramic tile. See the table below. Whether you are installing stone or ceramic tile over floors and walls there s one thing to consider.

This calculator is designed to work with dimensional lumber only. Note it gives the allowable deflection based on a fractional span quantity so a larger denominator will yield less deflection. If you have engineered truss or i beam type joists please do not use this calculator. All floors deflect or move to some extent but if.

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. For example the allowable deflection of a 12ft span floor joist with plaster l 360 is 0 4 12ft divided by 360. Calculating deflection many tile contractors can judge a floor s deflection by walking around.

Because ceramic floor tile is rigid and unforgiving it needs a structurally sound immobile base. Recent research has shown tile to fail under some conditions when the floor is more rigid than l 360. For instance ceramic tile can withstand more deflection than natural stone. 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.

How to fix floor deflection for ceramic tile. In fact failures at l 600 have been observed. If that same joist had gypsum ceiling l 240 the allowable deflection is 0 6.