Can I use a leveling compound over hardiboard or duroc.?

Question

I h ave a 3/4 T&G OSB as subfloor over a 24in oc truss floor. I planning to use a electric floor heating system and would like to use the self leveling to cover the heating mats and than tile over it using 18x18 travertine tiles.

Answer 1

You can, but why do you have Hardiboard or Durock under the gypcrete?  That can be applied directly over the mat which will be applied over the OSB.  Your floor system will easily support the load.  The trusses are engineered for a minimum of 40 lbs/sq ft. live load.  You won't come close to that.  Hope this helps.

Answer 2

we are talking about a lot of weight here. leveling compound is nothing more than another name for cement. it just uses a finer texture of materials and is really not meant as a ''stand alone'' product. it is usually put over concrete to smooth things out. the concrete provides the strength.

Additionally your floor beams are 24oc rather than16 oc (even better would be 12oc for this project)

And you did not mention the unsupported lengths between supports.

maybe you need to discuss this with an architect before you get yourself into trouble.

Answer 3

Look at FlooringGuide.com under Electric floor heating systems

Answer 4

The method that you are talking about is a common practice the tiles and cement are Heavy but you are dispersing the weight evenly across the floor so there is no more or not much more than 5lbs per square ft  which a is very reasonable amount. I would be more concerned if you were gonna put a King size water-bed in the middle of the room.

Good luck with your project.

Oh yes you can put self leveling compound  over Hardi board over any backer board

Answer 5

Of coarse you can.  Plenty of strength!

Answer 6

i agree that is alot of weight never seen floor joist that r 24 in on center they should be at 16 in. on center i would check with a pro. before u even do that cause of the weight load and also u need to have a electrican hook up the infloor heating so please contact a few people beforeu even do it