Guest bath stone seat

In remodeling the guest bath, the theme is Zen Spa.  We had an odd corner in the bath that needed something.  To match the feel and also compliment the floor, we decided to create a fixed seat made with a stone slab to fit.

Below are a couple of pics of the finished seat.  The seat is also heated as part of the heated floor system.

This is actually very simple to do and requires only basic framing skills, basic framing materials & tools, and tile work tools. 

The first step was to create a frame work to support the slab as well as the weight of a person sitting on the slab.  The frame work was done prior to drywall.  Be sure your frame work can support the needed weight.

Do not just have studs nailed between the main studs.  Make sure you have legs going all the way to the bottom stud plate then run cross-studs to create the seat frame.  We tested the frame by having Jody and I stand on the frame.  We added our weight and figured the framing could support a minimum of 400 lbs.  The weight of the stone, thinset and person sitting would be under 300lbs.

The wire in the below pictures is the heating wire coming up from the floor.  More on that later.

The heated wire called for being completely encased in thinset or concrete so that it does not burn out.  We completely encased the wire in thinset.

Next we placed the Hardie Board on top of the frame and ran the wire through a hole we made in the Hardie Board making sure to stuff the hole with thinset.  We had precut and drilled the Hardie Board prior to mixing thinset.  We used 1/4" board and screwed it to the frame using the correct type screws to work with this material.  We then taped the wire to the board with metal tape to set it up for heating the stone seat.

Jody spread thinset on thick to adjust for the irregularity of the stone and to cover the heated wire.  She then notched it with a 1/4" notch trowel.

Before mixing the thinset we cut the stone to size.  I forgot to take pictures of us cutting the stone.  We used the Hardie Board as a template to cut the stone.  We wanted the stone to stick 2-3" past the drywalled frame.  I used a standard circular saw fitted with a diamond blade for wet cutting.  Outside I setup the stone on a couple of saw horses and supported its weight before, during and after the cut.  Using a cutting guide Jody took the hose and sprayed a light stream of water on the blade as I took 4 passes to cut each side going a 1/2" deep per pass to cut the 2" stone.  This is messy and wet so dress accordingly.  Go smooth and slow.

Last was to place the stone on the frame. Go slow, get a helper, wear grippy gloves and sturdy shoes.  You do not want to drop this on your foot.  Don't ask me how I know.  Once the stone is placed, press down and let some of the thinset squeeze out the front under the stone.  Then you can use this thinset to fill the gap under the stone and add more if needed.  Make sure to paint or seal this thinset once dry so that mold will not grow on it over time.

So the heated wire...
I cut a channel in the corner of the wall under the frame to run the wire up to the seat and then filled the channel with thinset.  Paint or seal this too once dry.

So there you go.  No contractors, only basic tools and skills needed.  We went to a stone quarry to find a stone that was the right size and thickness and was also flat to sit on.  We will seal the stone with the same sealer we will use on the slate floor.  The stone cost us $30, all rough in materials, thinset etc would be approx $50 but these costs are spread out into the whole project of the bath for us.  Now Jody and guests have a warm or cool spot to sit on in the bathroom.