Added: 09/20/2013

Over 60sqft master bathroom

Heating system will be install under the tile floor on top of plywood. This is a renovating project.
From our layout example you can see that we recommended to free a part of cable from the mesh to cover the area where heating mat cannot fit, due to width of the heating mat is 20" and at least 1" has to be kept between the rows. Also heating cable cannot be cut.
HTMATKIT-120-60, which includes 36.6ft long heating mat is the best fit for this application.