I'm installing hardibacker on top of a plywood floor in preparation for ceramic tile. My first question is, when preparing the layout of the board onto the floor, should I be concerned with the dimensions of any board I cut. For example, assume a floor width of 10'. The boards are 3' in width. This would mean that I could lay three full sheets side-by-side and cut the fourth to 1' (ignoring the 1/8 spacing between boards for arguments sake). Is 1' too narrow? Is there a minimum? Hardibacker's web site doesn't address this issue. My second question is, when I'm putting the thinset onto the plywood do I cover the spacing between the plywood sheets? If so, won't this hinder the expansion and contraction of the plywood? Thanks.
a minimum width of the bthat I should be concerned with