decking

I am working with an elevated deck/screened porch with gaps between each board. I want to enclose it with a Plexiglas like window that is removable so I can enjoy it year round. I am thinking of putting down either a vinyl sheet or roofing tar paper as a moisture barrier, then cement backer board, then porcelain tile.

Little more to it than that Peter, keep thinking.

FLASHIN_G & PITCH These are the two of the most critical issues. When you have acknowledged and adressed these call back. Then we get started. I admire your vision of taking out the windows.

The pitch and flashing are already in place and work fine. No leaks and the water that may get in from side ways rain is very little. The house is 15 years old and it has a new roof on it due to bad flashing. I have also already inclosed under the porch with screening to keep out spiders and such.

3/8 exterior plywood perpinduclar gaped properly, cement board not fiber cement liquid waterproofing, (redgard) modified thinset porcelain tile. Enjoy

Or DITRA or Noble CIS for a membrane.

Thank you both for your suggestions. I will look into these. I am not familiar with Ditra or Noble CIS and will check those out at Home Depot. Joe, are you saying to mix the redgard in the thin set? Will 1/4 cement board be enough over the plywood?

RedGard is a liquid applied waterproofing membrane. It is not mixed with thinset. 1/4" should be adeuqate. Be sure to install all materials according to current instructions. Tape the joints of the cement board with the proper tape. The joint against the house or structure and around the perimeter is a "sealant" joint not a caulk material and is not grouted. A real tile distributor may have this or a building supply house.

Thank you for your help.

Noble's CIS isn't in any of the big box stores to my knowledge. You would have to go to a "real" tile store or order direct from Noble.

DITRA is on hand in most all Home Depots.