I have been ask to custom build a handy cap shower that will have to be sturdy enough to handle wheel chairs and really heavy wieght with this I have reinforced the floor as well as set a 3/4 plywood deck now the finish can't use tile I must use mortor and sealent to with hold the wheels of the chair wiil mortor hold or must I use cement and spry poly over the finish to dran and will this work??

Have you ever done a custom pan at all before? Custom pans are usually not a great DIYer project let alone a handicapped shower pan. Are you insured and bonded?

Absolutely, mortar will hold wheel chair.

You are not asking the important questions. So I will ask you:
1. Did you drop the floor in your new handicapped shower so handicapped person can roll in with wheel chair ?
2. What were the heights of the shower valve, seat and handi-bars ?
3. What did you do in regards to shower door ?

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