New By-Law for Balcony Tile Replacement

I am in Queensland

I have to create a new By-Law to define cost split between owner and Body Corp. Tiles are property of the owner. Waterproof membrane is property of the Body Corporate.

Existing adjudications define responsibilities for maintenance and repair of each, however to clarify the cost share I would like a concise By-Law.

Is there a suitable By-Law in existence?

My initial proposal is:

When an owner chooses to retile their balcony or courtyard including replacement of the waterproof membrane, the Body Corporate will pay the portion of cost applicable to the replacement of the waterproof membrane.

Any suggestions?