Jill, the main risk is that if the original bathroom was done before the 80's it most likely won't have been waterproofed. That will mean the water may be damaging the subfloor and you won't even know about it (costing $000's to fix) BTW If you're looking for inspiration for your bathroom look checkout 101 kitchen & bathroom design ideas. Best, Richard@themakeovergroup

Would cutting off the old metal strip flush with the tiles be what you want? If so I have found my little Dremel tool the most hand tool for this type of job. Just needs a bit of patience and selection of the right cutting wheel.

You can lay tiles directly over tiles. With the concrete look on trend at the moment, there are many concrete look tiles to choose from. I know you have said the original tiles are in excellent condition, but please make sure that they are glued extremely well to the slab. Tap over the tiled area and if you hear a hollow or drummy sound in any areas, it is an indication that the tile and tile glue is coming away from the slab and it is not ideal to glue over the top of them. Ployflor has concrete look flooring products. Sexy Floors is another company that have a product which can be laid over existing floors. There are quite a few options available for a concrete look over tiles but it may depend on where you live as to whether there are businesses in your area that offer such options. I suggest doing a google search in your local area.

Hi Liz, I understand your concern about waterproofing. I guess it depends on who does it. I'm extremely thorough. The last time I waterproofed I read every piece of technical information from the suppliers. When I went to order the materials, I asked for things that even the suppliers did not know was in the recommended procedure. I'd warrant my own detailed waterproofing over some tradie in a rush to get to the next job. Not saying they are all like that, but I value and trust my own approach as well. In terms of a certificate, a workaround for a through DIY job is to take detailed photos on installation, similar to what a Building Certifier would be looking for on inspection (not that we can rely on Building Certifiers nowadays either)!!!! My point is that a certificate does not necessarily guarantee a thorough job. Just ask the apartment owners at Mascot..... PS Liz good point on the visibility of a clear 50mm threshold, versus a barely visible one where the toe can scuff...