In our recent build we used cut down wall tiles (same as used on our bathroom walls) at the bottom edge of the wall in our toilet and laundry. We tiled the walls up to about 2400 in the bathrooms.. Our floor tiles are a concrete look grey, and the wall tiles are a matt white, both originally 600x300. Looks fine, as our wall paint is also white.

I would recommend going a darker colour too! We have done it several times with clients who (like yourself) can't see what the finished concrete aggregate will look like until afterwards and the darker the better we have found. Like Zaffa said, it would be amazing if you could extend the concrete into the bathroom, as that can be absolutely beautiful and this aggregate look is a fantastic addition to a bathroom. However if you want to break it up I would go for a dark charcoal (large format) tile so you don't risk clashing colours. Darker bathrooms are really stylish so you don't risk sacrificing on style. Don't hesitate to contact me if you need any help selecting specific tiles as we know how overwhelming it can be and are happy to help. Best of Luck, Jordan from JFI Studios!

a section of the floorboards can be removed and install compressed cement sheet in the hallway and the waterproofing extended over the new flooring and tiles laid over the original floor and cement sheeting without needing to pour an extra slab

Hi Robert, first question, any fine line cracking in between grout or is it all the tiling/Concrete base pretty stable ? Paints and Sealers certainly can do the trick ? but there are other options depending on your budget and future plans. If you are handy type of person, you might consider ripping up the tiles and re starting with a nice Concreting grinding and sealer, these days grinding / Honing is done in such a way its not that slippery anymore, or do a Spray pave that does give you that Gritty feel to it but can leave you with a more difficult surface to maintain to keep clean..i guess it depends on your circumstances.. just a few thoughts to leave you with.Good luck Andrew