A good website is
www.floorheating.ltd.uk for information, loads on there. And if you look through some of the other websites when you do a Google search for electric underfloor heating you'll find much more info, maybe even some videos.
The basic jist of underfloor heating is as follows:
You can buy a cable and lay it out on the floor, or a mat that has the pre-set spaces already on it. Depending on the watts per square meter would depend on the spacings if you spaced your own loose cable rather than choosing the mat.
On concrete floors you'd lay a layer of adhesive down, fit insualtions board, fit the cable/cable mat, then either
tile directly over it with a thicker bed of adhesive if the floor is small enough to bother with the extra fiddling about time, or use a self levelling compound on any floor over a few meters to get the floor looking flat and ready for tiling. Always use an electrician or get the customer to get their electrician in to do the connection to the thermostat.
On wood you'd make the floor sound using plywood or
cement backed insulation boards (like marmox, maybe wedi board) and proceed as above.
Obviously the adhesive and grout is more expensive as it's always flexible, and you have extra products to make a few quid on, and a whole extra layer of adhesive, so any adhesive profit has just doubled too.
You can make a fortune out of underfloor heating installations mate. And customer are always a little higher in class than the yellow pages customers sort of thing.
Epoxy is actually neither an adhesive or grout but acts as both. It can fix tiles and be used to grout them in food prep areas (a requirement by law) and any other hygeine orientated places like factories and hospitols etc (although some other products can also be used in some cases so it's not a case of epoxy epoxy epoxy when an architect or product specifier works on such areas - just due to epoxy costs, but thats a good thing because when it is used again, you get a bit of profit above the normal).
Epoxy is a two or three part mixture with some of the mixture when neat is toxic or somehting (forget the term now) so look into it well.
More common than epoxy fixing is epoxy grouting as even the pub kitchen type market can afford it as an option then to pass hygene regs.
You apply it differently, mix it differently and treat it differently to any adhesive and grout but again a demo would be required to fill you in.
Checkout BAL's Easypoxy as that's an easy application but other brands have something similar too.
Dunno if you can get a topps tiles guy do a demo one time maybe or something if you dont fancy getting a course to show you or something?
If you ask in the forum you'll certainly get replies from both Gaz and Dave who will no doubt find you all sorts of pictures and information about it.
Regards,
Dan