centering a floor

[crazysteve123]

Hi, am in the process of tiling a floor it looks good but whats the best way of run a centre line across the whole floor after setting out and is it best to lay the tiles up the centre first and work outwards....

[grumpygrouter]

I use a chalk line for marking my datum, and no you don't have to start from the centre. You can start from wherever it will be most convenient for where you want to finish. I normally run a parallel line from my datum measured with a gauging staff to a starting point farthest form where I want to end up. You don't want to be treading on tiles you have just laid. Always work away from your start point.

[sWe]

The easiest way to center a floor, is to measure and find out the centre on each of the sides, and then making a line between the opposite marks, but doing that without further consideration can result in very small sliver cuts.

For example, say you have a regular, fairly square floor, where side A is 3m, and side B is 2m, and you want to fix tiles which are 30x30cm in a regular grid pattern with 3mm grout lines.

Side A = 300cm / 30,3cm = 9,9 tiles
Side B = 200cm / 30,3cm = 6,6 tiles

If you just center the surface, Side A will have about 9/10s of a tile along the edges on both sides, while side B will have 1/3 cuts along the edges on both sides. 9/10s is as close to optimal as you get with those tiles and that grout line width. 1/3 is not optimal. To correct that, you'll have to offset the guideline half the width of a tile. That'll get you 8/10s of a tile along the edges on both sides of side B.

Here's the short of it:

If the last whole number of the number of tiles you can fit into a row is UNEVEN, you can just go ahead and mark the centre, because the cuts along the edges of the surface will always be atleast the width of half a tile, or more.

If the last whole number of the number of tiles you can fit into a row is EVEN, you need to offset the centre by half a tile, because otherwise the cuts along the edges of the surface will always be half a tile or less.

Maths. I think I'll write a proper guide on this tonight.


Anyways. The rest as grumpy says. You don't really want to start in the middle of the room if you can avoid it. dry lay a couple of tiles along you guide lines and mark a suitable point to start, and make a 90 degree line with your marking as a starting point. I'll think of an easier way to explain it later.

Good luck.

[crazysteve123]

Thanks for the reply lads much appreciated getting the hang of what your saying well almost

[Varley]

sWe, you a tiler or a mathematician? lol, great advice again mate

[Dave]

I think I'll write a proper guide on this tonight.

Marcus.....you will end up like me.....

[sWe]

Originally Posted by Varley

sWe, you a tiler or a mathematician? lol, great advice again mate

Heh, I told an old work mate of mine about these forums last week. He's got dyslexia, so he isn't really interested in reading or writing things, but he did ask if he could see anything I'd written... Showed my "guides" thread, and he said "dude, you don't belong getting your hands dirty; ever considered giving lectures or some such?"

Originally Posted by Dave

Marcus.....you will end up like me.....

Define "like you" please

[Dave]

Originally Posted by sWe

Define "like you" please

I mean you will be hooked to the forums every spare minute....and clocking that post count up and up and up and up...........dedication marcus and you ceratinly have that...we appreciate your threads soooooooooooooooooooooo much....