How to calculate amount of adhesive & grout for heated floor

[keithjeb]

As title really, when it warms up a bit I'm going to be tiling the conservatory, floor area is 11.5m2 and we'll be using 500x500x10mm ceramic tiles with 5mm spacing.

I know I need to use a bagged adhesive, but I've absolutely no idea how much of the stuff I'm going to need. I'm putting **** heating underneath it, but I don't know if this will increase the amount of adhesive I need or not.

The plan is to use a 10mm half round trowel (what I have, though I'm not averse to buying a new one if needs be).

Some recommendations on the brand of adhesive to use would be great as well!

Thanks,

[royaloakcarpentry]

Have a look at this store locator for Nichols and Clarke to see if they have a store near you, as I use products from them. If you have I can advise on best to use.

http://www.ncdirect.co.uk/index.php?p=sl

[keithjeb]

I'm in manchester, so the nearest is stoke, not an epic trek if they're particularly good value (going to end up spending the guts of £150 on adhesive/grout I reckon.) But if I can source something from topps/tilegiant etc thatd be good.

[royaloakcarpentry]

Topps tiles do Bal products which are good........try jewsons though as they also stock Bal and might be cheaper.

It is better to use a self levelling compound to cover the comfort heating rather than doing it with tile adhesive.

If you do use nichols and clarke then this is the adhesive to use http://www.ncdirect.co.uk/index.php?p=pr&id=9837 (click on the 4th product along in the top row) it only comes in 20Kg bags (available in grey or white) and will be touch and go as to whether you just scrape by with one bag or run into two bags. If you are inexperienced with rapid adhesives then get two bags. This is one of the best adhesives on the market and N&C produce it for a lot of other ''manufacturers'' but at a weaker strength.

Whether you use Bal or Nicobond products you will be safer to get 40Kg unless you can get a 10Kg bag. use a primer which is suitable for the adhesive and also the grout which complements it.

I did a kitchen floor earlier this month and the client got all the tiles, underfloor heating, adhesive, grout etc from Nichols and Clarke and the manager gave him a 25% discount which peeved me off, because that is more than they give me lol.

[JK Decorator]

Topps are the dogs!!! They'll work out quantaties of everything you need and they're more than happy to give discounts, Also they do they're own stuff which is nice to use, not as nice as BAL tho. They'll refund per tile as apposed to unopend boxes.
So much cheaper than jewsons and they know what there on about.

[keithjeb]

Will head to the builders yard i've just noticed down the road as a start, the website says they sell bal.

Just to confirm 40kg of adhesive and say 20 of grout should give me enough with some over?

Unfortunately the bargaining power has been reduced a bit by the mrs buying the tiles already using clubcard vouchers.

[royaloakcarpentry]

If they do Bal in a 10Kg bag then get 30Kg as this will be enough. 5Kg of grout should be enough........................Sorry to say that I know coverage by size rather than weight. It will have the coverage on the bag of grout.

I hope the wife has bought decent tiles, given the size of them and not cheaper ones that curl up once laid.

[keithjeb]

Don't say things like that, how can I tell? Think they were aabout 7 quid a go

[royaloakcarpentry]

Don't panic, they don't curl like pixies boots.

You can only really notice it when you grout. You can lay tiles totally flush but then when you grout some of the corners are no longer flush to the next tiles.

Funnily enough, I haven't a clue what causes it and have never asked what actually does. It can happen with cheap or dear tiles.

[MSCPlumbing&Heating]

Hi. There is a website that sells "Lash Clips" type in tradetiler to google then look for "Tile spacers, wedges and pegs" and youll see these lash clips. They are supposed to help with keeping your tiles flush. Not a bad price either. It may help more if you have a cheaper tile.

MSC

[royaloakcarpentry]

lash clips are a rip off and already there are lots of problem installation as a result of them. You only need to scan the net to find out.

there are other problem solvers to get tiles flush on the market also and all have pitfalls.

proper tiling technique, all the way is all that is needed. As well as some tiles curling after laying, you also have tiles which are not flat at finish stage of manufacture. tiles not square also. None of the DIY help gadgets take that into account.

[keithjeb]

Going down wise i should be OK, and the room is square and a nice fit for the tiles.

By proper practice i assume you mean start in the middle and take it steady to get each one level. Nothing particularly special about big tiles is there? (Only done walls and a porch floor before)

[royaloakcarpentry]

Starting point doesn't have to be the middle of the room. If you think about it, with a bathroom you want to start full row at furthest point from door and work back. Just add in, that obviously means full row and cut tiles other side of it and not starting with full row from bath, wall etc.

Centre of tile should be in line with centre of door opening, but again this depends how it works out with cuts to walls etc. That is where the setting out comes in to play and what looks more pleasing to your (or the Mrs) eye.

With rapid set adhesive it helps if you set out and do as many of the cuts down one side and end before you even mix any adhesive.

By proper practice i assume you mean start in the middle and take it steady to get each one level. Nothing particularly special about big tiles is there? (Only done walls and a porch floor before)

As you have said as regards to getting the starting point level and tiles around it, then it should flow a bit quicker by using the level as a straight edge. Every so often take a tile back up and check the underside of it to make sure you have a good contact between tile and adhesive. ideally with the size of tiles you ought to back butter then anyway. (Adhesive on floor and thin layer of adhesive to back of tile, then lay tile)

If you decide to try lash clips then be very careful because if you pull a tile upwards with the clip then it will leave a void under the tile which is a weak spot.

[Rookery]

The heat loss in a conservatory is considerable so this is the method I use in these situations, assuming concrete or sand/cement screed floor.
1. Prime floor with Mapei Primer G.
2. Fix 10mm Marmox or similar insulation board with Mapei Keraquick.
3. Fix UFH mat or cable according to manufacturer instructions.
4. Cover mat/cable with latex levelling compound.
5. Fix tiles with Mapei Keraquick (Or Keraflex Maxi if you want a slow setting adhesive) using minimum 10mm notch trowel and back skim the tiles too.
6. Grout with Mapei Ultracolor Plus.
BAL or Weber are good quality alternative brands. All these can be bought at CTD Denton.
Make sure you condition the UFH too. Get a qualified spark to connect to mains to comply with part P building regs.
I would expect to need 3 x 20kgs adhesive and 1 x 5kgs grout + silicone for the perimeter.

[keithjeb]

Been looking at prices for the boards, jeebus they're expensive. Looks like its getting put off for a couple of pay days rather than just one!