Hi All Like to think of myself as a fairly competent DIY'er but seem to be getting various advice for what I thought was a simple question. I have a raised patio at the back of my house. Its 8m long x 3m wide and need 50mm deep so 1.2 cubic metres to create the base So far I have layed about a 70-80mm MOT type 1 sub base and compacted it down. I was then trying to work out how much and what material I need to create the base suitable for laying the tile. I was looking at a mixed aggregate and then adding cement but the man from Jewson said that as I have already done a sub base I just need a sharp sand and cement mix. So is that right, how much material do I need and what mix should I do. I have purchased a 2nd hand mixer to make my life easier Cheers all
4:1 sharp sand & cement,but porcelian tiles need a SBR slurry primer so they adhere to the mortar bed. http://www.pavingexpert.com/bond_bridge_01.htm http://www.pavingexpert.com/ceramic_01.htm
Just to throw you a curveball, there are systems where you don't have to stick them down at all: https://www.tilemountain.co.uk/blog...lab-tiles-using-adjustable-support-pedestals/ Can't say anything about them, not my area of expertise, but I saw them on another forum and thought them interesting at least...
Seen them,but never used them, identical to the ones used for timber decking. I could be wrong, but can't them working on loose shingle,as in your link,would think they eventually settle,also been taught to lay paving on a full mortar bed to support slab, those pedestal only at the corners, isn't there a risk of slab breaking with say a heavy chair,table,etc.
I think they need a compacted base at least, like you say, and often a concrete slab. Much more common in Europe, Italy in particular? It does sound like you could end up cracking one with a heavy blow from something in the wrong place, but no idea how they fare in real life.
Thanks so a sand and cement mix is fine that's great. Once the base is dry I was ls going to use a specialist tile adhesive from Mapei or Bal. I assume that would be suitable.
Mot base, use an exterior porcelain primer on the back of the tile like you say and a full mortar bed. I’ve been back to a job today that I did a year ago and it’s as solid as concrete!
Thanks. For total disclosure my plan was to lay the same/cement top layer, maybe draw a slight key into it, let that dry and then get the tiler to come in an lay on top of the dry base with special adhesive as required. Don't want to assume anything but just want to check with the experts.
Either... lay an mot base, lay your porcelain on top of this on a sand and cement wet mix. Full bed. Primer on back of tile Or... 4 inch concrete base, lay the porcelain on top of this with your special adhesive or sand and cement full bed. I wouldn’t lay a sand and cement bed, let it go off and then get the tiler in. That will create a pointless layer that’s only going to be 30/40mm thick. It will end up been uneven and make the tilers job harder. If you’re laying that bed to go off you might as well lay the tiles straight on it while it’s wet