BAL Green Screed Adhesive

[Duchard]

OK I could do with some clarity if possible on this one before I plough ahead.

My new floor is being screeded this week (traditional cement\sand mix) and I would like to tile on this asap. I see BAL have the Green Screed available which I could use a week after the lay.

My issue is how much coverage each 15kg will spread?

BAL are stating it has an average of 2.8m2 at a 3mm thickness whereas walls and floors are stating an average 6m2.

At £30 a pop this can be quite substantial as my coverage is 11m2. Anyone know whos right? Is there a min depth?

I will be using large form tiles (600x300).

Cheers.

 

[Gazzer]

If you are using large format tiles then your trowel size should be no less than 10mm IMO. Any smaller and you will have problems getting full coverage.

 

[Duchard]

Thanks Ramic but still leaves me unsure as to how much adhesive I should buy for my coverage of 11m2. 60kg or 30kg..?

 

[Gazzer]

I have only used that adhesive twice and it didnt go far using 330mm tiles. I think i managed about 3.5m2.

 

[DHTiling]

This doesn't help with any salts coming up whilst the floor dries.. and any cracks can still transfer to the tiles.

A crack/un-coupling/vapour equalisation membrane would be my route..

 

[merlecollins]

The Green Screed Addy comes in 25KG bags not 15KG (or at least it did when it first came out years ago!!) :smilewinkgrin:

Like Dave says you should really think about Ditra matting or similar first

I used it as a trial for BAL before it went on general sale and it took forever to set-albeit my job was external- so make sure your room heating is correct before you use it. Never had any problems after it set mind

With a decent 10 or 12mm half moon serator, you'll probably get between 3.5 and 4.5m2 per bag.

 

[Rich]

As above, you will want to use a 10mm trowel to get a full bed. Cant help on the coverage Im afraid as Im a Mapei man but make sure you use a suitable grout, normal grout will not stand the salts from the screed.

 

[Duchard]

Ok first thanks for you replies. Much appreciated.

I have to say I'm a bit of a newbie when it comes to tiling. I have tiled my existing kitchen walls ok using a small brick sized tiles and it looks fine.

I havent tiled a floor before but want to give it a go. I appreciate different people have different methods, advise, etc but I'm now confused as to what the recommnded way to tackle my floor would be.

I came across the BAL Green screed product by surfing around and this looked to me like the best option in my case. Now however I'm informed I should be using a membrane before I set any tile adhesive. I'm going to be also tiling me new wetroom area after the kitchen sorted and for this I was looking at the Dura CI membrane (wetdecs) for the floor here (new screed also). Am I right now in thinking it doesnt matter if this is a wet room or not but the fact that its a new screed and may "move / crack" in the future?

If I do layer a membrane to the kitchen area should I then also use the BAL green screed or should just a decent tile adhesive be adequate with the membrane? I see BAL also do an adhesive specifically for concrete screeds (anti fungal), would this be ok as its cheaper than the BAL green?

Apologies if this sounds like amatuer questions but I find these forums invaluable when it comes to DIY prep.

Thanks again for all your comments.

 

[White Room]

I've used Green screed addy on a screed 7 days after it was laid and never had a problem, your choice at the end of the day though

 

[Rich]

The uncoupling membrane will take movement in the substrate and bridge cracks in the screed, but it can also be used as a waterproofer. You can use an uncoupling membrane over the screed using a single part flexi adhesive.

 

[Stephen@Weber]

As a general rule of thumb for coverage I was taught that 20kg would tile 20m at 1mm thick, 10m at 2mm thick and so on, obviously doesn't work with light weight products.