Hi Guys, I don't do much work which requires screeding but I currently have approx 40m2 of lvt's in a house to fit. I primed all the areas the other day and went back last night to screed with 300 HD. Went back today to check that it had set ok and it was looking good , only thing was approx 2 of the mixes looked a different colour to the rest(much lighter). I was very fussy about measuring the water (5.5 ltrs)and mixed according to the instructions. What could the reason be for this ? Was I perhaps slightly inaccurate with my mix or could different bags be slightly different ? Cheers Ray
I would say that you added to much water mate. Fballs system is preety accurate at getting the correct amount of powder in the bag. Also if you still have the used bages then you can check the batch to make sure they are all the same. If you ring fball and tell them the batch numbers they will check the batch (they keep samples) However i have issues before (not fball) but with other products that have done simular. I know i have not mixed wrong as my method wont let me add to much water (hole cut in bucket at exact measure so if i add more it drains out and i also have a mixing system that mixes for me and i time how long it mixes for. ) Speak to fball and see what they say, if you dont telll them they cant look into it!
You could well be right, I used the measuring bucket for the water but I was up against it time wise as it was getting dark (no power in the house yet !!) and i didn't want to stop half way through. If i did use too much water it wouldn't have been too much - shouldn't cause a problem should it ? Dont do screeding very often but apart of the coulour difference i was well chuffed with the result - very satisfying !
if you have added to much water and it has still set then you will normally be o.k, however it will not have the shear and compression strenght of a properly mixed screed. All depends on what you fixing/fitting to the surface. If you are laying a domestic vinyl loose lay then it will be fine, same for carpeyts etc also. But if you are fitting karndean etc then you stand a chance that the area will get impressions of high heel shoes etc as teh screed is weaker. BUT in most areas this will be fine. Only comercial heavy wear arreas may be a issue. If your fitting a solid wood and glueing down then i would be worried as the wood can shear from the weaker screed! Anyway, if you are fitting any of the above then get back to me. You can also prime well to bring strength back up.
Thanks guys, went back today to start fitting the tiles and screed is aboslutely rock solid. Its a lesson for me to learn although I couldn't have been far out with the water. Do you guys always follow the mixing instructions to the letter ? Reason I ask is the first time i used Ardex feather finish for skimming over Ply the reccomended mixture turned out far to thick and as such I now water it down a lot more. The screed I used the other night perhaps did'nt flow quite aswell as i thought it would maybe didn't use enough water on some mixes !!
feather finishes and mortars you can mix how you please. All water based Screeding compounds need to be mixed as they say on the bag. 1/2 a litre of water out will make a big difference to the mix.
If you have added more water then the layer of screed that you have applied maybe thicker.I remember (when i was a lad),mars bars had a thicker choc coating but milky bars were lighter.
