Concrete floor finish question

[Nixdorfer]

Hi, we're currently having problems with the firm who's buildinng our conservatory

I've got a thread going on the plastering, now time for the floor

If the invoice/bill says "smooth concrete floor" what would you take that as being? Our is just tamped concrete which is rough a bears a*** TBH and not that level based on the way the water sat when it rained.
They didn't attempt to float it except for a 1m section on one side.

I've tried a few times to pull them up on it but they keep saying that's what they class as a smooth finish and they do them all like that.

Surely 'smooth' concrete means at least floated?

 

[noseall]

tamped concrete usually indicates the later use of a secondary screed layer.

is the tamped concrete up to finished slab level or have the builders left it say, a couple of inches or so down?

 

[Nixdorfer]

The tamped slab is up to the finished floor level and inspection cover.

They've not allowed me much so by the time i've put the tiles and underfloor heating on it's actually going to be at least 1/2" over the house floor level

Even if I was to try and self level it i'd have to sort the inspection cover out at its would be too low. I think they have also put the wrong size and type one in

 

[mattysupra]

Im not sure of the new standard, got no paperwork to check with me at home. Most floorcoverings ask for 1-3mm runout in 1 meter. However, i have not met a builder that can get a floor this smooth, dont know why? i dont have a problem doing it, infact i work to 1mm in 1meter on ever job i do!

Make sure they dont use a latex smoothing compound over the concrete, for most floorcoverings you can not use latex as to weak!

Use acrylic based compound and always prime the floor.

You can not use a water based compound either untill the concrete has dried out, but fine and the best to use when dry. Concrete takes on adverage 1mm per day to dry, so basically your looking at about 3 months for 10cm to dry or 6 months for 20cm to dry.

 

[Nixdorfer]

When you say runout do you mean within 1mm-3mm of bubble level per meter? what about the actual smoothness of it, is there a quideline for that?

They don't plan to use any smoothing compound thats my problem, they class is as finished!

Agree with your comments about latex, They used Ardex stuff at work and every time I drop a bolt, spanner or jack a car up it dents the floor. Not ideal for a commercial garage

EDIT: Eeeeeeek about the drying times, ours is about 6" thick as they had to put loads more in to bring up the level after they tried to do it 3" lower than the house originally.

Untitled

• Nixdorfer
• 27 Aug 2008
• 1

Untitled

• Nixdorfer
• 27 Aug 2008
• 1

Untitled

• Nixdorfer
• 27 Aug 2008
• 1

Untitled

• Nixdorfer
• 27 Aug 2008
• 1

 

[mattysupra]

latex in a work shop??? No comment!

Your looking at 6 months drying time, this is an average, could be longer could be less!

And forget level with a bubble, flat and smooth is what we are talking about! If you have a straight edge 1meter long then the floor should not go up or down more than 1-3mm depending on what is being installed.

Where about are you? Maybe you could P.M me the name of the company doing the work, Might drop in to see them and see what standards there working to.

 

[mattysupra]

pics dont look to bad, i have seen alot worse! Still crap tho!

 

[Nixdorfer]

If you don't think the pics look that bad maybe I was expecting too much

I could self level it or lose it in the tile adhesive if needs be but I thought "smooth concrete" would mean something a bit more finished off.

The firm aren't builders just a DG company which is half the prob I think. They seem to have their own standards and rules from what I've seen so far and are usually outside building control.

Thanks for the info though, I'll check out the acrylic stuff if I decide to level it.

Would we have to wait for the concrete to dry 100% before we could put tiles, heating etc down. Would it trap the moisture in if we did it too soon?.

 

[mattysupra]

ceramics are o.k after a few weeks, anything impervious or wood based is a no.

It is hard to tell of pics but like i said ' i have seen worse ' , im not saying there is nothing wrong with it as it dont look the best!

 

[Nixdorfer]

Thanks, had a straight edge on it and its not a million miles off in the majority of it, a couple of areas maybe need tweaking. The rough finish makes it look worse than it is.

Think I'll have to level it myself or lose it in the tile adhesive as I'll be putting insulating boards down at some point. Spoke to them yesterday and they don't seem willing to improve it.

Probably go for the acrylic stuff if I do it as ours floor is going to take ages to dry out properly.

Cheers

 

[mattysupra]

sounds like a plan, only if fitting ceramics tho. You can fit other floorings like amtico, karndean etc if you install a surface dpm first ( you dont have to wait till dry if using surface dpm )