On 1 July, 20:15, Tim S wrote:
Very interesting day...
Here's the floor:
http://photos.dionic.net/v/public/bu..._0014.jpg.html
If you zoom in, you may just be able to make out chalk contour lines in red
(low) and blue (high). Each line is +/- 2mm by laser.
Well, me and my labourer got 1/3 of it up in a couple of hours. The bond
failures are a clear case of delamination due to:
a) Odd bits - the asphaltic gunk
b) Front of fire and long bit down the middle of the room: In both cases
these are due to there being brickwork under the floor, one I guess from an
old fire hearth and the other was the old garage wall foundation and first
course of brick.
Those are rock hard and solid but the numpty back in the 70's leveled them
off with what looks like a 1:10 mix (really - it crumbles to sand between
fingers).
The rest of the floor screed in both the garage area and the old original
room seems rock hard and stable enough. Going to core drill a sample to see
what the DPM looks like (probably a bit of bitumen under the screed judging
by the other floors).
The other interesting fact is that with the crap knocked off, the floor
isn't much out of level *over all*. The bay which seem high is actually at
the same height as the hall the other end of the room.
The core problem is that the covered over centre wall is high and there are
two dips in each half of the room.
I do believe that I can make this level, completely, afterall.
So all I need is a suitable compound and preparation method.
I spoke to F Ball, RWI, BAL and a distributor in Maidstone called SIG.
We are all agreed that I should scarify the asphaltic crap to expose 75% of
screed (and obviously take out the sandy bits over the old wall).
After lots of interesting discussions, the first suggestion was to use RIW
Toughseal followed by one of BALs levellers.
Unfortunately, Toughseal, which is a 2 part epoxy, costs 586 for 20
litres(!).
So, moving on... SIG suggested that some customers had reported success on
difficult floors with either Everbuild 710 or 708 levellers. Reading teh
data sheets, both can be used in cases of rising damp if the area is
treated with "Everprufe liquid DPM" first. Ironically, this *may*
be "Blackjack 908 DPM" but I need to call them to confirm it, in which case
I expect sand blinding to be involved.
So the upshot is, I reckon I can get a flat level floor with a lot less
compound and may have found a system that is stated to work with my
problems. We'll see what their technical bloke says tomorrow.
---
Sigh - another job I should not have contracted out. I had a go at the
builder about this too (I would have forgiven him - it is a difficult
floor, but his shoddy blockwork wound me up). Long and short:
1) Don't stick levelling compound onto asphalt unless the system says you
can
2) Sound out the floor and make sure it's solid (90% is).
3) Don't claim to be using Latex when the git at TP sold you OPC/silica
which seems to be good for nothing in particular.
4) Survey the floor and plan, find the actual problem spots rather than just
sloshing useless brittle crap randomly onto an unprepared surface,
especially when your customer stated the surface was unprepared and would
have happily paid for a scarifier and an extra 1/2 days labour.
If Everbuild is the way to go, it's going to be 70 quid for a scarifier hire
for a day, about 200-250 for materials (plus DPM) and some reasonable care,
and planning to apply the compound to where it's needed most.
I don't agree that the screed needs to come up - it's absolutely rock hard,
provided any damp issues can be dealt with from the top side.
Oh well, if I have a scarifier, I'll take the chance to rip off the rubbery
tile adhesive in a couple of other rooms too for good measure...
Cheers
Tim
Interesting - I'm surprised they weren't more bold, given you describe
it as a brittle layer rather than sticky.
I don't know how the price compares, but Ardex have a primer called
P-82 which seems to be recommended for bitumen, as do Weber with
PR-301. But with sandy areas...
What's going over the top of this lot?