Discussion
You might be able to get a Tarp over it.
All that happens is that the surface goes dusty when dry. If you've got/need a nice surface finish, it's probably a disaster already.
It will weaken the surface to some extent, but not the whole. If you're going to put bricks on it you'll probably need to clean the loose stuff off first.
IIRC concrete sets underwater.
All that happens is that the surface goes dusty when dry. If you've got/need a nice surface finish, it's probably a disaster already.
It will weaken the surface to some extent, but not the whole. If you're going to put bricks on it you'll probably need to clean the loose stuff off first.
IIRC concrete sets underwater.
dilbert said:
You might be able to get a Tarp over it.
It will weaken the surface to some extent, but not the whole. If you're going to put bricks on it you'll probably need to clean the loose stuff off first.
IIRC concrete sets underwater.
Correct, but you need special concrete to set underwater.
The rain will weaken the surface, so get it covered. Plus the rain may leave marks in the surface. If it's just for walking on it'll be ok, but get it covered if possible.
Robbie (doing Civil Eng degree)
Balmoral Green said:
That's OK, i'm sure you wont be able to help me another time.
you know what, it's just come to me.
I once left a bucket of wet concrete in a full bath while I answered the phone in the mistaken belief that it would still be liquefied when I got back....
...it wasn't, and I had to chip it off the bath (fortunately it was cast iron) with a lump hammer and sizeable chisel. so, I can answer with a small degree of authority that you should be ok although I would imagine that the surface won't be as smooth as it could be
Balmoral Green said:
Thanks for the feedback folks, it doesnt need to be a good surface as it will be tiled. My main concern is that with it sitting on a damp proof membrane which also goes up the sides, it isnt draining, its filling up.
I see what you mean. I've no experience of that scenario, but I'd think there was enough weight there to keep the water out.
The membrane must have been a flat sheet, I would have thought that the water could drain at the corners?
I really wish I had gone to a few more lectures rather than going to the snooker hall. 
Hold on:
Lecture = boring fart going on for hours about shite.
Snooker hall = toasted cheese and mushroom sandwiches, booze and snooker.
RobbieM sounds very knowledgeable.
Personally, I would not worry too much, but if it rains a lot, the tanking/ponding effect would cause concern.*
*The company that I work for will sort it for you on dayworks (sharp intake of breath, rubs hands).
Hold on:
Lecture = boring fart going on for hours about shite.
Snooker hall = toasted cheese and mushroom sandwiches, booze and snooker.
RobbieM sounds very knowledgeable.
Personally, I would not worry too much, but if it rains a lot, the tanking/ponding effect would cause concern.*
*The company that I work for will sort it for you on dayworks (sharp intake of breath, rubs hands).
Balmoral Green said:
Had 16 square metres of concrete laid this afternoon on top of a damproof membrane and insulation, it is now raining hard. Is this a problem?
BG assuming the initial set has occured i.e. the surface is not washing away, then don't worry about it, the water actually helps the strength gain as it controls the hydration and stops small cracks occuring from heat build up
The insulation also shouldn't be a problem as most products suitable for underslab works are waterproof to a great extent. Just make sure the the surface is completely dry before you go tiling it though
BG is TILING the floor of the new garage he's having built for his new Bentley? Obviously too much money. 
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