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Does anyone know of any tried and trusted techniques for speeding up drying of a basic concrete screed? Here's the context: I have a tanked basement with a Delta pumping system. A base screed has been placed over the floor membrane with the insulation, underfloor heating and top screed still to be done. We've got a temporary pump operating as the electrics have not yet been connected. Up to end of December the screed was drying out nicely although certain areas were concerning me and potentially indicated that the membrane might have some small leaks that needed to be addressed. The contractor was due to look at these after Christmas, but on Boxing Day, the pump faulted and we had a flood - back to square one and the contractor wasn't able to identify any leak areas as the whole of the screed was no damp. We dried it as much as we could and a month later were due to get the contractor back. Two days before they were due to come, a builder switched the pump off overnight in error and the basement flooded again. We've wet vacced it out, but I understand it takes around a month per inch of screed for it to fully dry so it's still pretty damp. We've since had the contractor in again to look at some wall issues and he suggested heating the basement to help dry it out. I've tried using a diesel heater, but it's very localised heat (the basement is roughly 9m x 6m) and doesn't appear to make a huge amount of difference. Smaller but electric powered heaters might cover the area better, but until we get the electric supply in, the power needed is going to be too great for the existing power extensions. That won't happen for another week or so. Also, there is going to be an air ventilation system based on a Mitsubishi Lossnay, but that won't be in action for some time yet. I'm wondering whether there are any ways to draw the water out of the screed, such as sawdust, skim plater, paper etc, that I can speed up the process with as we're now two months behind with it. Any thoughts/experiences/suggestions gratefully received. Thanks!

I will be tiling the floor of a conservatory and need some advice on how to proceed. The conservatory is new-build with a cement-based screed. No underfloor heating. Size 5.8 by 3.8 metres 600 x 300 porcelain tiles; 0.9mm thick. Flexible adhesive will be used. I would appreciate guidance on the following: Does this size and environment need an expansion joint? Is this environment suitable for tiling direct to the screed, or do I need decoupling mat? (I have received conflicting advice from tile shops: one saying mat is required, the other saying it is not required). How long do I need to allow the screed to dry before tiling? Should I use a 10mm half-round notched trowel for this, or would another profile do a better job? I have been advised to leave a 5mm gap between tiles and walls, with silicone across doorways (where there will be no skirting board). Does this sound reasonable? Anything else that your experience suggests I should consider/do (and my lack of experience means I haven't thought of)? The screed has not yet been laid, and the builder says depth can be set so that the tiled surface will end up level with the carpeted surface in the next room (so I need to know what I will be putting under the tiles ?).

Our liquid floor screed is drying off: all windows and doors open all day - this weather is helping a lot I'm sure. Someone on BH suggested we put a sheet of plastic on the floor to see if there was any evaporation: a quick , dirty check. So I have done. When I remove the plastic sheet, the area covered by it is significantly lighter in colour than the area which has not been covered. Why would that be so? Instinct says the opposite might be the case (because there will have been less transpiration / evaporation). Anyone know why , first thing in the morning the screed is a lighter colour under the sheet than everywhere else?