Drying screed... natural or otherwise

Noviceman

Hi Folks,

I've seen some posts re drying out screed and getting humidifiers, but i just wanted to get your opinion on my situation. My 75 mm screed is down now 3 weeks this Friday and there isn't a lot of drying this weather, i was thinking of getting a dehumidifier next week to speed up the drying process, heat is also ready to go on (not UFH), just waiting for it to dry a bit first, i'd like to get my tiles down this side of Xmas and wooden floor just after, no skirting or architraves done yet, not in a mad rush but would like to help the drying process, what do people think?

p.s. where can you pick up cheap dehumidifiers?

sinnerboy

1mm per day rule of thumb is a good guide . So you have dried out about 1/3rd now . Gradaulay bringing on the UFH over 7 days will accelereate . Don't hire dehumdifiers . Hire a concerte sepecific moisiture meter - it has tiny litle "football boot" like studs - not the pronged timber type . Wait till you get a 4% reading .
My 2p worth

muffler

In my experience i would let nature do most of the drying where possible. Keep you windows and doors open (if its safe to do so). When you get the heating going keep it at a reasonably low setting and again leave the windows open a little to allow the passage of fresh air.

After a few days of that you could bring in a couple of dehumidifiers which you should keep at low setting - primarily to deal with the moist air but also to help slightly with removing residual moisture from the floors. Dont use them unless you have to and as I said keep them low.

You should be able to hire a couple from some of the local hardware/garden hire joints

De_man

muffler wrote: »

After a few days of that you could bring in a couple of dehumidifiers which you should keep at low setting....

You should be able to hire a couple from some of the local hardware/garden hire joints

argos stock them prices start at 80yoyo

Builderfromhell

A few points to, perhaps, consider,
- I reckon this cold dry weather has been very good for drying out buildings. After all a dehumidifier works by drying the air by extracting heat ( I think).
- Dehumidifiers need a lot of time to work and the building must be sealed - otherwise your drying out the outside air, which isn't going to help.
- a dehumidifier can over do things and cause existing joinery to warp - doors etc.
- I'd leave the floor to dry naturally with as much cross ventilation as possible. Turn heating on low.
- Don't put down Timber floors over concrete until Screed completely dryed out, that is not just dry on first few millimetres.

I'd be surprised if floor isn't dry after Christmas.
Good luck
Joe

10-10-20

Builderfromhell wrote: »

- I reckon this cold dry weather has been very good for drying out buildings. After all a dehumidifier works by drying the air by extracting heat ( I think).

Just a pointer here - they use a cooling coil to collect moisture just like a fridge, but keeping this coil cold creates heat in the condenser, so on average the temperature is raised in the room slightly by the dehumidifier. Some increase the air pulled past the cooling and heating coil by a whole 2 degrees on average!

Noviceman

thanks folks, kinda what i was thinking myself, i might get the heat on this sat and turn it on low, then leave for a few weeks and bring in some of the dehumifiers when most of the drying is done... i wish it was just cold dry weather as someone suggested, but where i am, it's raining a lot..

as for 4%, i want to have it at 3% before wooden floors go in anyway, 3.5 for tiles maybe...

Dizzyblonde

We're in our last week of building now and our builders put in 2 dehumidifiers for a few weeks, they worked a treat - they checked the humidity during this time with a meter. They hired the dehumidifiers, which might be cheaper than buying them.