Moisture Meter - Test Floor Screed Moisture Before Tiling

[DHTiling]

check with british standards it's the only test they will back up

I suggest you do check lol lol.

 

[Thespanishtiler]

so what test should be applied to satisfy the bsi ?

I would be very interested to know please

 

[Ajax123]

THe British standards recommend exclusively the hair hygrometer. This is covered in annex a of bs8204:1:2003 and is referenced in several other standards. When we talk about British standards though we are talking about a guide to best practice. British standards don't "back up" anything. In fact there are areas of the industry which do not have a British standard associated with them at all. People place far too much reliance on British Standards especially when you consider that there are several elements to a floor which are covered in differing standards each in conflict with the others. British standards have no legislative or contractual authority in themselves. If you don't follow them they can't take you o court an due you.

Just because a test is not covered by a British standard does not make it an invalid test. You can measure the moisture in a concrete slab in several ways including a carbide bomb, an oven dried sample, an electronic resistivitity meter, hygro hoods, and several others.

A method simply has to yield accurate and repeatable results in order to be useable. Some of these non British standard methods are covered in other standard documents eg bba certification, European standards, ASTM standards, CSM standards, technical guidance documents and manufacturers standard methods etc etc etc....

 

[Thespanishtiler]

Thank you Ajax123

for a tiler which piece of measuring equipment would you recommend for use on both concrete and gypsum based floors ?

Rob

 

[TT Tiling]

hi i have a £35 one ,not sure wot make ,but all i can say is that we had a guy turn up and do a test for us useing one that cost £2500 and it give the same reading my one did ,lol

 

[Gazzer]

hi i have a £35 one ,not sure wot make ,but all i can say is that we had a guy turn up and do a test for us useing one that cost £2500 and it give the same reading my one did ,lol

On what substrate though ?

 

[TT Tiling]

On what substrate though ?[/QUOTE
concrete floor

 

[Thespanishtiler]

only interested in ajax123's opinion thanks, sick of all the conflicting opinions on gyp floors.

I have a meter

 

[Ajax123]

I personally use two methods predominantly. The first is the tramex moisture encounter meter which works on both concrete and gypsum screed. About £500 worth so not something i would expect most tilers to have. The problem with this on gyp floors is that it can be misleading so you need o have a bit of experiencewith the floors so you can interpret the results. For this reason I always back up a result with an analogue surface hair hygrometer which is freshly calibrated after each use. I trust this method 100%. If the Tramex says its wet then I dont bother with the hygrometer as it is pointless. You can use digital hygrometers which ou can buy for about £80 but these work differently an can be prone to innaccuracy when outside the range about 70 to 85% so if ou get a reading of above 85% you can say its not dry but you can't accurately say by how much. The accurate range is fine though cos it spans the readings we want I.e. 75% and below for cement addy and 85% and below for gypsum addy.

Occasionally I will break out a sample or laboratory analysis and very occasionally use the polythene bag test as an indicator

 

[Dan]

Bumping this one. It might be handy.