Anhydrite moisture testing, putting some ideas to you Trusted People

[bugs183]

Hiya me again, and guess what it's Anydrite again, but i'm hoping something positive.
As we all know i've been asking lots of people lots of questions on all aspects of this flooring to try and get some kinda satisfactory answers and systems in place for us all.

Now, a question to you all, be honest, i'm just brainstorming at the mo.
We all know that apart from the adhesive issues, that another issue is moisture testing.

SirAmic and I have been doing battle with a F Ball hood Hygrometer, and after probing more people these boys didn't get much of a thumbs up.

This is a British Standard method of testing the floors as is the Carbide Bomb test. Many surveyers (mainly abroad) favour the method where a probe is drilled into the floor (there are ways of voiding underfloor heating pipes), and the moisture content of the screed itself is measured, this is not BS standard for tiles but was passed for wood last year, so it may become a standard for tiles too.
So if a third party was available to go into a clients house/project and conduct a moisture test using the above methods plus a more general method that would test the floor as a larger area, would you guys be interested in this?????
If a survey could be done on an average floor in about an hour and included a Carbide Bomb test to meet BS what would you think either you or the customer should pay for such a service? Bearing in mind i've heard talk of a guy charging £1000 for a Carbide Bomb test!!!!
The longer tests such as the 'Hood' Test and the in situ probes obviously would be carried out over a series of days, but would give more accurate results. What do you think would be a fair price for these??

 

[Gazzer]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

i was told the carbide bomb test was around the £300 mark.

 

[bugs183]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

I've heard £300's about the average cost for that test.
If you added up the hours faff you've had chasing the hygrometer for readings, what do you think its cost you???

 

[The D]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

I’m not going to pay zip and I would be pizzed as a consumer to have to pay £300.00 to find out if my floor is dry.

 

[bugs183]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

It's a very good point Deano, but there is no other way of knowing if these floors are dry without testing.
As tilers we've got away with not testing concrete screeds for years, but these aint going away and if they are too wet then they will fail.
And that could cost loads more than some tests.
THe trouble is you could pay £300 and find it isn't dry, then you have to get the floor tested again at a later date.

 

[bugs183]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

Do you all think it's the screeders job to sand and test the floor???

 

[John Benton]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

Do you all think it's the screeders job to sand and test the floor???

Thats a good question Bugs. Does the joiner sand all the woodwork before the decorator paints?

 

[The D]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

I have no problem with sanding the floors but I do not want the responsibilaty of of testing the floor or recommending the system and products to compleat a guaranteed installation.

 

[Pebbs]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

For me, yes I would pay, or rather make it a pre-lim in my contract that the substrate is tested before the works can commence. So for commercial contracts this is the way forward as far as I am concerned. I don't want the responsibility of testing it, we have enough to do already. So yes get someone in to do the tests and give the ok or not as the case may be.

Lynn

 

[Gazzer]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

Thats a good question Bugs. Does the joiner sand all the woodwork before the decorator paints?

Does the painter do the grouting ?

 

[Andy Allen]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

cant see a private punter being happy to pay anyone to say his floors dry, unless this is all sorted before he agrees to have the screed installed..

ive not had much to do with these screeds, but everyone of them ive looked at, the customer has only ever been told you can tile it after x amount of weeks, no mention of bomb test or hygrometers....

 

[John Benton]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

Does the painter do the grouting ?

I was just throwing that in the mix to see who people think are responsible for preparation. Where does one trade stop and the next one start?

 

[bugs183]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

All good points everyone.
So by the generall feel so far you believe that is down to the builder or the screeder to take the responcibility of saying its ok to tile on.
Andy, this is the very problem that is happening people are being told these are fast track floors when it is not the case at all.
Now is this the screeder not telling the customer the facts or is this the screed manufacturer not telling them the facts?
Keep your views coming everyone as i'm interested in anything to do with these screeds as it's of benefit for all of us.

 

[DHTiling]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

The biggest issue IMHO is the ones selling these screeds, they push the benefits of installation speeds and the neutron strength over traditional screeds but why oh why do they not say they are slow drying and if UFH is installed they yes they can be force dried but this creates megga issues with shrinkage to joists and door casings etc etc.. the last 2 floors that i have had force dried, the builder and customer have said they were not happy about timber walls up stairs etc etc all twisting as the heat from force drying is unreal.

My question is this : If a green cement based screed can be tiled with say a vapour equalisation membrane like Ditra and why can't an Anhydrite screed be done the same way with a gypsum based adhesive ( no reaction with sulphates) , so Ditra stuck down with gypsum based adhesive and then the vapour is taken away within the mat as normal and then tile on top with your normal adhesive you use..

Gypsum to gypsum does not react, so why can't it be done that way..?

After all the 2 gypsum products can cure under the mat.

Answers welcome.

 

[Ajax123]

Re: Anhydrite moisture testing, putting some ideas to you Trusted Peop

I beleive that itis the main contractors responsibility to test the floor to make sure it is dry. In bs8203 which covers resilient flooring this is covered. However in bs5385 it is not. This leaves it open for contractual debate. The most it needs to cost is 80quid or thereabouts for a hygrometer. Most larger contracts or decent sized builds will absorb this sort of cost easily and frequently do. I am seeing more small builders taking up this option as well. I beleive it is then the tilers responsibility to carry out any necessary preparation prior to tiling I.e. sanding, vacuuming priming etc.

if this could be laid out in stone tablets then things wold be easy but unfortunately it is not and allow these things can be contracted by anyone. However it needs to be noted that in order to accept a contract a contractor should be able to demonstrate the necessary expertise to fulfil said contract. In other words if you don't know how to do a job dont do it.