what do we really know ?

[Diamond Pool Finishers]

How do we know if the building materials we are going to use on any particular job, is going to be really fit for the job, the manufactures say it is fit for this job but how do we know that this is really the case,any guy can come -up with an idea, ie system material, and say to the public this will do so & so, who says that guy is qualified,? is right ? and that the idea/material/system is right or will work,?.
we have seen some interesting materials /systems come to the front in tiling in the last few years, un-coupling systems for one ,we all go about advising peeps to use this system, but how do we know for certain that they work !! we all had a fright just a little while ago with -one particular make, ! then we are told don't worry we have fixed it ! who has checked the company! or are we just accepting what they say ?
there are gypsum screeds who is checking if all these work in the long-term, most idea's are driven from a want to make money or more money, who is checking that it actually does what it says on the packed for the end user's?
adhesive manufactures have come out with a lots of different addys for different situations ,who els checks and validates there claims ?.
just have a think before you answer, it's a bit like years ago the quacks ,made claims for there medicines ,that were only herbal remedies and not real medicines :builder2:

 

[DHTiling]

Gypsum/Anhydrite screeds have been in europe Dave probs since the 80's... It is the UK that is behind with such screeds but we are getting there lol


With the building game changing so much in even the last 10 yrs , we as fixers and adhesive comps do try to keep up with new methods.. most comps do quite stringent testing before releasing new products to the open market..


The membrane failure was down to the glue failing that laminated the 2 sections of it together.. and it was not just one named mat , it was ALL of them made in the same factory... these would be Dural/Genesis/Blanke to name some...

I do agree though, we as fixers do and suppose have to put faith in these products ... or we will be stuck in the dark ages forever.. :lol:

 

[Diamond Pool Finishers]

the gypsum screeds have come from America as they did all that back 1950-60 then is was re-jected because of the failure rate,as far as i can ascertain from the john /forum, i does worry me that they are now being pushed over here,after such a record in the states where they were under a different name

 

[Diamond Pool Finishers]

there a is the BBA british board of agreement, and BRE building research establishment, BSI british standard institute , .
but why so many ?
why don't we have one , government, standard that strictly covers the lot, or is that to much liability !

 

[Ajax123]

Gypsum screeds have been around since just after the second world war. They were first recorded in east Gearmany in 1948. Lafarge are a relatively recent entrant into the market beginning in the uk in 2000 but the technology is tried and tested. Gyvlon used to carry a BBA certificate but as these are generally for systems not covered by a national standard and maintaining a BBA cert is quite expensive the certification was lapsed in 2003.

Some of the manufacturers offer CE certification which is available as a third party acceditted warranty of minimum performance. Some manufacturers offer product warranty for specified terms. I have issued such documents myself. The screed binder should be manufactured to BS EN 13454 which offers an assurance that it is of suitable quality and meets certain criteria. The screed itself should be manufactured to a minimum of BS EN 13813 which means that the screed mortar is manufactured to certain minimum standards.

Different systems have to meet certain test criteria e.g. Fire ratings, strengths, minimm durability levels, surface abrasion tests etc etc.

It is important that when selecting any material that the manufacturer can demonstrate compliance with certain standards. That is on major advantage of many of the calcium sulphate screeds available. Additionally many of the manufacturers carry third party accreditation for quality assurance with means procedures must be in place to ensure that the standards are complied with.

Now then......tell me......what quality assurance and demonstrable methods of testing are available to ensure that traditional sand cement screeds are fit for purpose. After all they are not really that much older than gypsum screeds when you think about it. Site mixed screeds do not even comply to a British standard these days.....

I can say with absolute confidence that gypsum screeds are fit for the purpose for which they are designed. They are NOT designed for use in swimming pols though Dave so don't worry too much. You won't come across them often.

Why are there so many testing houses or certification bodies .... Well that is simple. It is a free market and anyone can set pin business to test things.

 

[DHTiling]

even more years than i thought Alan... JEEEEZ..

 

[Ajax123]

All that said I completely agree that there are untested systems in all avenues of construction. We are so far behind the rest of developed Europe though that many of these systems have been used over seas for years before they finally reach some sort of acceptance over here.

 

[Diamond Pool Finishers]

All that said I completely agree that there are untested systems in all avenues of construction. We are so far behind the rest of developed Europe though that many of these systems have been used over seas for years before they finally reach some sort of acceptance over here.

or rejection over here as well

 

[Ajax123]

Touché .....

 

[Diamond Pool Finishers]

Now then......tell me......what quality assurance and demonstrable methods of testing are available to ensure that traditional sand cement screeds are fit for purpose. After all they are not really that much older than gypsum screeds when you think about it. Site mixed screeds do not even comply to a British standard these days.

A fair point alan , and right on booth counts , we have to depend on the plant that mixes it for quality, until there is a failure then it has to get tested by a lab, and lets face it site mixing is only as good as the labourer doing it i was about right with the dates 1950 ish:yikes:
but it beats me why you would want to put gypsum in screed ( ok it's lightweight ) but it is very susceptible to moisture /water ,that is why plasterboard in no good in showers IMO as plasterboard is gypsum based ?
this thread was to get us all to ask searching questions about our materials /systems/products in general , not an attack on gypsum screeds !
as i am very concerned with the problems me my all face ( legally ) in the future if we have problems , we could end -up holding the baby !

 

[Ajax123]

Now then......tell me......what quality assurance and demonstrable methods of testing are available to ensure that traditional sand cement screeds are fit for purpose. After all they are not really that much older than gypsum screeds when you think about it. Site mixed screeds do not even comply to a British standard these days.

A fair point alan , and right on booth counts , we have to depend on the plant that mixes it for quality, until there is a failure then it has to get tested by a lab, and lets face it site mixing is only as good as the labourer doing it i was about right with the dates 1950 ish:yikes:
but it beats me why you would want to put gypsum in screed ( ok it's lightweight ) but it is very susceptible to moisture /water ,that is why plasterboard in no good in showers IMO as plasterboard is gypsum based ?
this thread was to get us all to ask searching questions about our materials /systems/products in general , not an attack on gypsum screeds !
as i am very concerned with the problems me my all face ( legally ) in the future if we have problems , we could end -up holding the baby !

When I used to sell sand Cement screeds I used to use the plaster board analogy as well. If you leave plasterboard in the rain it swells and fails. Since working with gypsum i learned the error of that particular analogy. Gypsum comes in many forms being an amorphous chrystal. The material used in plasterboard come as very large and loosely packed crystals powedered and pressed to shape. These allow the moisture to quickly affect the structure of the material.

Gypsum screeds are a different and much more technical animal ( or mineral as the case may be). They use chemical reaction in order to form a matirx rather than wet powder pressing. Anhydrite in particular form very small and tightly packed crystals which form close bonds around a matrix of sand. This chrystal arrangement helps to prevent water ingress and the integral strength developed prevents the moisture from forcing the chrystalls apart. Bare in mind that the screeds are designed for use in areas where they will remain dry so moisture should not present a problem. However it must be noted that the screeds are very robust to moisture and temporary wetting is not an issue

I thinkit is fair to say that whilst I appreciate some still have concerns about these screeds they have acheived widespread acceptance throughout the UK, Europe, Asia and the Americas..... Although perhaps not so much in he Americas due to less than national coverage. Gyvlon alone has increased its market share throughout the recession and continues to grow.

Pain terms of legalities apart from all the standards and tests in place a manufacturer/supplier still has to satisfy the provision of goods and services act and supply a material which is fit for the purpose it is intended and of merchantable quality.

I also accept your concern that some manufacturers might run for the hills but in my experience the failures associated with most materials are very rare.the failures due to incorrect, inappropriate or plain foolish applications or use are very common. Materials don't make mistakes....people do.

I do occasionally walk away from problems but not often and generally when I am confounded by a tradesmans unwillingness to accept the facts e.g. A screed which has been installed with no roof and has not dried in the 1mm per day we usually quote. I will always offer solutions but sometimes people just want someone else to blame. There is after all no point in arguing with someone who does not want the answers to the questions they ask .

 

[Diamond Pool Finishers]

some good points alan and very well explained with the Crystal arrangement ,it makes more sense now ,Bare in mind that the screeds are designed for use in areas where they will remain dry so moisture should not present a problem.,but this is obviously a worry for you guys then, you dont get this with ordinary screed !.
i do agree it's people and not the material that makes the mistakes, but at the start of my thread i did say peoples coming up with idea/products /systems.
a manufacture that was to go out and actively seek a solution to a problem is to be commended, and in all fairness would probably not be in this situation as they would have satisfied most of the criterior in the first place ,