Jeffrey Matthews
Why do stone problems occur? There are many reasons! Many times it is because the stone is not selected correctly for the use for it is intended. The stone then fails because of cracks, holes, staining, improper thickness, improper blending or understanding of the stone“s range in color, improper size, lack of suitability for exteriors, lack of the abrasive resistance required for such a floor, or the high absorption of the stone.
Perhaps the problem occurs due to improper installation. It should not have been made so thin; or it should have been set with white cement instead of grey, or epoxy rather the portland cement; or the anchorage system was not sufficient; or weep holes were not allowed; or oil-based products stained the stone. There are a hundred reasons why stone installations fail.
Finishing and maintaining stone is just as important factor as all the above. If the stone was polished and is showing wear, you will have problems. If the stone is highly absorptive and a sealer should have been used and wasn“t, then a failure will occur. Perhaps the foot traffic is too heavy for the area, and it might have helped to have a sealer; or perhaps the stone is in a wet area where water and rust penetrate it. Sometimes the sun will discolour the stone, or oxidation occurs due to metallic content in the stone.
Many times stone is fractured and has open seams. The stone is set with coloured epoxy grout, which gets into the seams, and voilą, a problem occur. Who is at fault? What should have been done? What can we all do?
Education is most important. There are very few stone experts, and even fewer salesman who know stone. Architects demand knowledgeable stone people to call on them an assist them in avoiding all the above problems. Perhaps the stone they require for the job must withstand high traffic, or have high tensile strength, better density and absorption, or flexural strength.
Let me outline what typically happens in buying or specifying stone. The architect / designer has a job. He or she finds, in the local area, a distributor who demonstrates some knowledge of stone. So he requests that a salesman visit him. This salesman comes in with all sorts of granites, marbles, slates, limestones, etc.; the architect / designer is impressed with the available selections. Or perhaps no salesman calls, and the architect / designer just sees the stone in question on another building, or has a catalog and sample kit sent over. Whatever method is used, the specifies narrows down the range of options to stones which are pleasing to the eye and of a colour that superficially suits his or her needs. The supplier / distributor is advised about the selection (though sometimes not), and samples are then requested. Wow - the architect / designer received 6" square samples, and he or she is really lucky, a whole 12" x 12" sample. The name of the stone is "Harry“s Red".
What a nice name! The architect / designer asks for testing and other information - of which, of course, either none is available, or else that which is supplied is five years old, and does not come from the quarry as the sample.
"We want polished marble tiles on the floor", says the architect. "OK, no problem", says the supplier, "We make it 12" x 12" x 3/8".
Seven months later, the job comes out for bid. The specs read: "Harry“s Red by XYZ supplier in 12" x 12" x 3/8" polished tiles". The contractors, get the drawings and find they need 25,000 square feet. They have one week to bid the job - three days only, after the take off is done. The contractors start calling around to locate the stone, and perhaps call the XYZ supplier, as specified. When XYZ supplier gets the call, he says: "Oh, really? I didn“t know it was out for bid. How much stone is involved and when do you want the bid?".
"Tomorrow", answer the contractor, as he goes and calls all his other friends and suppliers domestic or foreigners to locate a cheaper source. The contractor gives the price and / or alternate. What does it mean "specified stone"? Most general contractors, especially in New York , state: "We do not give out specified suppliers“ names, and we always allows alternates". The cheapest supplier / contractor general / constractor, etc is awarded the job. The job is installed with Tim“s Red, since it turns out to be cheaper and close in colour to Harry“s Red.
Now, what is wrong with this scenario? This has happened to hundreds of people, every day, throughout the world. Stone problems occur; we are all at fault for various reasons. We need to change our way of buying, selling, bidding and controlling stone.
The two key words I will propose to you in this article - and I hope you remember them - are knowledge and control.
KNOWLEDGE
All parties entering into an agreement to supply or use stone must be knowledgeable about what they are doing, buying and using. We should require the following:
1.- Proper naming of stone.
2.- Proper testing of the stone to make sure it is sufficient to past the tests required for its use.
3.- Knowledge of the recommended application for the stone, and indications of where it has been used before successfully.
4.- Knowledge of the quarry, to better understand whether there is only one quarry handling this material or many. If so, how do we select the right quarry for the selection we are making? How does the stone change in testing form inside various areas of the quarry to other quarries?
5.- Stone colour variation. How many samples of 12" x 12" are needed to understand this stone? Why not supply pictures of slabs and the quarry to show this as well?
6.- How does the rift in the quarry affect the stone? How do we specify the quarry name and location within the quarry? Is the stone cut with or against the bed?
7.- Can we specify or offer blended material from contiguous blocks?
8.- What thickness will we recommend?
9.- Is the stone available in the quantity needed to complete this job in a timely fashion? This is always a problem.
10.- What finish are we going to recommend? The architect wants polished, but we know it is intended for floors. And the MIA (Marble Institute of America) does not recommend polish for floors. What shall we do? (Give the architect what he wants, I guess?).
11.- Can we suggest budgets for this job in advance to enable us to know whether it is even affordable by the owner and general contractor for this job? We should all ask for preliminary details about the job in order to know more and check them out in advance.
12.- Give installation recommendations for each area of the job.
13.- Most importantly, know the stone well enough to recommend maintenance procedures at the time of specification.
14.- More information on the supplier from whom the stone will be bought.
15.- More information about the stone. The more you know about the stone, the better. If you can not acquire substantial information about the stone, do not use it.
CONTROL
We all need control on this job if it is to be successful. Control starts with the distributor / supplier, is supposed to be enforced by the architect / designer, and is then to be adhered to by the general contractor and stone supplier. Who establishes and implements this control?
We all do. It is the job of everyone to better know the stone and the controls required to give the owner what he expects. Some of the things that should occur to us or should we have are as follows:
1.- Proper samples to show colour range in the beginning, and extra sets of these maintained by the suppliers to control it during production.
2.- Better specifications to support the suppliers who have helped you set up these controls, and who have proved that they can control the stone.
3.- Proper testing of stone before and during the job.
4.- Knowledgeable stone contractors who know the problems with the specific stone in question and the installation method that must be used to assure quality and problem free maintenance.
5.- Purchase orders that clearly state the stone name, date required, quantity, specifications for quality control, testing requirements and performances, colour control per samples, price, labour items and tolerances, shipping and packing instructions, penalties for late delivery, improper fabrication or variance with the details specified. You should be amazed at how many purchase orders I see that say nothing more that "Ship 25,000 square feet of White Carrara 12" x 12" x 3/8" tiles, polished". What does this mean? How much control are we going to have? What is "White Carrara"?
6.- Controls on shipping and expediting to the job; assistance on unloading and storage at the job; instructions on storage and movement to the work area and how to protect the stone from other trades“s walking over the new stone area just installed.
7.- Careful watch on the installation method being used, including how the stone is sorted and selectively installed at the job, and the grouting and cleaning of the finished worked area prior to signing it off to the owner.
8.- A maintenance brochure or instructions on how to take care of this beautiful job, and what to look out for and what to do when a problem occurs.
9.- One of the most important controls is not to always give the job to the cheapest bidder. We need to award jobs to the most competent, the most informative, the most supportive; there are enough such people to supply us with competitive bids.
10.- And finally, we need to control alternates. If the architect / designer has not done his / her homework before the bid date to allow alternates, then none should be allowed. The architect must control the general contractor and what he or she is allowed to do in order to control this job and the design as originally intended. To give you an example, the Coca-Cola building in Atlanta has a beautiful atrium with a design-patterned floor. It was recommended to them not to use Negro Marquina, and further, if they did use it, to test and select a proper sealer to protect it. They used Negro Marquina, and the job was specified to have a sealer, but not sealer was used. The open house came, and they served Coke and champagne. What a combination! Of course, we all know what happened: the floor lost its shine quickly. The next day the architect was on the phone to find out what he was to do - knowing full well what he already knew and should have done. The stone industry requires all parties to be knowledgeable and exercise control. If the industry is to have progress then we must be more aware of what we are doing. With the increasingly advent of new countries getting into the market, it becomes more important to set buying and specifying guidelines. Any country can by the technology and machinery required to produce dimension stone, even though they may not have the background in making it or supplying it in the world market. It is up to all of us to take better care with these new suppliers, and to pass on to them our knowledge of the needs of the market and the quality control that are required. It is a shame to have failures occur over and over again for the same reasons: it shows lack of unity and lack of control.
We are supposed to be creatures with brains, who study history and learn from our past mistakes in order to make the future better for our children. Why not carry this philosophy into the stone business and work together to make it a better industry? We will all benefit. Let“s not treat natural stone like a man-made ceramic. Let“s appreciate the natural beauty of this product, learn to control it in our favour, use it wisely, and have it last for years to come. With knowledge and control, we can do this.
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