Question from Lex
I have already purchased a marble/resin threshold that I can use for an upcoming bathroom renovation. I am having trouble getting more info about the resin from the company in Italy.
I do not have sensitivities, but am just worried about exposing my baby to toxic materials once it is born. I am not installing it and will be out of the house for two weeks when it is being installed.
Is there any reason why I should worry about the marble/resin in a threshold? I see that there are greenguard certified thresholds, but my contractor really wants to use this one.
The technical name for what you are asking about is “engineered marble.” It is different from the “cultured marble” of yesterday, which was made from the dust of various stones, in that engineered stone is made from recycled pieces of marble and stone discarded by quarries.
Using bonded marble allows a manufacturer to make a product that looks and feels like marble, with more uniformity and at much lower cost.
To make engineered marble, pieces of stone from the quarry are crushed, pressed, heated and bound together with just enough polyester resin to form slabs, which are then cut into pieces appropriate for their use. Once cut to the desired size, they are then finished with a protective coat of polyester resin.
Though polyester is typically made from petroleum, in the form of a resin it cures into a hard material that doesn’t outgas. Even if it did outgas, polyester is generally not toxic, except for those who are sensitive to petroleum.
I’m not concerned about engineered marble being a toxic material.
In this case a GREENGUARD certified threshold only means that the company paid for the certification. All engineered marble is pretty much the same.