Sealed Limestone

Impregnating Stone Sealers

The proper way to seal stone is called impregnating. This is a method which uses silicone or flouro-carbon  type resins, made soluable in liquid carriers, either water (water-based) or petro solvents; aromatic and aliphatic (solvent-based). The impregnator is applied to the stone, and soaks into the surface. The base (carrier) then vaporizes and the resins remain in the stone to cure. This method of stone sealing does not fill the pores of the stone and will allow the moisture to transmit. Moisture transmission (breathing) is very important for stone, to prevent problems such as spalling (flaking), oxidization (rusting), and efflorescence.

 

Stone Sealing

It is a matter of some debate weather all stone needs to be sealed. In most cases it does help. In some cases it does not make much difference. In a few cases it can actually be harmful to the stone. In many cases the stone absolutely needs to be sealed. It all depends on the stone which it will be applied to, if it’s a suitable type. Some stone sealers should only be applied in interior applications, and some stone sealers only used externally. For more on this you can read this excellent article on our blog: http://stonecaresolutions.blogspot.com/2011/03/bare-truth-about-stone-impregnating.html

Either way, take heed of companies who make a career out of stone sealing. Sealing is just a part of what a qualified stone restoration service provider will offer. Sometimes there are better options for the money to be spent, to provide a more necessary result for that application. Remember that most of the time stone sealing (impregnating) will provide little or no aesthetic result.

 

Enhancing Slate; Before

Colour Enhancing Impregnators

Colour enhancing impregnators are stone sealers designed to enrich the natural colours, and will provide an aesthetic result. These enhancing sealers do a wonderful job at making old and oxidized materials come back to life, or add even more character to certain stone types, like slate, sandstone, quartzite, and granite. True enhancers will not leave any surface film and will allow the stone to breathe. Some enhancers are really just solvent based acrylics. These are a cheap imitation and not a suitable option for most stone types. The drawback with enhancing impregnators is that they can sometimes fade with UV exposure. We have found that some brands are better than others, and along with the correct application methods, we can ensure the longest possible effect.

 

Enhancing Slate; After

We take great care in specifying the correct sealer for each application, to make sure you get the greatest effect and long lasting results. The products we use are of the highest quality from the best suppliers in Australia, and overseas.

Our application methods ensure the deepest possible penetration of the resin solids into the stone, often “layering” two types of sealers in a specific order, to guarantee the stone will be sealed from all types of contaminants, both water and oil borne.

Stone Coatings

Stone coatings are usually coatings that are not stone coatings at all, meaning that they are usually not produced as “stone specific.” These coatings are general purpose, that are also marketed as suitable for masonry, and sometimes stone. The coatings have solids of either acrylic, urethane, or more sophisticated blends sometimes requiring a catalyst. It is my opinion that coatings, because they will not allow the stone to breathe naturally, are not suitable for stone. Of course there are exceptions for every rule, but I cannot remember the last time I felt it was necessary to use a coating. Coatings should only have to be used when a stone is specified for use in an unsuitable environment, and maintenance will be too difficult otherwise.