QUESTIONIs limestone a suitable product for a walk in shower and the surrounding areas. We have been told that it will require more maintenance than other choices and it is hard to remove stains. Also that a professional would be needed to periodically seal it. We would appreciate any advice you can give. The remodel will cost about $20,000. Thank you
ANSWERANSWER - Limestone is commonly used in shower applications. Not all limestone are the same. There are ASTM material standards for each geological classification of natural stone that lists what the maximum or minimum physical properties are for each to be considered suitable for the building industry.
Limestone is ASTM C568. It lists limestone in three sub-classifications. Class I Limestone is a low-density limestone that can have an absorption rate between 7.5% and up to 12%. Class II Limestone is a medium-density limestone that can have an absorption rate between 3% and up to 7.5%. Class III Limestone is a high-density limestone that can have an absorption rate of up to 3%.
The less absorption that the limestone has, the less propensity it has to staining and the less maintenance required.
Limestone normally does not come polished and in a shower environment it should have a hone finish. If you seal the stone with a good quality penetrating breathable sealer and reseal about every year, it will be more stain resistant and easier to maintain. If you maintain the limestone correctly it should not stain, and if it does, most stains can be removed if they are treated timely.
A key to a successful installation of limestone is to make sure it is installed correctly. More often than not, when there is a problem with an installation it is due to a poor design or a bad installation.
Natural stone will require more maintenance and care than a ceramic tile, but consider that the limestone is literally million of years old and and a natural product. Most people don't mine if the stone acquires a patina over time. Others want to keep like new, and the beauty of natural stone is that you can always have a professional restore it by regrinding and honing it.
I know that in my two showers with natural stone that have been installed for about 10 years, they still look like new. The key is to make sure they are installed correctly.