BEDFORD — The Empire State Building, the Iowa State Capital, the national cathedral all have something in common — they were built with local Indiana limestone.
“I find that amazing,” said Todd Schnatmeyer, executive director of the Indiana Limestone Institute of America. “Out of the (stone) belt in three small counties came all these national buildings.”
But anyone who owns a home with limestone making up some part of it, or anyone walking around all the limestone buildings in Bedford, knows that the stone can wear and tear, stain and even burn away if not treated properly.
Schnatzmeyer, who spoke at the Bedford Chamber Friday about how to care for Indiana limestone, often consults and assists people and businesses that want to know about how to properly install and maintain Indiana limestone.
“We support the users of the stone starting with the architects,” Schnatzmeyer said.
A lot of the issues he brought up at Friday’s meeting included poor design. For limestone to look good, there has to be room for the rock to expand, it needs proper drainage and maintenance workers who are responsible for cleaning need to know what not to do.
Some problems are so damaging that buildings have had to be dismantled and put together again, according to Schnatzmeyer. Other problems are a lot easier to take care of, such as alkali stains. Alkali stains appear as a brown, rusty color on buff stone and a gray-brown color on gray stone, and they normally show shortly after construction. Normally, large amounts of water causes the problem.
“The stone does not like getting its feet wet, I tell people,” Schnatzmeyer said.
The most common way of removing the stain is to just remove the source of the abnormal amount of water, such as wash from concrete pours, and letting the sun and rain clean the stain over time.
Other stains can be caused by things like sealants, if the wrong sealants are used, Schnatzmeyer said. The same thing is true of mortar. He encourages anyone wanting to use limestone for a building to make sure all products are compatible first. He encourages a test run before construction on a smaller care to ensure compatibility.
Problems with limestone also arise if not treated properly. A common issue is when cities put salt treatments on sidewalks during winter. Schnatzmeyer showed a picture taken near where Subway used to be on Bedford’s square at 16th and I streets. The limestone absorbs the salt moisture causing the limestone to fret away. It can be treated with salt-removal options, Schnatzmeyer said.
Other problems, such as fungal growth, can be solved with cleaning solutions, such as using bleach and a fiber bristle brush, according to Schnatzmeyer. But he always urges precaution.
“You can resolve a lot of these problems on your own,” he said. Power washing is also a viable way to remove stains, but only if the correct settings are used, Schnatzmeyer explained.
“Be cautious and inch into it. Don’t start near an entryway,” he said.