Matthew Wolf is a fifth generation successor to his family’s building materials business, Henry Frerk Sons. “Every generation has run the company since it began – my mother is a Frerk,” provides Wolf. “My Great Great Grandfather started the business as a general store in the early 1870’s.”
Great Great Grandpa Henry expanded to the company’s current location on Belmont, he began the transition to building materials. His sons amassed great wealth (and then lost almost everything during the Great Depression) with coal. Matt’s grandfather brought in the first concrete trucks, and his dad developed special concrete – the type that “general cement contractors can’t provide on their trucks.”
Wolf says it looks like “his thing” is going to be restoration. “Every generation put their own mark on the company. It’s very important to me to do the same. This is also such a good point about business – you can’t stay stagnant!”
Matt first went to school for architecture and graduated with a business management degree. He became passionate about preservation during this time, learning about wood restoration, how to assess old buildings, testing masonry, painting, wall paper, etc. (He also says the Art Institute has some of the best classes available for people interested in learning more about preservation.) Since then Wolf has become an expert on restorative materials leading the company into a new era of education on the subject for their customers. One of his most passionate topics is the importance of lime mortar applications for restoration projects.
“Lime mortar has been used in America since the settlers. Portland cement (what we use today) was first developed in England in the 1870’s, but wasn’t widely used in the U.S. until the 1930’s, because it was very expensive to produce and there were few manufacturers around making it.”
Referring to actual documents at his office, Matt further illustrated his point. “For example, a rail car filled with lime, about 150 barrels worth, cost $52.50 in 1908. That same amount of cement cost $214.50 at the time – just about four times as much! Lime mortar was cheap, and you could get it anywhere. Contractors were hesitant to use cement in the beginning because it was so expensive, but when the price came down enough for contractors to use it laying brick, cement took the market over by the 1940’s.”
Cement v. Mortar
One of the biggest differences between cement and lime mortar is that cement gets very hard very fast, and lime mortar takes a very long time to set.
There are 7 different types of mortar differentiated by their hydraulic properties – the degree to which lime works with water to grow crystals and get hard. The more hydraulic mortar is, the harder and faster it gets hard.
Lime putty has zero hydraulic properties, “…it’s like sour cream”. On the opposite side of the spectrum is Portland cement; it’s made from the same rocks, but with different additives. In between the two are:
NHL – Natural Hydraulic Lime 2.0, 3.5 and 5.0 rated from weakest to strongest
Pozzolain Lime – Developed by the Romans
Natural Cement – Developed in New York and used to build the Erie Canal, lighthouses, and other structures.
Wolf says the Romans were really the first to develop lime. It was tried and true for centuries, “…but Portland cement did such a great job of advertising we forgot about lime mortar. Portland is for resurfacing and isn’t necessarily the way to go with restoration.”
Matt is committed to the belief if a building was built with lime mortar, it should be rebuilt with lime mortar. “With restoration, lime mortar breathes better – but you don’t want it to go through the brick. If you have an 1840’s lime joint and you repoint with cement mortar, it could be harder than the original mortar and brick. When mortar joints are stronger, age and the elements could damage the brick. This is because moisture gets trapped and breaks down if you use cement mortar.
Pre-1930 commercial buildings usually have this problem. You can test for the original mortar, but it’s very expensive; for residential structures, you can usually tell by looking at it. You can use lime mortar to repair later built houses too.”
Wolf is glad to see lime mortar is being widely recognized in preservations now and offers that, contractors, in general, are reluctant to use it because “they grew up with cement.” He appreciates that Fortune Restoration has been working closely with his company to learn the art of lime mortar. “I’m excited about working with them because their technical skills are so great. They are covering the walls with burlap, hand chiseling and performing other like tasks to maintain ‘proper historic masonry renovation’.”
In an effort to defray the expense of maintaining historic building applications with integrity, Frerk is the first building supplier to make a “bulk silo” for lime mortar to help bring down the cost. “We often see more damage with bad re-pointing because the wrong stuff was used. It really should be a do-it-right-or-don’t-do-it-at-all undertaking.”
The company’s general philosophy for historic buildings is to find out what the problem is first and then determine the right way to fix it. “We go to the jobsites, work with the contractors and consult to find best answers. We also realized we needed to be better educated about lime mortar and bring it to the masons. I want to network with preservationists and do more things like that.”