By Anthony Varriano
Ranger-Review Staff Writer
Kip Braden’s home on River Avenue is 106 years old, but it’s getting new legs due to a “concrete cancer.”
Braden said his upstairs, interior walls had cracked in the past due to his foundation shifting. The culprit was what looks like a concrete rash. Behind his basement walls, Braden found swelling gels of calcium silicate hydrate that forms on concrete as a result of a reaction between the highly alkaline cement paste and reactive non-crystalline silica found in many common aggregates.
“Most people don’t look behind their walls, but they should,” Braden said.
Given enough moisture, the alkali-silica reaction can cause serious cracking in concrete, resulting in critical structural damage. There is no treatment for the reaction.
Braden followed the lead of Steve Schmitz, who replaced his entire basement last summer for the same reason. His home borders River Avenue and is 99 years old.
“The biggest problem with a lot of these homes out here is when it thaws and all the water comes down from Makoshika … There are several creeks around here and the water table comes up,” Schmitz said.
Schmitz and Braden called in Lee Dykstra, operations manager and part owner of Mr. Lifter out of Bozeman, who uses a unique process to “lift” the house in order to take out the concrete foundation and replace it with a new foundation more resistant to the cancer.
“We don’t really lift it. We just maintain the height,” Dykstra explained. “This one, like Steve’s, I’ll do in two sections so you can stay living in it. It’s a huge benefit to the customer because that way you don’t have to move all your stuff out and find another place to live for a month or two.”
Once the structure is properly supported by bottle jacks and beams, Dykstra starts excavating the home’s foundation one half at a time. Once half of the foundation is removed, Dykstra starts installing styrofoam, Reddi-form blocks that “stack together like Legos.” Inside each block, rebar is run and concrete is poured around it to not only provide a stronger wall more resistant to alkali-silica damage, but a better insulated wall as well.
“I was one of the first to use the Styrofoam blocks 15 years ago,” Dykstra said. “The rebar makes it strong so it can’t move.”
The nice thing about the Styrofoam blocks is that they come with strips that can be screwed directly to drywall, and they also make it easy to cut in ducting and electrical, Dykstra said.
Once half of the foundation is poured, a week of curing is required before starting the second half, which is when Dykstra prepares his next job. Then he comes back to complete the second half of the foundation. After that, a waterproof membrane can be installed to further minimize the chance of the alkali-silica reaction causing future damage. Schmitz installed brick around his foundation, and some homeowners choose to cover the outside of the foundation with stucco.
Braden said Dykstra started work on Oct. 3 and expects to be done by Thanksgiving. Dykstra said he likes to complete a basement in two months, but, of course, that’s dependent upon the size and condition of the house’s basement.
Dykstra estimated his cost per square foot to be around $62 in Braden’s situation, but again, said it varies based on the condition of the foundation and how much material and labor is needed. Existing basements can also be expanded using the same technique. Dykstra said he can basically “lift and level anything.”
Dykstra said “there’s no shortage of work,” and he has another job already lined up. He expects work to continue to be available in this area. For more information about the process, visit MrLifters.com.
Reach Anthony Varriano at rrsports@rangerreview.com.