We hired Thiesse to remedy a problem in our basement that was being caused by the city sewers backing up during heavy storms. They recommended installing an ejector pit, into which all the basement piping (floor drain, laundry tub, etc.) would be plumbed. This in turn would eliminate the open drains that the city sewer was backing up into.
After they did the work, we noticed backups in the main stack & immediately notified the company of the problem. They came out again & spent a couple hours rodding the sewer line immediately outside the area they'd worked on days earlier, then told us they couldn't find anything wrong but we should break open the main sewer outside the house, as it was likely blocked or collapsed. (Huh?) We declined this, since we had never had a problem with it prior to the work they did in the basement. We paid almost $500 for this rodding & diagnosis, by the way - this was in addition to the money we paid to have the ejector pit installed.
About a week later, I went into the basement & noticed another backup around the floor drain & water again leaking out of the joints in the main stack a few feet above the floor. This led me to believe the blockage was inside the house. My wife called Thiesse & asked they come out yet again to fix the problem.
When they arrived, they brought their sewer foreman with them - someone who had never seen the house or the work previously done. He proceeded to try to rod the line inside the house, but kept hitting an obstruction beneath the floor. He broke the floor open (this after we had already had it patched after their previous efforts) & determined the plumbers who'd installed the ejector pit had inadvertently filled the main line leading outside with hydraulic cement. His words were looks like we caused the problem.
They returned the next day & removed the clogged pipe, breaking out even more of the concrete floor in the process. Sewage finally flowed again, but Thiesse had the audacity to send us another bill for fixing the problem they had created! We told them in no uncertain terms we would not be paying the bill & they became very hostile, claiming WE had somehow caused the problem.
Our experience was among the worst I've ever had with a company & I would never, under any circumstances, recommend them. Buyer beware.