Nobody can see whether a waterproofing job worked until the next big storm, and by then the crew is gone and the wall is closed up. That is why this trade gets oversold. Vetting one in Michigan comes down to six checks you can run yourself, starting with a license number.
1. Verify the Michigan license first
In Michigan, basement waterproofing is one of the trades covered by the state Residential Builder license required under the Michigan Occupational Code (MCL 339.2404) and administered by the Department of Licensing and Regulatory Affairs (LARA). Before you let anyone quote a job, confirm they actually hold a current license. You can look up any builder by name, company, or license number through LARA's online license search, which shows the current status, the expiration date, and any disciplinary history on file. A contractor who cannot give you a license number, or whose number does not check out, is a hard stop. Confirm the license is active and matches the business name on the contract, not just a salesperson's word.
To make this legwork easier, we publish public contractor records: source-labeled profiles of local waterproofing companies showing what is verified in public records, what their own site states, and what still needs confirmation, alongside the basement risk of the communities they serve. Ten verified records are published so far, including Perma Dry Michigan, HomeSpec Waterproofing and Foundation Repair, Michigan Basements, SAS Services, Calculus Foundation Repair & Waterproofing, Swift Dry, Atlantic Coast Waterproofing, The Crack Team, Tom’s Basement Waterproofing, and Dry Basements Plus. The full metro Detroit roster shows who is in verification next.
2. Make them diagnose before they quote
Watch whether they name where the water is coming from before they name a price. Water can enter through a single crack, through hydrostatic pressure across the whole floor, or through a sewer line that backs up in storms, and those have very different fixes at very different costs. A contractor who inspects, explains where the water is coming from, and recommends the least invasive fix that solves it is worth more than one who arrives with a single five-figure "system" for every house. If the diagnosis is vague but the quote is specific, be careful.
3. Read the warranty like a contract, because it is one
"Lifetime warranty" is a common headline and a frequently misunderstood one. Before it means anything, get the specifics in writing:
- What exactly is warranted, a dry basement, or just the one product they installed?
- What voids it? Many warranties exclude the very conditions that cause failures, such as new cracks or seepage at a different wall.
- Is it transferable to the next owner if you sell, and is there a fee or a transfer window?
- Who honors it if the company closes? A warranty is only as durable as the business behind it, which is one more reason to favor an established local contractor.
Michigan does not regulate waterproofing warranties, so the document the contractor hands you is the whole deal. Read it before you sign, not after a failure.
4. Watch for the pressure tactics
The high-pressure sale has tells, and they show up before the quote does:
5. Get three quotes, and compare the same job
On a repair this variable, three written estimates are the single best protection you have. The catch is making sure they are for the same scope: an interior drain, an exterior excavation, and a crack injection can all be called "waterproofing" while differing by tens of thousands of dollars. Ask each contractor to specify the approach, the materials, the warranty, and what is excluded, then compare line by line. Knowing the 2026 cost ranges for metro Detroit ahead of time tells you instantly whether a bid is in the normal zone or an outlier.
6. Match the fix to your actual risk
Know what your house is up against before the sales visit, and the pitch has nowhere to go. A pre-1960 home in a high-risk, combined-sewer part of metro Detroit has genuinely different needs than a newer home on higher ground. Our Basement Risk Index and the 2026 findings show your community's risk profile, from the full 116-community ranking down to high-risk examples like Grosse Pointe, and our guide to what actually keeps a Michigan basement dry walks through which fixes matter most and in what order. Walk into the conversation informed and the pressure tactics stop working.
Sources reviewed
Primary sources checked September 2026:
- Michigan LARA license search, verify a builder's license status, expiration, and disciplinary history by name or number.
- Michigan Occupational Code, MCL 339.2404, the state law requiring a residential builder or maintenance-and-alteration contractor license.
- Michigan Department of Licensing and Regulatory Affairs, the agency that administers and disciplines the license.