GSI Foundations: Waterproofing service in Germantown, WI

The service provider, as administrator of the site, does not verify whether the opinions published on the site come from consumers who have purchased or used the product or service in question. The rating in stars (up to 5) is the arithmetic average of all ratings given within the reviews published below.

• Craig Konkle

  • 5,0
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  “I’ve been working with GSI for over ten years now, and I’m incredibly happy with the team – Dave, Jodi, Matt, Toni, and May – they’re a fantastic group, and I plan on continuing to work with them for the foreseeable future. We use GSI for around six to eight basement renovations each year as part of our home rehabbing business, and we’ve been consistently pleased with their service.” report abuse

• blake retzer

  • 5,0
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  “I’ve been working with GSI for years now and I’ve always been incredibly pleased with their service. My clients have consistently thanked me for recommending them for foundation work – they’re reliable, honest, and offer competitive pricing. I wholeheartedly recommend them to anyone needing this kind of work.” report abuse

• Monika Chudzik

  • 5,0
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  “We had some persistent flooding issues in our basement over the years, and we couldn’t figure out the cause. It wasn’t until we contacted a foundation specialist that we learned GSI Solutions had actually installed a drain tile in our basement back in 2016. They explained that this was likely the source of the problem.” report abuse

• michael williams

  • 5,0
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  “I was really impressed with GSI. Not only did they offer the best price I found, but the team was absolutely fantastic – truly the most professional and hardworking crew I’ve ever encountered. They completely renovated my basement over two days, even during a crazy snowstorm, and I don’t think they took a single break. I wholeheartedly recommend them.” report abuse

• Jodi WB

  • 5,0
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  “I’ve been incredibly impressed with the team at GSI. They’ve been a huge help on multiple rental properties, tackling everything from bracing and excavation to interior drain tile work. And it’s not just been with the rentals – they’ve also done some work on my own home over the years. Because of their reliability and honest approach, I genuinely trust them completely.” report abuse

• Bryan Thiermann

  • 5,0
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  “We contacted GSI Foundations before starting our basement remodel because we had some cracking issues and wanted to make sure the foundation, particularly the sections repaired back in the 80s with the undersized bracing, was still sound and structurally intact.” report abuse

• Jon Eastman

  • 5,0
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  “GSI Foundations consistently delivers excellent work and keeps projects on schedule – we’ve used them on multiple occasions and would definitely engage them again for future needs.” report abuse

• Karen Dupont

  • 5,0
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  Overall, I had a really positive experience with GSI. They were incredibly responsive to my call and arrived exactly when they said they would. The team was very thorough in their inspection, checking both the inside and outside of my property, and they gave me a clear and fair estimate. I was really impressed with their professionalism and how attentive they were to detail – I’d definitely recommend them. report abuse

• E A

  • 5,0
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  “GSI Foundation did a fantastic job with our foundation work and pump installation back in June 2025. They were incredibly responsive and communicative throughout the whole process – really went above and beyond. We’d absolutely recommend them!” report abuse

• Regina Lester

  • 5,0
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  “As a realtor with two decades of experience, I’ve consistently found GSI to be a truly reliable and supportive partner. I’ve worked with them on several projects for my sellers, and every interaction has been professional, comfortable, and refreshingly honest. You can definitely trust them to give you an open and truthful assessment.” report abuse