Pyrite in Basement Appartment

Question Icon
Posted by: from Saint Leonard
4/17/2008 at 2:25:18 AM

Because of severe heaving and cracking of basement foundation, I tested for pyrite which results were positive. Wondering if anyone has advice on the best way to find a contractor or if anyone can recommend one. Also if anyone has advice on how much i'm looking at in terms of cost for about 1100sq ft.


User Icon
Date/Time4/18/2008 at 10:24:01 PM

Hi Vince, We have extensive basement experience, both new and old, but I've never heard of the world Pyrite? Can you explain further. Thanks


User Icon
Jesse in Saint Leonard
Date/Time4/19/2008 at 12:20:59 PM

hi Joe, I'll just give you a quick history about it first. Pyrite is a mineral commonly known as "fools gold." Back in the mid 60's montreal was digging its subway network and the rocks and stones were then used as backfill for construction of new homes and buildings. Now what happens over time is that pyrite oxidises and procduces sulfuric acid. The acid then reacts with calcium carbonates and forms gypsum whose crystallization will cause stone to burst and backfill to swell and concrete to crumble. It actually is a very slow process and takes years for damage to appear. Its why it took until mid 90's for the city of montreal to notice that it wasn't isolated incidents. So levels of severity varies, but in my case the swelling has caused a 3ft round speed bump in my basement wooden floor. So basically the concrete slap has to be broken and the backfill has to be excavated and refilled with non pyrite backfill. So we are looking at extensive work and repair. Hope this helps

User Icon
Abba's Service in Huntsville
Date/Time6/11/2008 at 7:52:51 PM

I am sorry but I get a chuckle when a contractor with a logo say's construction on it doesn't know what pyrite is. Not to say bad things but Are you trying to hurt your business or what! If anybody should know what this stuff is it should be a construction guy! I am a renovation's guy and we do do Quality work but I am sorry we don't do that type of work I just wanted to laugh.

Search the TrustedPros directory and discover the best contractors in your area.

Find your home service pro
Great renovations start with a great contractor.

Since 2004, TrustedPros has been helping homeowners find the right contractor for their home improvements and repairs.

Post Your Project

Within hours you'll be comparing offers from top-rated professionals. It's free to post and you're under no obligation to hire.

Trustedpros Inc. does not warrant the accuracy, completeness, safety, legality or usefulness of any Content, or Whether Content is Current and up-to-date, and TrustedPros Inc. Shall have no liability whatsoever with respect to your use or reliance upon any content or for content being removed or otherwise ceasing to be available. Please refer to the terms and conditions of use of this websites for more details.

Get Free Estimates

Post your project and compare offers from top-rated pros.