Word pyrite makes many owners of single-family homes in Montreal and Longueuil shudder. Indeed, this scourge which caused so much talk during the 1990s and 2000s seems to have faded a little, but is still present. Pyrite can cause serious foundation problems and, thereby, reduce the value of your home. Therefore, when selling or buying a property, it is important to know the pyrite index that is under the foundation of your house to avoid unpleasant surprises. If you need to undertake work, rent a container Recybac!
What is pyrite?
There pyrite is a mineral that is found under the concrete slab of many houses. Subjected to humidity and oxygen, it oxidizes, creating a gas which puts pressure on the concrete slab and which can crack it, causing considerable damage to the foundation. When you visit a basement or garage that displays cracks in the floor, there is a good chance that it is because of pyrite. It should be noted that pyrite is not harmful to health.
The pyrite detection test
Several companies offer pyrite detection tests. By creating a small hole in the foundation, they can take a sample of the backfill and determine the presence of pyrite under the house. The test result is then given as a Petrographic Swelling Potential Index (IPPG) from 0 to 100. From 0 to 10, the risk of cracks is extremely low, or even zero. However, the higher the value, the greater the chances of contracting a foundation problem. However, you shouldn't be stressed about a high value: a home built in the 1960s that has yet to experience any apparent pyrite problems has a very low risk of becoming problematic in the next few years.
Removing pyrite
Removing pyrite is a complex and expensive operation, because the concrete slab of the basement must be demolished in order to extract the backfill contaminated by pyrite. It is therefore necessary to remove all objects found in the basement, remove the floor and demolish the partitions in order to remove the concrete slab. It goes without saying that such an operation generates a lot of construction waste and it is necessary to rent a container to avoid the accumulation of debris.
Once the contaminated backfill has been replaced, the floor and partitions must be replaced, an operation which is also as costly as having to redo your basement full.
In the end, before buying a property, it is very important to obtain the pyrite test report. If it is positive, make sure to negotiate the price of the house accordingly and deal with professionals to prevent the situation from getting worse. To manage construction site waste, don't forget to rent a Recybac container!
