Overview
Sub-slab depressurization systems (SSDS) are a risk management measure to vent harmful vapours that accumulate below a building concrete floor to treatment systems or directly to atmosphere. These systems are primarily instituted on pre-existing building structures that experience vapour accumulation below the concrete slab or basements from a pre-existing contamination source located below the building footprint. SSDS’s are a cost effective way to mitigate vapour intrusion into building spaces without major excavation.
There are several points of vapour intrusion that can be found in all buildings:
- Slab cracks
- Sump pit penetrations
- Footing joints
- Slab extensions
- Utility penetrations
Vapour migration from below the building slab into the slab can happen naturally over the life of the building, depending on the contaminant of concern. Harmful compounds, such as perchloroethylene (PCE) have a size of approx. 1um while natural pore spaces in cured concrete can be as large as 10um in diameter. The frequency of these void spaces make concrete a passive barrier to these vapours to a small degree, however the accumulation of vapours below the slab increase the risk for natural migration of these contaminants into occupied spaces.
Experience
Having an experienced sub-slab depressurization contractor for your next project is critical to ensuring that vapours are vented and treated properly. Vertex has experience across Ontario in permitting, installing and maintaining of sub-slab depressurization vapour mitigation systems. On your next vapour intrusion related project, Vertex can provide support in all aspects of the system install, from piping layout to long term servicing.
Contact Vertex to see if a sub-slab depressurization mitigation system is right for your next project at info@vertexenvironmental.ca.
