Reference installation
Condominium over concrete slab
What does a correct hardwood installation over a Toronto condo slab look like, end to end?
The most common non-trivial scenario in the GTA: an engineered floor glued to a concrete slab, in a building with acoustic requirements and no forgiving substrate.
Specification
The assembled specification
- Substrate
- Concrete slab
- Product construction
- Engineered — hardwood wear layer over 90° cross-ply core
- Method
- Glue-down
- Acclimation
- Minimum 72 hours in the actual conditioned space
- Moisture testing
- Slab and material, documented, at estimate and again before installation
- Operating band
- 35–55% RH
- Dust containment
- HEPA throughout the process
Sequence
The sequence, start to finish
- Moisture-test the slab and the material; document both readings.
- Confirm both readings sit inside the acceptable delta before ordering.
- Acclimate a minimum of 72 hours in the actual conditioned space.
- Assess and correct slab flatness before the price is fixed.
- Confirm the building's acoustic requirement and how the assembly satisfies it.
- Glue-down installation, with expansion gaps at every wall and fixed object.
- HEPA containment maintained throughout.
Failure modes
Where this goes wrong
- Solid hardwood over a slab has no cross-ply core to resist seasonal movement. This is the substitution that fails most often.
- Slab flatness discovered after the deposit is the single most common source of change orders.
- Expansion gaps are missed at fixed objects mid-field far more often than at the perimeter.
Answer
What we recommend
Engineered, glued down, over a slab that has been tested and flattened before the price was fixed. Nothing in this scenario is negotiable on budget grounds.
Provenance
Where every claim on this page comes from
- Climate Mastery — method and substrate
- Climate Mastery — protocol
- The Intelligent Homeowner's Decision Framework — decision tree
- The Intelligent Homeowner's Decision Framework — fixed price