What is the cost to add soundproofing between the main floor and basement in a GTA home?

Soundproofing between the main floor and basement in a GTA home costs between $3,000 and $12,000, depending on the area being treated, the level of sound reduction required, and the methods used. For a typical 800 to 1,000 square foot basement ceiling, a solid soundproofing assembly costs $4 to $10 per square foot, achieving a significant reduction in both airborne noise (voices, music, television) and impact noise (footsteps, dropped objects).

The most effective and cost-efficient basement ceiling soundproofing assembly uses three key components working together. First, mineral wool sound batts (Roxul Safe'n'Sound or Rockwool) are installed between the floor joists — these dense batts absorb sound energy as it passes through the cavity. The batts cost $1.50 to $2.50 per square foot and provide significant improvement on their own, but they work best as part of a complete assembly. Second, resilient channel (hat channel) is screwed horizontally across the underside of the joists, and the drywall is then screwed to the resilient channel rather than directly to the joists. This creates a decoupled connection — the drywall is physically separated from the structure by the springy resilient channel, which dramatically reduces the transmission of vibration and impact noise. Resilient channel costs $1 to $2 per square foot installed. Third, one or two layers of 5/8-inch drywall (standard or Type X) are screwed to the resilient channel. Using two layers with Green Glue compound ($15 to $20 per tube, approximately one tube per 16 square feet) sandwiched between them provides the highest performance — the Green Glue converts sound energy to heat as it passes between the drywall layers.

This complete assembly — mineral wool batts, resilient channel, double drywall with Green Glue — achieves an STC (Sound Transmission Class) rating of 55 to 60, which is considered excellent for residential construction and makes normal conversation and television in one unit essentially inaudible in the other. By comparison, a standard basement ceiling with single drywall screwed directly to joists achieves an STC of approximately 35 to 40, meaning voices and music are clearly audible.

For secondary suites, soundproofing takes on additional importance beyond comfort. While the Ontario Building Code's fire separation requirement (1-hour rated assembly with two layers of 5/8-inch Type X drywall) provides some sound reduction as a byproduct, it does not achieve the level of acoustic privacy that tenants expect. Adding resilient channel and mineral wool batts to the fire-rated assembly costs only $2 to $4 per square foot additional and makes a transformational difference in livability — this is one of the highest-value upgrades in a secondary suite build.

Impact noise (footsteps, children running, dropped objects) is the most difficult to control and the most common complaint in homes with finished basements. Resilient channel is effective against impact noise, but for maximum impact noise reduction, consider adding acoustic floor underlayment on the main floor above — a dense rubber or cork mat installed under the main floor's finished flooring. This costs $1 to $3 per square foot and addresses impact noise at the source rather than at the ceiling below.

One critical installation detail: resilient channel only works if it is the sole connection between the drywall and the structure. If even a single screw penetrates through the resilient channel and into the joist (called a short circuit), it creates a rigid connection that bypasses the channel and dramatically reduces its effectiveness. This is one of the most common installation errors, and it is why professional installation by a crew experienced in soundproofing is strongly recommended over DIY attempts. An improperly installed resilient channel ceiling can actually perform worse than drywall screwed directly to the joists.