Acoustic Soundproofing Renovation in Ajax

Reference points: STC 25 (normal speech clearly understood — typical bare-wall partition), STC 35 (normal speech audible — typical batt-insulated 2x4), STC 45 (loud speech faintly heard — better interior wall), STC 50 (loud speech faintly heard, normal speech inaudible — OBC 9.11 mandate between dwelling units), STC 55 (only very loud sounds carry — premium townhouse), STC 60+ (recording-studio level). For multiplex unit-to-unit walls and floors: minimum STC 50 / IIC 50 by OBC. For condo neighbour problems: typically Tier 2 (STC 53–58) solves most issues. For home recording: Tier 3 (STC 65+).

Single shared wall Tier 1 basic ($3–5/sqft, 80 sqft wall): $400–$800. Single shared wall Tier 2 OBC compliant (100 sqft, $8–12/sqft): $1,000–$1,500. Whole condo unit shared walls and ceiling (Tier 2, ~400 sqft surface): $5,000–$8,000. Multiplex unit-to-unit OBC compliance (whole semi-to-duplex conversion, ~1,000 sqft assembly): $10,000–$18,000. Premium recording-studio room-within-room (Tier 3, ~150 sqft): $12,000–$20,000. Whole-home premium quiet renovation: $15,000–$25,000+.

Tier 1 ($3–5/sqft): mineral wool + resilient channel + single 5/8" drywall. Improves STC ~35 to ~45–48. Best for in-suite quiet rooms, home offices, and budget condo work. Tier 2 ($8–12/sqft): mineral wool + RC + double 5/8" Type X drywall with Green Glue between layers + acoustic sealant detailing. Achieves STC 53–58, exceeds OBC 9.11. Best for multiplex/condo and serious neighbour-noise problems. Tier 3 ($50–80/sqft): room-within-room with AcoustiClips/Resilmount, double QuietRock 530 each side, floating floor, sealed acoustic doors, acoustic ventilation. Achieves STC 65+ / IIC 65+. For studios and premium.

Standalone in-suite soundproofing typically does not require a building permit — no structural changes, no electrical or plumbing modifications, no fire-separation alterations. Combined with multiplex conversion, the whole project is under the building permit (which includes the soundproofing scope per OBC 9.11). Combined with renovation that affects load-bearing walls, electrical, or plumbing — those triggers require a permit, and the soundproofing is part of the permitted scope. Condo work also requires condo board approval; we handle the noise-bylaw timeline and freight-elevator booking.

Insulation: Roxul Safe'n'Sound mineral wool (industry-standard, NRC 1.05 absorption, fire-rated). Damping compound: Green Glue Compound (between double drywall, 9–12 STC point improvement). Resilient channel: RC-1 (standard) or RSIC AcoustiClips (premium). Drywall: 5/8" Type X (fire-rated standard) or QuietRock 530 (premium acoustic-laminated). Sealant: Tremco Acoustical Sealant. Mass-loaded membrane (premium): Tecsound 70 (1.5 lb/ft² from Soprema). Floor isolation: Maxxon Acousti-Mat under engineered-wood or LVT, QT Floor under laminate. Resilmount mounts for premium wall decoupling.

Limited improvement only. Adding a layer of 5/8" drywall to one face with Green Glue between (single-side overlay): improves STC by 6–9 points (e.g., 35 → 41–44) — meaningful but not OBC compliant for multiplex use. For OBC STC 50 compliance, the wall must be opened: existing drywall removed, mineral wool added (or upgraded), resilient channel installed, double drywall with Green Glue applied. Realistic budget for retrofit: 1.4x to 1.8x the cost of soundproofing during new construction or open-frame renovation.

Impact noise is rated by IIC (Impact Insulation Class), the floor analog of STC. OBC requires IIC ≥ 50 between dwelling units. Solutions: (1) Floor side — add Maxxon Acousti-Mat or QT Floor underlay under flooring (IIC improvement 8–15 points), or floating concrete topping for premium IIC 60+. (2) Ceiling side (work from below) — RC + double drywall with Green Glue + mineral wool (IIC improvement 8–12 points combined with STC). Most condo-noise problems require treating BOTH sides — neighbour upgrades floor underlay, you upgrade ceiling assembly — for adequate impact mitigation.

No. Acoustic and soundproofing work is standard renovation construction — framing, insulation, drywall, sealant — performed by general carpentry and drywall trades. No special licensing is required. RenoHouse self-performs all soundproofing work with our own crews. The materials are specialty (Green Glue, Tecsound, QuietRock, AcoustiClips) but the installation methods are standard. We've delivered Tier 1 through Tier 3 projects across Ajax since 2013.

Single wall Tier 1: 1–2 days. Single wall Tier 2 (with Green Glue cure time): 3–4 days. Whole condo unit Tier 2 (walls + ceiling): 1–2 weeks. Multiplex full unit-to-unit OBC compliance (semi-to-duplex): 2–4 weeks (combined with the rest of the conversion). Tier 3 room-within-room recording studio: 3–6 weeks (specialty doors and ventilation add lead time). Permit and condo-board approval (when applicable) adds 2–4 weeks before construction.

Most Ajax condo boards have noise bylaws restricting renovation hours (typically Mon–Fri 9am–5pm or 10am–4pm, no weekends), require freight-elevator booking, and require renovation insurance and approval of plans. Soundproofing renovations are usually straightforward to approve because they REDUCE noise transmission to neighbours — many boards welcome them. We handle the renovation form submission, schedule freight-elevator bookings, and follow the approved hours. Our condo-renovation experience covers all major Ajax buildings.