For retrofit, consider two layers of drywall with damping compound over existing studs, or add resilient channels to decouple the new surface. New construction can use double studs or staggered studs for deeper separation. Combine with dense insulation to tame cavity resonance. Match ambition to budget, and target rooms where peace brings the greatest daily benefit.
A wall’s weakest link is often a pencil-wide crack near trim, outlets, or baseboards. Use acoustic sealant at perimeters, caulk around boxes, and install putty pads behind outlets. Top and bottom plates deserve special attention. Even a modest assembly can outperform expectations when airflow is controlled, because sound rides the same sneaky paths that drafts love to follow.
If boutique materials seem pricey, start with strategic mass where it matters most, and focus on airtightness. Use common gypsum board in double layers with damping compound, choose mineral wool over foam for sound absorption, and repurpose bookshelves on shared walls. Small, well-placed measures build upon one another, creating meaningful day-to-day quiet without major demolition or designer price tags.