Learning center / STC ratings and soundproofing
STC ratings and soundproofing
What STC, OITC and IIC mean, the techniques that block sound, and typical ratings for common wall assemblies. 36 guides.
What the ratings mean
What is an STC rating?Sound Transmission Class explained in plain language, with a chart of what each rating sounds like. · 2 minSTC vs NRC: blocking sound vs absorbing itThe difference between the two ratings and which one your problem needs. · 2 minOITC: the rating for traffic, trains and aircraftOutdoor-Indoor Transmission Class and why it matters for windows and exterior walls. · 2 minIIC: impact noise through floorsImpact Insulation Class explained, with targets and the best upgrades. · 2 minSTC ratings chart: what each number sounds likeA quick reference for choosing a target STC. · 2 minLab STC vs field ratings (FSTC, ASTC, NIC)Why a wall rarely performs as well in a building as it did in the lab. · 2 min
Soundproofing techniques
Soundproofing technique: add massHow mass blocks sound, the mass law, and practical ways to add it. · 2 minSoundproofing technique: decouplingResilient channel, isolation clips, staggered studs and double walls. · 2 minSoundproofing technique: damping compoundConstrained-layer damping between drywall layers. · 2 minSoundproofing technique: seal gaps and stop flankingWhy small gaps and indirect paths ruin good walls, and how to close them. · 2 minSoundproofing technique: cavity insulationWhat filling the wall cavity does for STC, and which insulation to use. · 2 minDoors and STC: the weakest linkDoor STC ratings and how to upgrade a door for privacy. · 2 minWindows and STCGlass types, air gaps and secondary glazing for quieter rooms. · 2 minOutlets, pipes and other penetrationsKeeping small holes from undoing a soundproof wall. · 2 min
Wall and floor assemblies
Single wood stud wall, no insulation: STC 33Layers, typical STC, cost level and upgrade options for a Single wood stud wall, no insulation. · 2 minSingle wood stud wall, insulated: STC 36Layers, typical STC, cost level and upgrade options for a Single wood stud wall, insulated. · 2 minSingle stud wall, two layers of 5/8 in drywall each side: STC 45Layers, typical STC, cost level and upgrade options for a Single stud wall, two layers of 5/8 in drywall each side. · 2 minWood stud wall with resilient channel: STC 50Layers, typical STC, cost level and upgrade options for a Wood stud wall with resilient channel. · 2 minResilient channel with double drywall: STC 55Layers, typical STC, cost level and upgrade options for a Resilient channel with double drywall. · 2 minStaggered stud wall: STC 48Layers, typical STC, cost level and upgrade options for a Staggered stud wall. · 2 minStaggered stud wall, double layer one side: STC 52Layers, typical STC, cost level and upgrade options for a Staggered stud wall, double layer one side. · 2 minDouble stud wall: STC 56Layers, typical STC, cost level and upgrade options for a Double stud wall. · 2 minDouble stud wall, double drywall: STC 63Layers, typical STC, cost level and upgrade options for a Double stud wall, double drywall. · 2 minSteel stud partition, 25 gauge: STC 45Layers, typical STC, cost level and upgrade options for a Steel stud partition, 25 gauge. · 2 minSteel stud partition, double layer: STC 51Layers, typical STC, cost level and upgrade options for a Steel stud partition, double layer. · 2 minIsolation clips and hat channel: STC 58Layers, typical STC, cost level and upgrade options for a Isolation clips and hat channel. · 2 minDouble drywall with damping compound: STC 52Layers, typical STC, cost level and upgrade options for a Double drywall with damping compound. · 2 min8 in hollow concrete block, painted: STC 45Layers, typical STC, cost level and upgrade options for a 8 in hollow concrete block, painted. · 2 min8 in concrete block, grout filled: STC 51Layers, typical STC, cost level and upgrade options for a 8 in concrete block, grout filled. · 2 minConcrete block with furred drywall: STC 58Layers, typical STC, cost level and upgrade options for a Concrete block with furred drywall. · 2 min6 in concrete wall: STC 55Layers, typical STC, cost level and upgrade options for a 6 in concrete wall. · 2 min8 in concrete wall: STC 58Layers, typical STC, cost level and upgrade options for a 8 in concrete wall. · 2 minSingle-wythe brick wall: STC 45Layers, typical STC, cost level and upgrade options for a Single-wythe brick wall. · 2 minDouble-wythe brick wall: STC 52Layers, typical STC, cost level and upgrade options for a Double-wythe brick wall. · 2 minSingle-glazed office front: STC 33Layers, typical STC, cost level and upgrade options for a Single-glazed office front. · 2 minDouble-glazed acoustic office front: STC 48Layers, typical STC, cost level and upgrade options for a Double-glazed acoustic office front. · 2 min