Airborne Noise From Below

Primary Suggestion: Green Glue Compound Damping System

Here's what you will need:

• Green Glue Compound (1 tube per 16 square feet of ceiling)
• Another layer of sub-floor material (1/4" Hardiboard or standard plywood sub-floor is recommended)
• Insulation for joist cavity if it is not already insulated (blown in before second layer of sub-floor is attached)
• Acoustical sealant for floor perimeter

Rating: Estimated at 46 STC. Adding a third layer of sub-floor and second layer of Green Glue Compound increases rating to an estimated 49 STC.

Cost: Estimated at about $.95 per square foot per Green Glue Compound layer plus the cost of sub-floor material (typically .75 cents per square foot) and plus the cost of labor.

Secondary Suggestion: QuietGround Rubber Underlayment

Here's what you will need:

• QuietGround Rubber Underlayment (QG 250 or QG 375)
• Insulation for joist cavity if it is not already insulated (blown in before second layer of sub-floor is attached)
• Acoustical sealant for floor perimeter

Rating: Estimated at 49 STC with QG 250 and 52 STC with QG 375. Estimates based on hard surface finish floor over wood sub-floor.

Cost: Estimated at about $1.75 per square foot for QG 250 and $3.25 per square foot for QG 375 plus the cost of labor.

DO NOT USE mass loaded vinyl, sound board, acoustic foam, specialty insulation, or any other similar product to isolate airborne noise from passing through your floor from the room below. These products are not effective enough to significantly improve isolation in your floor.