Soundproofing Stud Walls with PhoneStar

Soundproofing Stud Walls

There are 2 methods for sound insulating timber or metal stud walls. The system chosen should depend on the level of noise being heard as well as the amount of available room space. The PhoneStar board provides excellent sound insulation due to its high density, high mass and loose, soft silica sand filling. To complement this, the result improves significantly when the PhoneStar board is also decoupled from the wall because this breaks the sound-bridge. These characteristics are the critical parts of soundproofing.

While Option 1 provides the best overall soundproofing solution, it also requires slightly more room space. Option 2 will still provide very good results.

Downloads:

Option 1 - Optimum Solution

Decoupled Stud Wall Solution

Thickness: 44 – 46mm approx.
Expected Improvement: 16 – 18dB approx.

This solution incorporates PhoneStar sound insulation board being installed onto resilient bars which are fitted directly to the studs. We strongly recommend filling the stud cavity with high density mineral wool to absorb more frequencies. The resilient bars are thin, vibration-absorbing, steel channels so these reduce sound transmission through the wall structure. The PhoneStar layer will be almost floating off the stud wall so the sound waves will be dampened due to this decoupled space. This system should easily surpass Building Regulation requirements and offers a very high performance for soundproofing stud walls while still being a very slim system.

Construction

Stud Partition Wall, ideally remove existing plasterboard on one side
Recommended: Fit 45kg/m³ mineral wool to suit stud cavity
16mm Standard Resilient Bars
15mm PhoneStar TRI Acoustic Insulation
12.5 or 15mm Acoustic Plasterboard and skim
(Optional second layer of plasterboard for improved fire and acoustic rating)

Have you also considered Flanking Noise? Flanking Noise is important to consider when installing sound insulation.

Please download the full Installation Instructions for Soundproofing Walls before commencing work.

Materials List

If existing plasterboard has been removed, fill cavity with 45kg/m³ mineral wool
Resilient bars Ref: RB1 (3M x 75mm x 16mm deep)
Drywall screws to secure resilient bars to studs
PhoneStar TRI Acoustic Insulation (1200mm x 800mm x 15mm)
PhoneStar Eco-Tape (50mm x 50M)
Drywall screws (25mm length)
Acoustic plasterboard (2400mm x 1200mm x 12.5 or 15mm)
Drywall screws (38-42mm length)
Acoustic or Intumescent Sealant

Brief Installation Instructions

If existing plasterboard is removed, fill the cavity with 45kg/m³ mineral wool.
Secure the Resilient Bars horizontally to studs at 400mm centres so that the pre-drilled screw holes are at the bottom of the bar. Ensure bar ends do not touch the adjacent walls – leave a 5mm gap. Note: the first and last bars should be approximately 50mm clear of the floor and ceiling.
Hold PhoneStar boards in a landscape formation and screw them into resilient bars only using 25mm drywall screws, being careful to leave screw head just below the board surface. Install the boards in a brickwork formation. Do not leave any gaps between, or around, the PhoneStar layer.
See Cutting and Taping PhoneStar Guide on last page of Installation Instructions.
Screw plasterboard into resilient bars with 38-42mm drywall screws being careful to stagger joints and leave a 5mm perimeter gap around the plasterboard at the floor, walls and ceiling. Optionally add a second layer of plasterboard.
Seal 5mm perimeter gaps with acoustic or intumescent sealant.
Tape and seal all plasterboard joints and fill screw heads.
Fit skirting boards ensuring no contact with the floor – leave a 2mm gap.

Option 2 - Very Good Solution

Direct to Stud Wall Solution

Thickness: 28 – 30mm approx.
Expected Improvement: 10 – 13dB approx.

This Direct to Stud Wall solution offers very good results when soundproofing stud walls and should meet Building Regulations provided that the original wall is well constructed, and that flanking noise is not a major issue. We strongly recommend filling the stud cavity with high density mineral wool to absorb more frequencies. Where space permits, we would highly recommend the Decoupled Stud Wall Soundproofing Solution which will provide even higher noise reduction through timber or metal stud walls.