WindowPlug: Studio-Grade Soundproofing for Windows

The ASC WindowPlug is perfect for reducing sound transmission through windows without permanently sealing the window. Like all ASC soundproofing products, WindowPlug uses our exclusive WallDamp visco-elastic material to eliminate vibration. The unique assembly provides improved sound quality within the room, while reducing noise levels inside and outside.

Each WindowPlug is custom sized to fit your window opening. You provide a series of very accurate measurements for our shop to replicate the exact shape of your window frame. Pricing is determined by the square footage of the WindowPlug.

The unit is friction fitted into place using the perimeter felt gasket to hold it firmly. These units use mass and vibrational damping to stop sound. The density is quite high such that many window openings require the use of two separate sections. For example, a 4'x4' window would use (2) sections that are each 2' wide and 4' tall, at a total cost of about $1500 plus shipping.

The deluxe version includes a beautiful oak frame and your choice of fabric from Guilford of Maine, priced at $780 each for sections approximately 2'x4'. The economy version includes a frame made from black lacquered MDF with black felt on the front and back of the unit, priced at $650 each for sections approximately 2'x4'. (see pricing tab for details)


  • High End Audio Listening Rooms
  • Professional Recording Studios
  • Home Recording Studios
  • Home Theaters
  • High-End Residential Soundproofing
  • Commercial Soundproofing

How It Works

The biggest single soundproofing problem in homes is the window. It is the weakest link when it comes to sound containment. You could buy expensive retrofit “soundproof windows” and still only achieve STC 34, which still allows a lot of sound penetration. Or you can save the remodel expense and hassle and just get a custom sized ASC WindowPlug. Keep your existing window, and get excellent soundproofing results instantly.

The WindowPlug excels at reducing road and traffic noise intrusion into your bedroom or workspace.  Landscaping equipment, utility trucks, neighboring dogs, heat pumps, backup generators...the list goes on of the nuisances you will be able to block from interrupting your peace and quiet.  

If you are the one making noise (mixing down your latest recording, wailing out an electric guitar solo, watching 2001: A Space Odyssey, or performing home dentistry), the Window Plug can be installed and removed as needed to maintain the peace in your neighborhood.

HiFi enthusiasts may be amazed to learn of the benefits a WindowPlug can bring to the sonic performance of their rooms.  The rumble/twang of a 

glass window can wreak havoc on a finely sculpted stereo image and smooth frequency response.  Cupboards and cubbies can introduce honking and tonally colored reflections to smear the lovely soundscape you have worked so hard to achieve.  When it comes down to it, almost any opening in your wall can unsettle the balance and symmetry of your system.  The WindowPlug can fit into almost any opening in your wall, so it could be the secret solution that you never even thought of.



We will do everything possible to ensure that your WindowPlug fits perfectly into your opening of choice.  The final goal is for the wooden-frame portion of the WindowPlug to rest approximately 1/8" inside of your opening around the entire perimeter, with the green technical felt supplying adequate friction to keep the unit in place.  This means that the unit you receive should be slightly larger than the opening, when measured by the size of the felt.

The way we accomplish this is only through precise measurements provided by YOU, the customer.  We typically require six measurements to be provided with each WindowPlug order.  By analyzing these measurements performed at various locations, we are able to determine how far out of square your opening actually is (hint: every window we have ever  worked with was slightly out of square!). Depending on several factors, price or design revisions may be made at this point in the process.

For the accuracy of these measurements, measure the INSIDE of the window frame. We need measurement of the width of the top and bottom (C and D), the height of both sides (A and B) and the diagonal measurements from each opposite corner (E and F).

After everyone agrees upon the final size and shape of your WindowPlug, the unit is handcrafted and left to cure for a minimum of 10 days prior to shipment, to minimize warping during shipment or installation.  The size of most WindowPlug units requires motor freight shipment using a pallet, so order consolidation is important in keeping costs low.



Deluxe WindowPlug (includes hardwood frame and finish with Guilford of Maine fabric): $499+$35/square foot (+ design fees if applicable)

EXAMPLE: a Deluxe WindowPlug for a 2'x3' window would cost $709.00 before shipping.

Utility WindowPlug (includes black lacquer MDF frame finish with black felt): $449+$25/square foot (+ design fees if applicable)

EXAMPLE: a Utility WindowPlug for a 2'x3' window would cost $599.00 before shipping. 

Shipment is typically via motor freight, with larger orders receiving better rates per unit.  Remember to request a liftgate for residential pallet deliveries.