Floor Joist Isolators (Case of 100)

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    Made in USA

Floor Joist Isolators (Case of 100)

Floor Joist Isolators are a U-shaped isolation product constructed from a medium density thermoplastic which is designed to isolate vibration and structural noise transmission. Floor Joist Isolators improve a flooring assembly’s Sound Transmission Class (STC) and Impact Insulation Class (IIC) by decoupling the flooring from the structural supports which provides a reduction of sound transmission, especially the hard to control low frequency sounds. The Stud Beam Isolators are sized to fit any 2X lumber product, are very easy to install and are best used for new construction when floor joists are exposed.

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Weight 40 lbs
Thickness 1 1/4 in.
Weight 40 lbs./case
Coverage 128 sqft. when placed on 16 in. centers
Quantity Case of 100
Availability Usually ships in 1-3 business days

Floor Joist Isolators for Vibration Noise

Airborne noise isn’t the only sound you need to block if you are trying to create a quiet, soundproof environment. You also have impact noise to contend with, and some of the greatest impact noise can come from your floor. For improved soundproofing of a floor, order Floor Joist Isolators from Soundproof Cow.

What Is a Floor Joist?

A floor joist is a horizontal beam above the foundation that transfers weight to the vertical beams. Most floor joists are single or double and are common in houses built on top of basements or wooden foundations. Joists help enclose the foundation and improve the structural integrity of the entire home. The rest of a flooring system is then built on top, like the subfloor and underlayment.

What Are Flooring Joist Isolators?

If you’re not familiar with Floor Joist Isolators, these U-shaped thermoplastic pieces fit easily over floor joists to improve both the Sound Transmission Class (STC) and Impact Insulation Class (IIC) of your flooring assembly. They do this by isolating the flooring from the structural supports. This prevents vibrations and vibrational noise from traveling through the structural supports and transmitting sound into the room through the floor.

We make our floor joist isolators with a medium-density thermoplastic that is common as a vibration-dampening solution in industrial machinery. The result is a product that improves your floor’s Impact Insulation Class (IIC) and Sound Transmission Class (STC). These isolators reduce sound transmission, specifically low-frequency sounds.

In addition to their enhanced effectiveness, our flooring joist isolators are easy to install. Each isolator fits over any wooden floor joist with a width of two inches, and you do not need glue, adhesives or tools to install them, so you can easily soundproof your professional and home movie theater, recording studio or band practice room. They’re best installed in new construction projects, where the joists are currently exposed and easy to access.

A Great Go-To for DIY Projects

These Floor Joist Isolators can be useful in a wide variety of situations but are especially helpful in a do-it-yourself soundproofing project. These joist isolators fit right in place with no tools required, so anybody can make use of them.

Floor soundproofing is often neglected when building soundproof environments. It is tempting to think all sound can be controlled through the walls. But if you want a complete soundproofing solution with dramatically reduced impact noise, Floor Joist Isolators are an important part of your overall soundproofing design. Floor Joist Isolators from Soundproof Cow are quite affordable, especially when you buy them in larger quantities, so order yours today.

Product Availability

Case of 50 (64 sqft when place on 16 in. centers)

Case of 100 (128 sqft when place on 16 in. centers)

Features / Benefits

Good Soundproofing Performance — Floor Joist Isolators are attached to floor joists in order to structurally isolate floor surfaces, including substrates, from the structural support elements. They are a cost effective product that reduces sound transmission through floor or ceiling assemblies. Floor Joist Isolators are perfect for applications that use the “Box in a Box” or “Room in a Room” construction methods commonly used when building a professional home theater or recording studio environment.

Quality — Floor Joist Isolators are made from a medium density thermoplastic that is commonly used to make vibration isolation feet or vibration damping pads for large industrial machinery. The raw material is a time tested vibration isolating material.

Ease of Installation — Floor Joist Isolators are friction fit over any wood with a 2 inch width (actual width equals 1.5”). No messy glues or adhesives are needed to install is product. No tools required!

Cost Effective Soundproofing — Floor Joist Isolators are our most cost effective sound isolation product due to the ease of installation. Labor costs are minimal to install this product.

Light Weight and Low Profile — Floor Joist Isolators are designed to provide effective soundproofing performance with minimum added weight and thickness. The low profile maximizes valuable square footage.

In-stock — We stock Floor Joist Isolators in large quantities. Most orders are filled and shipped the same day the product is ordered.

Made in the USA


Great for:

  • Professional and Home Theaters
  • Professional and Home Recording Studios
  • Band practice rooms
  • Broadcast Studios
  • Any environment that uses “Room in a Room” or “Box in a Box” construction method

Product Dimensions

Floor Joist Isolator Diagram

Installation Details

Tools Needed: None

Materials Needed: None

Customer Reviews

Average Customer Ratings: 4.8 (34 reviews)

The times I talked with you on the telephone and corresponded through email you have been very helpful and efficient. I would highly recommend Soundproofcow.com to anyone!

– S. Cimino, PA

I have emailed a lot of different manufactures and I have to say your customer service is head and shoulders above all of them. I emailed your company at about 9pm my time and when I woke up the next morning you had already answered my question and then the follow up was a few hours later. I am impressed. Thanks a lot for the quick turn around!

– E. Gustafson, NV

I just wanted to send a quick thank you for your rapid response and helpfulness. I very much appreciated it. You have been responsive in every way all through the process. It has been a pleasure doing business with you and your company.

– T. Alexander, CA

I just wanted to let you know that in the end, sealing the air spaces on this door worked just fine and took care of the problem.

I really appreciate you taking so much time to share your expertise with me, and in particular recommending I try the simpler solution before investing in more expensive noise barriers. That is a big credit to you and your business.

– Mike

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