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Wall Insulation - Interior

An interior wall is any wall that does not face outside. You may think that such walls do not require insulation. However, interior wall insulation adds significantly to the enjoyment of peace, privacy and comfort in your home by keeping sound from migrating from one room to another. Interior wall insulation also contributes to your home's overall energy efficiency.

Home construction is fairly standardized, so insulating an interior wall in one room will be the same as insulating an interior wall in any other room. JM insulation is manufactured in standard widths designed to fit the most common wall cavities. However, occasionally you may encounter nonstandard-width wall cavities. In fact, up to 35% of cavities in newer homes are non-standard widths. In these situations, you will probably find our EasyFit® Batts to be the best solution.

EasyFit® insulation features vertical perforations that allow you to easily tear the insulation by hand. The perforation pattern accommodates most non-standard-width cavities. Or if you use JM ComfortTherm®, Kraft-faced or Unfaced batts, you can cut them by hand with a utility knife using a 2x4 as a straight edge.


How to Install Insulation in Interior Walls

  1. To install in interior walls for good sound control, apply caulk between the top plates and at the bottom plate and floor. You should apply sealants or caulks only to clean, dry, oil-free surfaces. Smooth caulking with your fingertip or a putty knife.
  2. If you are using faced batts, place the batts into the wall cavity and staple the flanges of the batts to the inside or the face of the studs about every 12". If you are using unfaced batts, place the insulation into the cavity, making sure that it is the correct size and fits snugly at the sides and ends and does not protrude in the back.
  3. If the insulation is too long, cut it to fit properly. Don't double it over or compress it. Use a sharp utility knife and straightedge. Cut batts on a smooth, flat surface, and cut them about 1" larger than the framing cavity. If the material is too short, cut a piece to size to fill the gap.
  4. Fill in any narrow gaps between joists by forcing pieces of unfaced insulation into the gaps with a screwdriver or putty knife.

Related Products

ComfortTherm® Batts and Rolls


ComfortTherm® insulation is a lightweight, thermal and acoustical insulation made of long, resilient glass fibers bonded with an acrylic thermosetting Formaldehyde-free™ binder.

EasyFit® Batt Insulation


JM's EasyFit® Formaldehyde-free™ insulation is available unfaced or with kraft facing, and has vertical perforations for fitting non-standard wall cavities.

Kraft-Faced Batts and Rolls


JM's Kraft-Faced Batts & Rolls are made of naturally white, Formaldehyde-free™ fiber glass, reducing environmental concerns including the risks of poor indoor air quality and the effects of manufacturing on the environment.

Unfaced Batts and Rolls


JM's Unfaced Insulation is a lightweight thermal and acoustical fiber glass insulation made of long, resilient glass fibers bonded with an acrylic thermosetting resin made without formaldehyde.

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