Here's How: Methods To Soundproof New or Old House

James Dulley on Nov 13, 2025

Dear James: Our older house is not very soundproof. Do you have tips for making it quieter both in this old house and for when we plan and design our future house? -- Steve R.

Dear Steve: Inadequate soundproofing, especially from outdoor noise, is a common problem with both old and new houses. Even if a new house is built to code, there can still be indoor noise issues because the quality of the workmanship is as important as the materials and designs used.

Before starting, it is helpful to understand how sound moves throughout your home and comes in from outdoors. Three key ways sound moves are by transmission through the wall and floor materials, by air leakage between rooms and from outdoors to indoors, and by loose vibrating materials.

Sound is transmitted when sound waves in the air contact a wall surface. This causes the wall surface to vibrate, and this movement is transferred through it to the wall on the other side. That wall begins to move, which causes the air to move and your ear picks it up as noise.

With air leakage noise, the vibrating air actually moves through a direct path from room to room or from outdoors. Opening your front door is an extreme example of this. Loose vibrating materials in the walls create noise when the two pieces hit or rub against each other.

Since you are moving out of your house in a few years, you will not want to make many expensive soundproofing improvements. Caulking any gaps between rooms and around windows and doors is probably the extent of the improvements you should make at this time.

Don't forget less obvious spots around baseboards, wall electrical outlets and heating ducts. These areas are often totally open from room to room for the free flow of the vibrating air.

When building your new home, you will have many more soundproofing options to consider. High-efficiency windows and an insulated front door will do a lot to block outdoor noise. Select windows with dense inert gas, such as argon or krypton, in the gap between the panes. These dense gases dramatically reduce outdoor noise transmission.

Insulating interior walls around problem rooms (bedrooms, work areas, home theaters, etc.) will help block certain types of noises. The following companies make special soundproofing materials and packages: Knauf Fiberglass, www.knaufnorthamerica.com -- QuietTherm; Johns Manville, www.jm.com -- ComfortTherm; and Owens Corning, www.owenscorning.com -- QuietZone.

One noise generator that is often overlooked is the plumbing system. Have your builder use piping larger than code requirements. This is particularly helpful in the bathrooms to reduce nighttime noise in an otherwise quiet house. Use special acoustical hangers when attaching the pipes to studs or joists. Also install cast-iron drain pipes instead of plastic.

Make the interior walls as strong and heavy as possible. The actual mass of the wall has a tremendous impact on the noise frequencies that readily pass through it. Using two rows of staggered two-by-fours on a two-by-six plate will block the direct sound transmission path from room to room.

Caulk every possible gap throughout the construction process. Once a wall or floor is completed, it is difficult to go back and thoroughly seal it. Consider installing insulated heating ductwork. It will lower your utility bills, too.

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Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, Ohio, 45244 or visit www.dulley.com. To find out more about James Dulley and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.