Taking steps to improve the soundproofing in your home's existing interior walls can help reduce potentially harmful noise pollution. The U.S. Environmental Protection Agency cites studies that have shown direct links between noise and health problems such as high blood pressure, stress-related illnesses, sleep disruption and loss of productivity. Create a quieter, more tranquil home environment by increasing the soundproofing of your existing walls.

Insulation

Blowing insulation into the interior spaces of existing walls can make them more soundproof, reducing the amount of noise seeping into a room. Insulation is blown into an existing wall with specialized hoses, pumps and machines through holes that have been drilled into the wall. Fiberglass insulation tends to dry out quickly, making it ideal for wetter geographic areas that generate more moisture. Cellulose insulation is environmentally safe and nontoxic. It's often made from shredded, recycled newsprint that's been treated with a fire retardant.

Drywall

Add a second layer of drywall over existing interior walls to increase the thickness and weight of the wall. Heavier walls with greater mass are typically more soundproof than their thin counterparts. Add a layer of Green Glue damping compound between the two drywall layers to create an even greater soundproofing barrier. Green Glue is a material used as a constrained membrane that converts sound energy into heat.

Paint

Apply specially formulated acoustical paint to your interior walls to reduce noise by up to 30 percent. Acoustical paint is created with sound-absorbing resins, fillers and hollow ceramic microspheres that can improve the soundproofing of your walls. Apply paint to your walls with a paint roller for the larger areas and angled paintbrushes for hard-to-reach corners and edges. Acoustical paint dries quickly and has superior insulating and sound-dampening characteristics. Apply two coats of paint for optimal results.

Wallpaper