Cellulose Insulation / 08.31.17 Your guide to installing cellulose insulation for sidewall retrofit applications

Pop quiz — did you know that many homes built before 1970 have zero insulation in their wall cavities? That’s major energy loss right there. Even in new homes, sidewall cavities are the second-biggest area of heat escape. For pros and DIYers who are ready to get down to business, follow this guide for installing Greenfiber Blow-in Insulation in sidewall retrofit applications.

Sidewall Preparation

  • Check the interiors and exteriors of the home, under sinks and around plumbing fixtures for any cracks and holes, and make sure to seal them with foam or caulk.

  • Remember to avoid installing insulation in stud runs where there are heat-producing devices, such as a fireplace, recessed lights or a chimney.

  • Do not install insulation in any structure that uses knob and tube wiring.

  • Block off tops and bottoms of areas with balloon construction (areas where wall cavities are open from the attic to the basement or crawl space) before blowing.

Blower Machine Guidelines

  • Place the blower machine on level ground, close to your work space and electrical outlets.

  • Use the shortest length of blowing hose possible, and keep the hose straight.

  • Put a tarp underneath the blower machine for easy cleanup. The tarp will also keep foreign objects from getting into the hopper.

  • There are several types of blower machines with adjustable airflows. Double check the operating instructions before use.

Drilling Instructions

  • Check that the drill bit size matches the plugs and reducer size (most are 1 inch) before drilling.

  • Remove siding when drilling holes through the sheathing, or drill holes directly through the wood siding.

  • For single-story homes, drill a hole between two studs, about 3 feet above the bottom of the wall. Drill a second hole about 1 foot below the top of the wall in the same stud cavity. For multi-story homes, repeat these steps for each floor. Walls taller than 10 feet should have holes drilled every 5 feet. The top hole should be about 1 foot from the top of the wall.

  • Avoid drilling into areas of cold air returns.

  • Probe all cavities with a plumb bob to determine the depth of the cavity, and find any difficult areas that may alter the flow of loose-fill cellulose insulation.

  • Older homes may have corners with diagonal bracing. Check corners of walls to determine if your house has this type of framing. If so, drill additional holes in the corners.

Installation Instructions

  • Insert the nozzle into the bottom hole first, and turn on the blower machine. The blower will start to strain when the cavity is filled. Check to see that the cavity is full before filling the next hole. Be sure to always start by filling the bottom hole.

  • After filling each hole, check the end of the nozzle to make sure there is no material blocking the opening. A wire coat hanger or screwdriver can be used to unclog the nozzle. If this doesn’t work, remove the nozzle from the hose and clear the blocked material by closing the gate and blowing excess material into the trash. Reattach the nozzle once the hose is empty.

  • Place plugs into the holes after the cavities have been filled. Recess plugs 1/16 inch to 1/8 inch past the face of the plaster, drywall or siding. Cover the plugs with interior or exterior spackle as needed.

  • When you are done with the project, empty the machine of all insulation by blowing excess material into the trash.

Wall Kit Materials

  • 1-inch wall nozzle

  • 1-inch plastic, wood or foam plugs

  • Wall spackle (interior or exterior)

Recommended Tools for Installation

  • Stud finder

  • Putty knife

  • Utility knife

  • Drill

  • Two 1-inch drill bits

  • Dust mask

  • Eye protection

  • Duct tape

Find more information on installation instructions for sidewall retrofit applications here.