How is Insulation Installed in Existing Walls?

cellulose insulation in a bag with scoop
January 22, 2019

Well, the walls have already been built and the drywall is up. In fact, it has been for years. So it must be impossible to get in there and upgrade the insulation in your walls, right? Wrong. It may seem unlikely that there is an affordable and convenient way to upgrade your existing, outdated insulation in the walls of your home, but not when you go to the Wisconsin insulation experts! And what an integral step it is in keeping your home warm in the winter and cool in the summer.

What Kind Of Insulations Can Be Added to Existing Insulation?

We offer retrofit installation of loose fiberglass insulation, cellulose insulation, and spray foam. These are all installed by making small, circular holes in your existing drywall material. The size of these holes can be between a tiny 0.5” hole or larger 2” holes. These are easily covered up and repainted, so there is no evidence left behind. WHI Insulation will access your wall insulation from the exterior, unless your home’s exterior is brick, stucco, or Hardie Plank materials.

There are a few factors to take into account when determining which insulation material to use when upgrading your insulation:

  • Which walls are you looking to upgrade?

  • What is the existing insulation?

  • What are the goals for your new insulation?


Cellulose insulation is installed similarly to loose fiberglass, but is made of an environmentally friendly and cost effective material. Cellulose insulation is composed of the fibers from recycled newspaper and is treated for fire resistance, moisture and mold resistance, and to deter pests from infiltrating your walls.

Spray Foam

If you are looking to solve all of your insulation problems once and for all as well as seal up any and all leaks from room to room, then spray foam is the ticket. Spray foam is installed using multiple smaller 0.5” sized holes and will expand to fill all cracks and gaps. The air seal that spray foam provides eliminates any pollutants or allergens that infiltrate your home through your walls, provides a soundproof barrier, and will increase your overall indoor air quality.


If you currently have deteriorated fiberglass batt insulation in your walls, adding loose fiberglass insulation can safely be added through a 1.5–2” hole, blown in through a specialized hose. WHI Insulation will carefully determine the density at which your walls should be packed with fiberglass for optimum efficiency.

But be warned — if you have any existing fiberglass or cellulose insulation, it will need to be removed first before installing spray foam with the pros.

How To Know You’re In Need Of an Insulation Upgrade

Without X-ray vision, it is hard to know the state of your current insulation. WHI Insulation may not have X-ray glasses, but we have the next best thing: infrared thermal imaging with a professional energy audit!

An energy audit with a home performance expert will uncover any issues that are threatening your home comfort, what the causes are, as well as the home upgrades that will best solve the problem. Our infrared thermal cameras will locate where there are lapses in your outdated insulation, so we can make targeted insulation upgrades. Plus, with an energy audit, we can recommend any other services you can benefit from, so you can experience:

  • A more comfortable home

  • Reduced in heating and cooling costs

  • Healthier indoor air

  • Greater control over your home comfort

The Importance of Insulation in Wisconsin

The snowy and bitter winters are just one end of the pendulum swing here in Southeast Wisconsin. The other side of Wisconsin’s yearly weather is the hot and humid summer. Each end of the spectrum speaks to the importance of proper insulation!

Insulation in both your walls and your attic acts as a heat barrier, and that barrier works both ways. In the winter, insulation keeps the heat inside your home, so that your heating equipment doesn’t waste any excess energy. In the summer, insulation keeps the heat outside where it belongs — outside.

Are you concerned your existing insulation is leaving you both shivering and sweating at home throughout the year? Don’t waste any more time, and get a hold of the insulation experts at WHI Insulation today!

Worried your wall insulation has deteriorated beyond repair? There’s still hope! Upgrade your existing insulation with WHI Insulation! Call us at


or contact us today.

Don’t forget about what lies between your walls.

Upgrade your existing insulation!


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