Blowing insulation into existing walls

Blowing insulation into existing walls. Insulating the home exterior and interior walls is a modern technique to prevent heat and energy loss.

If your home is too old, like it is thirty to 40 years old, then it might not be insulated because it was not a trend at that time to insulate the home walls.

Nowadays, builders insulate existing exterior walls from the outside or inner side to protect the heat loss.

If you try to insulate the walls from outside of the home wall, you need to remove side panels to create big holes by covering the top wall spaces.

However, if you want to insulate your old home because its exterior walls are not insulated, use the blown-in insulation technique.

But the question is it possible to insulate the existing walls without detaching them? Keep reading this article to learn how blown-in insulation is helpful to better home conditions and decrease energy loss.

Blowing insulation into existing walls

It’s a much more difficult task to insulate the wall than in an attic because you need to hide the insulation materials inside the walls. After all, it looks awkward if you do not insulate the exterior and interior walls properly.

It’s very costly to detach all the wall coverings, so you can easily make a small hole in the exterior and interior wall to blown-in insulation.

If you are making a new home, then blowing insulation into new walls is unsuitable because you can insulate the walls during the home’s construction.

If your home is old and you want to reinsulate, make a large home with the help of a big saw. Although it makes large dust and mess, you have no choice but to cover everything.

Cover all things

cover all things

Blowing insulation in the existing walls creates a lot of dust and mess due to drilling in the brick walls, so before you start your work, it’s important to cover all the things with big clothes to save them from dust.

If you have any electrical appliances like a television, refrigerator, etc., shift them into another room to protect them from dust.

Protective gear

protective gear

You already know that blowing insulation in the wall is a messy task, and it creates a lot of dust and dirt, so your priority must be to protect your eyes and skin from the mess.

Wear gloves, a face mask, and glasses on your eyes for self-protection. It’s better to wear old clothes during work because the clothes get dirty.

Locate the place

The first and most important thing for perfect blown-in insulation is determining where you install the insulation, whether you want to install the insulation from the inner side of the walls or insulate from the outside of the wall because it depends upon the construction of the wall.

Use a stud finder

use a stud finder

Take a stud finder to find all the studs in the wall. After finding the studs in the wall, now blow a hole between two studs with the help of a hole saw.

Ensure the distance between each hole must be 2 inches and near the wall top.

If the bricks are installed in the wall in a horizontal shape, you must create a second drill between the center of two studs.

It is important because studs are positioned after 16 inches, so drilling to insert insulation must be constructed at the same distance to fill one cavity.

Fill the cavities

fill the cavities

After drilling all the holes in the walls, now fill all the cavities in the holes with blown insulation for proper home energy protection.

Ensure no cavity holes remain in the wall because it will emit energy. Always follow the manufacturer’s suggestion for proper and dense insulation of exterior walls.

Once you have ended filling all the cavities, verify all the cavities are filled with insulating material or that some cavities are escaped by mistake.

Patch walls

patch walls

When you have done your insulation, now your challenge is to repair and paint over the holes so that it does not look awkward and gives the same look as before blowing insulation.

Clean all the dust and mess from the surrounding after completing your work.

Pros and cons of blown-in insulation

There are some advantages and disadvantages of blowing insulation in the exterior walls, so you can make an idea of whether blowing insulation is suitable for your home or not.

pros and cons of blown in insulation

  • Pros

The first and foremost advantage of blowing insulation is it saves the energy bills in the home because it protects the home from energy loss.

For example, if you have turned on the air conditioner to cool the room in the summer season, then insulation walls will not escape the energy from the room, and you can turn off the ac unit after some time to save the energy bill.

The insulating material has fire-resistant power to protect the home from fire danger. Unfortunately, if your home gets fire, it slows down the fire spread.

It’s very easy to install the blowing installing because you can also blow material in the small holes, gaps, and hidden places.

  • Cons

Besides many advantages, there are also some disadvantages of insulating the exterior walls. Like if you use the insulating material on the home’s exterior walls where it is appropriate to blow insulation because it can create can damp issues that are difficult to fix.

If it rains outside, exterior walls get wet and eventually wet the insulation material. Wet insulating material becomes worthless and dangerous because damp patches inside the house do not give a pleasant look to watch.

It becomes difficult and costly to replace the damp insulation because you require professionals to pull out the wet insulation from all cavity holes and then reinstall the blowing insulation.


If you want to insulate the home exterior and interior walls, blowing insulation is the best and quick technique because you can do it quickly.

Blowing insulation is not only done on the wall, but you can also install it on attics and under the floor to save energy.

Although it has pros and cons, like it is easy to install and does not allow the energy to escape inside the home, you may also face damp walls due to rain if you insulate the home’s exterior walls.

Nowadays, people insulate the walls during the construction of a new home but if you have a 50-year-old house, hire a skilled professional to insulate the walls.

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