What if you already have insulation?

Attic

Nearly all homes have attic insulation as a small amount was typically included when the house was built.

In addition to the original insulation 30-50% of the older homes in Orange County have had additional insulation (either cellulose or, more commonly, fiberglass) blown in at some point. However, unless the insulation was blown in after 1998 the material was most likely only blown to the then recommended R-19.

The Department of Energy has since completed a study recommending a minimum R-Value in Southern CA of R-38. So, unless your attic was blown since 1998 odds are your insulation is still only half insulated at best.

Also, most installers do not include cathedral ceilings so you most likely have only the original insulation in those cavities.

Walls

If your attic was insulated by a previous owner they most likely left the exterior walls untouched, as very few insulation companies are capable of wall restoration.

If you like in a pre 1975 home and your home was built with wall insulation it was most likely a very small fiberglass batt. (There was no requirement for wall insulation prior to 1975 but some home builders offered “wall insulation” as an optional upgrade.

Since there was no minimum, however, builders used very thin, inexpensive batts which did not fill the entire cavity.)

While obviously preferable to having walls which are completely imply, these thin batts allow a tremendous amount of both radiant heat and cold air to pass through the exterior walls and it is recommended that you have the walls filled completely with blown insulation

How Insulation is Installed?

Loose-Fill (Blown-in)

Using a long hose that’s connected to a blowing machine, insulation is directed into a wall cavity or attic, filing the cavity or blanketing the space.

Cellulose insulation is blown to either 8.5″ depth (R-30) or 5″ depth (R-19) depending on your existing level of insulation.

A significant advantage of blown-in insulation over batts is that it completely fills the wall cavities, particularly around electrical outlets and other penetrations, blocking air movement through the wall.

Once wall cavities have been entirely filled the vapor barrier is sealed with a Styrofoam plug and one of our restoration specialists applies two coats of texture (wood or stucco) and custom mixes several gallons of paint to match the exterior of the home and completely hide the holes made for the insulation.

Batt Insulation (Rolls)


Fiberglass batts are most commonly used in new construction, including residential room additions.

Any room additions built after 1975 have fully insulated attics and walls, as mandated by CA state code. Fiberglass batts come in 24″ & 16″ wide rolls and are snuggly fit between ceiling joists and exterior wall studs.

Most homes constructed before 1975 had very thin (R-6 to R-8) Fiberglass Batts installed at the time of construction. Homeowners have the option of having 10″ (R-30) batts installed in their attic, on top of the original, existing ones but Guardian Insulation recommends blown insulation for attics, as they more effectively block both heat and sound.

Exterior walls can only be insulated with batt insulation if the drywall has been removed and is seldom economically practical.

What “R-Value” Means?

R-value is a measure of resistance to heat flow through a given thickness of material. In theory, the higher the R-value, the greater that resistance. That’s fine as far as it goes.

Unfortunately, R-Value has taken hold in the consumer’s mind as a universal method for comparing insulations – the higher the R-Value, the better the insulation, end of story. But all R-Values are not created equal, because they measure only one of the factors that determine how insulation will perform in the real world.

Insulation is, first and foremost, meant to stop the movement of heat. The problem with using R-Value as the sole yardstick of an insulation’s effectiveness is that heat moves in and out of your home or commercial building in four ways: by conduction (which R-Value measures), and by convection, radiation and air infiltration (none of which R-Value measures). But let’s stick with the concept of R-Value for the moment.

The R-Values of insulation materials are measured in a lab. That would work great – if your home were inside a lab! But your home was built outdoors, and that means there are other factors like wind, humidity, and temperature changes in play. These factors create pressure differences between the interior and the exterior of the building due to things like hot air rising, wind, and mechanical systems forcing air through every tiny little opening and making its way to the interior or exterior, or to unconditioned areas of the building like attics, basements and crawl spaces.

Your home may look solid, but there are thousands of tiny gaps, cracks and penetrations between building materials. For example, if you apply the air pressure of a 20 MPH wind on a 20 deg. F day to a building, the typical R-19, fiberglass insulated wall often performs no better than the wood studs (R-6) because of air infiltration, with heat being transported around (bypassing) the fiberglass batts through convection. In very low density materials like loose blown fiberglass, heat will actually radiate right through the insulation, and this, along with convection, significantly reduces fiberglass’ installed performance and your comfort.

A superior insulation system will have good R-Value (prevent heat loss via conduction), will be pneumatically or spray applied, fully filling the building cavity (prevent heat loss via convection), and will be densely packed (prevent heat loss via air infiltration and radiation). Fiberglass meets the first criteria, but not the other three. Cellulose meets all four of these critical performance criteria!

In addition, you want your insulation to do more than just insulate. Besides insulating, cellulose can help prevent the spread of flames in the event of a fire and blocks the transmission of sound much more effectively than fiberglass. The insulation in your walls, ceilings, attic, etc., has a lot of jobs to do besides insulating – and cellulose is up to all those jobs!

Incentives for installing insulation?

In Orange County, residents are entitled to receive Federal tax credits, rebates from Southern California Gas and credits from Southern California Edison.

Several factors go into determining the amount of the credits including existing level of insulation, total square footage to be insulated, cost of insulation and size of air conditioning unit. Your Guardian Insulation field technician will give you precise number for these programs, in addition to a projection of savings

Best insulation for the Environment?

Cellulose insulation is made from at least 80% post-consumer recycled newspapers and is the highest in the industry.

Not only does this divert waste from landfills but it also takes minimal energy to convert the newspaper to high quality insulation.

It is estimated that if all the newspapers currently going to landfills was converted to Cellulose insulation it would save 7,030,000 tons of CO2 equivalents.

That’s the same as taking all the cars off the road in New Mexico and Arizona every year.

“R-value for R-value” Fiberglass uses approximately 10 times more energy than Cellulose insulation to produce and transport while foam products, derived from petroleum, use even more. In addition, neither of these products is recyclable.

More and more consumers want to know how green the materials that go into their homes are.

That’s good news for our industry, because cellulose insulation is the Greenest Of The Green.

Do I Have To Take Out Insulation?

Most likely not. Adding more insulation has a cumulative impact on the overall R-value.

The problem with older homes is not so much that their insulation is “bad,” there’s simply not enough of it.

In the attic, insulation typically only needs to be removed if there has been an infestation and removal is recommended for health reasons.

We typically just blow in new insulation on top of the existing insulation and improve the overall quality and R-value.