The Best Insulation for an Attic in A Meditteranean Climate

Selecting the best insulation for an attic is a little trickier than dressing for the weather. You want to make sure your home is kept cool in the summer while keeping your heating bills as low as possible during the winter.

However, unlike your outfits, you can’t change your insulation with the seasons. You want to make the best choice because it will need to last you a long time. By the time you read this article, you will know how to choose the most appropriate insulation for your attic.

Why You Need Insulation in Your Attic

You may not spend a lot of time in the attic, other than to store stuff you don’t otherwise know what to do with. However, you’ve spent enough time in there to know that it gets unbearably hot.

Almost 90% of homes in the U.S. are not well insulated. An attic gets much hotter than the outside temperature because of radiant heat.

What is Radiant Heat?

Building materials in your attic absorb and re-emit stored heat. This stored heat radiates into the already warm environment, making it even more uncomfortable.

The bad news is that radiant heat can transfer into the living areas of your home through the ceiling. The reverse is true in winter.

Heaters and furnaces need to work overtime to replace the thermal energy that is lost through the ceiling into the attic. In short, insulation will make your life more comfortable and will save you money on your energy bills.

The money you can save is not trivial. The average home can increase energy efficiency by more than 50% when it’s properly insulated, which equates to a significant savings on your household expenses.

How to Select the Best Insulation for Your Attic

Now that you know that insulating your attic will make your life more comfortable and save you money, it’s time to explore the different insulation types and learn which one will provide the most value.

Blown-In Insulation

Blown-in insulation, which can be made from loose materials like loose-fill fiberglass, rock wool, or cellulose, is an efficient way to insulate an attic. Insulation technicians use a large hose to blow the insulation into your attic, which will settle into a level surface all across the attic.

It’s more expensive, but there is a payoff in efficiency. All air leaks are sealed, and every nook and cranny of your attic is covered with insulating material. If you have a cramped attic with hard to reach spots that are almost impossible to cover with other insulation types, blown-in insulation is an excellent option.

The airtight seal helps to keep condensation and moisture out of your home and prevents rotting, as well as mold and mildew outbreaks.

Fiberglass Batting

Fiberglass batting is a big favorite around the San Francisco and Contra Cosa areas. Installation is straightforward, and it’s waterproof and fire retardant. The majority of homes are insulated with fiberglass batts because it’s one of the cheapest and easiest things to do yourself. However, professional installation is recommended because it ensures your attic insulation is as efficient as possible.

Blown-In Versus Rolled Material: Which is Better?

Rolled material is popular because it’s cheaper and doesn’t require specialised tools for installation. Ensuring rolled material fits neatly around electrical conduits, plumbing, and piping requires a lot of manual labor.

It’s easy to see why rolled insulation is the preferred choice during construction. Unfortunately, installing it in an existing property usually means there will be gaps and voids that threaten efficiency. Naturally, fiberglass batts are similarly problematic.

Blown-in insulation material for your attic creates a “monolithic fill,” a fancy way of saying the insulation will create an airtight blanket over your attic floor.

Fiberglass Insulation versus Cellulose Insulation: Which is Better?

As new building codes and regulations eliminate insulation materials that are inefficient, don’t work, or are downright dangerous, property owners are left with two main choices: cellulose or fiberglass.

Cellulose and fiberglass are both excellent insulators, but there is some confusion when talking about blown-in insulation. Cellulose is only available as a blown-in material, while fiberglass is available as both batts and blown-in.

Fiberglass and Cellulose Pros and Cons

Fiberglass insulation is exceptional for many reasons, including:

• It’s created from recyled materials
• It’ Readily available and affordable
• It’s an efficient thermal insulator
• It’s Mold and mildew resistant
• It’s available in a range of R-Values (measure of heat resistance)
• Flame retardant

The “R” in R-value stands for resistance and measures how well insulation can resist heat. You will need around 12 inches of fiberglass batt insulation to achieve an R-value of 30. Fiberglass is quick and easy to install and can be done as a DIY project.

There are just as many good reasons to consider cellulose insulation, including:

• It’s also created from recycled materials (magazines, cardboard, newspapers)
• It won’t make you itchy
• Available in a range of R-values
• Insect resistant
• Mildew and mold resisant
• Excellent soundproofing
• Fire-retardant

Cellulose is a more efficient insulator as it takes just 8.1 inches to gain an R-value of 30. However, fiberglass is much lighter and easier to use as a blown-in insulation that will cover every gap.

Cellulose can settle and pack down over time, which will reduce its R-value. While fiberglass can pack down, it takes much longer, which is why 30+ years of warranty is not uncommon.

Fiberlgass and Cellulose Safety Considerations

Fiberglass uses natural, recycled products like sand. Cellulose is made from recycled newspaper, cardboard, and magazines and contains artificial chemicals to bind all the particles together. Machines used to filter the cellulose material aren’t 100% efficient, so parts of old plastic cups, credit cards, and other bits and pieces get shredded in the machine.

The resulting product is then stabilized with boric acid and other chemicals to create a pest-resistant and fire-retardant material. Unfortunately, cellulose degrades and releases airborne contaminants over time. These small particles filter through the electrical ventilation to compromise the quality of your air.

Only natural adhesives and binders are used in fiberglass, making it the safest long-term insulation solution.

Would you like to know more about choosing the best attic insulation or replacing existing insulation? Check out Attic Pros. We offer professional installation as well as rodent eradiaction and prevention, guaranteeing you will get the most out of your attic insulation.