When Replacing a Roof, Do You Need New Insulation?

January 25, 2023by Nick

One of the most common questions from people having their roofs replaced is whether they will need to replace their attic insulation, too. While it is entirely possible to replace a roof without making any changes to the insulation, there are a lot of benefits to getting both of these things done at the same time.

How to Know When Your Insulation Needs Replacing

So, as a homeowner, how do you know when your insulation is getting old or damaged? Most of the time, you will be able to tell by several factors.

If some rooms in your house never seem to get fully comfortable—they always stay a bit too hot or cold, never reaching the temperature you have set for the rest of the house—it could be a sign that your insulation isn’t at its best.

If your energy bills are unusually high, it means your heating or air conditioning could be having to work harder than usual to compensate for a flaw in the insulation. Older insulation can wither a bit and cause patchy spots where heat or cool air can escape through the attic.

If you go into your attic and notice that your insulation is damp, it could point toward a leak somewhere or a problem with ventilation. Both of these can cause serious problems with mold or decay in your home, and wet insulation no longer does its job of insulating the house.

Attic Insulation Requirements

More than 80% of homes in the NOVA region do not have the required amount of insulation, per local building code. VA Building Code recommends level R38 for attic insulation, which is approximately 14-15″ in depth. Having sufficient insulation is imperative for the overall energy efficiency of the home because ~35% of all heat loss (from the home) is lost through the roof or through the attic.

Replacing Your Roof and Insulation at the Same Time

It isn’t an absolute necessity to replace your insulation with your roof. If your insulation is reasonably new or a professional has confirmed that it is in good condition, you probably don’t need to worry about it. However, if you’ve noticed signs that your insulation is getting old or deteriorating, it can be a great idea to get it done while you get your roof replaced.

Benefits for You and Your Roofer

It’s pretty common knowledge that scheduling two home improvement projects will save you a lot of time and trouble in the long run. Most homeowners don’t love the sound of workers with power tools around the house, so scheduling two projects at once lets you shorten the time by having the projects overlap.

If you get your insulation swapped out while your roof is being replaced, work will be easier on the roofing crew because they don’t have to worry about coming back anytime soon. Since they’re already at your home with their tools and supplies, it simplifies their job and lets them use their time more effectively.

In addition, roofers can notice problems with your insulation while they’re working on your roof. This means they can point out places where your insulation might be damaged and help you to decide if you should move forward with replacing it.

Planning to Replace Your Insulation

If you decide that you do want to replace your insulation along with your roof, you should contact your roofing company as soon as possible and come up with a plan. Since there are different types of attic insulation to choose from, you will want to discuss the benefits and drawbacks of each one to most accurately decide which is best for your home.

What Type of Insulation?

There are several kinds of insulation that you can consider, but the most commonly used in residential projects are batts and blown insulation.

Batts are thick, flat sheets of insulation that are usually used between studs in a wall. It can be made of cotton or fiberglass and form a barrier around the edges in your roof or attic, but it tends to leave gaps that allow your indoor air to get out. In addition, batt insulation requires a lot more work and a specialized team to install.

Blown insulation is a loose material that gets blown into your attic using a machine with a hose attachment. Since it is in a small-particle form, it is much easier to install and thoroughly insulate even the most difficult-to-reach areas in your attic.

So, Do You Need to Replace Your Insulation with Your Roof?

The short answer is technically no. But if you know your insulation needs to be replaced, it can be a great plan to get it done at the same time as you get your roof replaced. It can save money and time for both you and your roofing company.

Looking to get your roof or insulation replaced? Contact us at St. Joseph’s Roofing to schedule a free estimate and get honest, straightforward consultation on your roofing project.

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