---
title: Why You Should Remove Existing Insulation When Insulating Your Attic
description: Do you have to remove the existing insulation in your attic? Find out if you can just add more insulation to boost its performance.
image: https://scsfoam.com/hubfs/Article%20Title%20Images/Why%20You%20Should%20Remove%20Existing%20Insulation%20When%20Insulating%20Your%20Attic.jpg
---

[Skip to main content](https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic#maincontent)

[(717) 895-3498](tel:7178953498)

[![South Central Services Insulation](https://scsfoam.com/hs-fs/hubfs/branding/Website%20Logo%20Classic.png?width=900&height=300&name=Website%20Logo%20Classic.png) ![South Central Services Insulation](https://scsfoam.com/hs-fs/hubfs/branding/Website%20Logo%20White.png?width=900&height=300&name=Website%20Logo%20White.png)](https://scsfoam.com/)

[Our Service Areas](https://scsfoam.com/our-services-areas)

 Pricing

- [Our Rates](https://scsfoam.com/our-rates)
- [Calculators](https://scsfoam.com/pricing-calculators)
- [Financing](https://scsfoam.com/financing-options/)
- [Rebates](https://scsfoam.com/rebates)

[Our Team](https://scsfoam.com/our-team)

 Services

- Residential Insulation 
    - [Attic Insulation](https://scsfoam.com/attic-insulation)
    - [Basement Insulation](https://scsfoam.com/basement-insulation)
    - [Crawl Space Repair](https://scsfoam.com/crawl-space-encapsulation)
- [Commercial Spray Foam](https://scsfoam.com/commercial-spray-foam/)
- [New Construction Insulation](https://scsfoam.com/new-home-construction-insulation/)
- [Pole Building Insulation](https://scsfoam.com/pole-building-insulation)
- [Air-Sealing](https://scsfoam.com/air-sealing)
- [Blower Door Tests](https://scsfoam.com/blower-door-tests)

[Our Products](https://scsfoam.com/our-products)

 Learning Center

- [Learning Center](https://scsfoam.com/learning-center)
- [Downloadable Resources](https://scsfoam.com/downloadable-resources)
- [FAQ](https://scsfoam.com/faq/)

Open Search 

[Get A Quote](https://scsfoam.com/contact/)

 Search for topics or resources

 Enter your search below and hit enter or click the search icon.

Search for topics or resources

Close Search

[Our Service Areas](https://scsfoam.com/our-services-areas)

 Pricing

 Pricing

[Our Rates](https://scsfoam.com/our-rates)

[Calculators](https://scsfoam.com/pricing-calculators)

[Financing](https://scsfoam.com/financing-options/)

[Rebates](https://scsfoam.com/rebates)

[Our Team](https://scsfoam.com/our-team)

 Services

 Services

 Residential Insulation

 Residential Insulation

[Attic Insulation](https://scsfoam.com/attic-insulation)

[Basement Insulation](https://scsfoam.com/basement-insulation)

[Crawl Space Repair](https://scsfoam.com/crawl-space-encapsulation)

[Commercial Spray Foam](https://scsfoam.com/commercial-spray-foam/)

[New Construction Insulation](https://scsfoam.com/new-home-construction-insulation/)

[Pole Building Insulation](https://scsfoam.com/pole-building-insulation)

[Air-Sealing](https://scsfoam.com/air-sealing)

[Blower Door Tests](https://scsfoam.com/blower-door-tests)

[Our Products](https://scsfoam.com/our-products)

 Learning Center

 Learning Center

[Learning Center](https://scsfoam.com/learning-center)

[Downloadable Resources](https://scsfoam.com/downloadable-resources)

[FAQ](https://scsfoam.com/faq/)

[(717) 895-3498](tel:7178953498)

[Get A Quote](https://scsfoam.com/contact/)

[«  View All Posts](https://scsfoam.com/blog)

# Why You Should Remove Existing Insulation When Insulating Your Attic

 December 18th, 2024

 4 min read

 By [Kilian Agha](https://scsfoam.com/blog/author/kilian-agha)

![](https://scsfoam.com/hubfs/Article%20Title%20Images/Why%20You%20Should%20Remove%20Existing%20Insulation%20When%20Insulating%20Your%20Attic.jpg)

If you're adding new insulation to your attic, you need to remove any existing insulation upstairs. It might feel counterintuitive to take away the insulation you already have. However, insulation removal is a vital step in this process. Not removing existing insulation could detrimentally impact the performance of the new insulation you're purchasing.

South Central Services has insulated hundreds of attics in and around Mercersburg, Pennsylvania. There are four reasons why existing insulation must be removed. By the end of this article, you'll know why you should get the old insulation out of your attic.

> Don't have time to read right now? Check out [everything you need to know at a glance](https://scsfoam.com/hubfs/At%20A%20Glance/Why%20You%20Should%20Remove%20Existing%20Insulation%20When%20Insulating%20Your%20Attic.pdf).

## 1. Existing Attic Insulation Can Be Dirty Or Home To Pests.

The most common attic insulations are fiberglass batt and blown-in products. Both types of insulation can be a home for rodents. Pests will climb into batt insulation to create a nest. Blown-in insulation can also be a nesting material for rodents if rats or mice can get into your attic.

Inevitably, when rodents are living in your attic insulation, they will soil it with their droppings. Even if pest control measures are taken, and you no longer have any rodent infestations, their droppings will still be contaminating the insulation.

![A spray foam installer from South Central Services disposing of old fiberglass insulation from an attic in Chambersburg, PA.](https://scsfoam.com/hs-fs/hubfs/assets/images/Existing%20Insulation%20Removed%20From%20Attic.jpg?width=600&height=400&name=Existing%20Insulation%20Removed%20From%20Attic.jpg)

> You do not want rodents or rodent droppings in your home. This is a health hazard. Covering up the nests or droppings with new insulation does not make the situation safe. It would also be a danger for whoever installs the insulation.

## 2. Existing Attic Insulation May Not Be Installed Properly.

If you've never had any issues with rodents, you still need to remove the existing insulation upstairs. The fact that you're investing in new insulation indicates that your current insulation isn't working.

Hypothetically, you could top off your existing insulation with new. Topping off insulation is actually a [common method used for blown-in products](https://scsfoam.com/blog/does-blown-in-insulation-settle) when the initial insulation has settled enough to impact the R-value. However, that method only applies when the insulation was functioning correctly the first time.

![An attic in Smithsburg, MD, insulated with blown-in cellulose on the attic floor.](https://scsfoam.com/hs-fs/hubfs/Service%20Area%20Pages/Smithsburg%20MD%20Blown-In%20(3).jpg?width=533&height=400&name=Smithsburg%20MD%20Blown-In%20(3).jpg)

Has your attic insulation ever made a significant dent in your energy costs or the comfort of your home? Topping off the insulation won't make these changes. There are likely issues with how the insulation was initially installed. To address these issues, the insulation must be removed.

Attic insulation is meant to decrease energy waste and lower energy bills. We don't insulate our homes just to insulate them but to make them more energy efficient and comfortable. If the insulation wasn't installed correctly, your energy costs will never decrease until the insulation is fixed.

> It could be that baffles have been installed incorrectly or that the insulation is not contained in the attic properly. Any number of roof or attic issues could be at play. An insulation contractor can address these issues by starting with a clean slate.

It is best to cut your losses now and insulate correctly. You will waste more money if you install more insulation on top of the existing insulation.

## 3. Existing Attic Insulation Blocks Air-Sealing Measures.

No matter what insulation you choose for your attic, you need to [air-seal](https://scsfoam.com/blog/should-i-air-seal-my-attic). Even if you select budget-friendly insulation like [blown-in cellulose](https://scsfoam.com/blog/blown-in-cellulose-pros-cons), air-sealing is necessary to maximize its performance. Budget-friendly insulations cannot air-seal on their own, which results in energy waste through air leakage.

![An attic floor with wires, air-sealed and prepped for blown-in insulation using can foam.](https://scsfoam.com/hs-fs/hubfs/Article%20Graphics/7.30.24%20Blown-in%20prep%20(T).jpg?width=300&height=400&name=7.30.24%20Blown-in%20prep%20(T).jpg)An insulation contractor cannot install an air-seal with existing insulation in the way. [Air-sealing your attic floor](https://scsfoam.com/blog/what-is-attic-air-sealing) means identifying gaps, holes, cracks, and other air leaks. Once these areas are addressed, heat can no longer escape at random through air leakage.

If your current insulation isn't cutting it, you want to invest in something that will make an improvement. A budget-friendly attic insulation paired with an airtight seal is the most affordable way to lower energy costs.

Without removing that existing insulation, the air leaks in the attic can never be identified. The investment in new insulation won't offer much of an improvement.

## 4. Existing Attic Insulation Prevents Spray Foam From Adhering.

If you're less concerned about budget, you may want to invest in the best-performing insulation for your attic. Premium insulation like spray foam will deliver the most improvement. However, [spray foam cannot be installed where existing insulation is](https://scsfoam.com/blog/does-attic-insulation-need-removed-before-installing-spray-foam).

> Spray foam insulation requires a clean surface to adhere to. It cannot be installed on top of batts or blown-in insulation.

The difference between spray foam and more budget-friendly insulations is the ability to air-seal. While batts and blown-in products need a separate air-sealing product, spray foam insulates and air-seals on its own.

When spray foam adheres and expands, it sticks like glue to the surface and seals any leaks in the attic floor. It also delivers a high R-value to help combat conductive heat transfer.

> [          View this post on Instagram                      ](https://www.instagram.com/reel/C-LGewmPOm5/?utm_source=ig_embed&utm_campaign=loading)
> 
> [A post shared by South Central Services Insulation (@scsfoam)](https://www.instagram.com/reel/C-LGewmPOm5/?utm_source=ig_embed&utm_campaign=loading)

If you have the money to invest in spray foam insulation for your attic, removing existing insulation is a given. It can be frustrating to have existing insulation removed. Sometimes, it feels like your previous investment is being thrown away. However, if you won't get rid of the insulation that isn't working, you would be making an investment that would have to be thrown away.

> [The goal of new insulation is an improvement.](https://scsfoam.com/blog/will-attic-insulation-make-a-difference) Old insulation has to be replaced if any improvement is going to be seen.

## The Bottom Line About Removing Existing Attic Insulation

You must remove existing attic insulation when you have new insulation installed. Existing insulation can hide rodent nests, droppings, mold, mildew, or other moisture issues. The insulation likely was never installed correctly in the first place, and it covers up air leaks in the attic floor.

As long as you're replacing your insulation upstairs, it's best to make the most of that investment. By removing existing insulation and air-sealing your attic floor, you'll have lower energy bills, better air quality, and a more comfortable home.

Now that you understand why existing attic insulation must be removed before adding new, your next step is to:

- [Learn why you should air-seal your attic](https://scsfoam.com/blog/should-i-air-seal-my-attic)
- [Compare blown-in cellulose insulation with spray foam](https://scsfoam.com/blog/spray-foam-insulation-vs-blown-in-cellulose)
- [Estimate the cost of blown-in insulation with an airtight seal](https://scsfoam.com/blog/blown-in-attic-insulation-cost)

[![DOWNLOAD MY GUIDE](https://no-cache.hubspot.com/cta/default/39735758/interactive-183861152821.png)](https://scsfoam.com/hs/cta/wi/redirect?encryptedPayload=AVxigLLU2WDFPujATtt0t1ogqoxxUwXhD4KwbABCQXxbvfhW7IaKSAl5snPbjHzR9YV22Y4tp4zolWdt0HyXasBydSbwKkF2MGuCnaiutTVbujP5VuxEG%2Fn4QPCmO1bY0apjWkWhKi5x5EjPrCqAx3WutEoy2BM%2BT1yP4TJKilxKEQmkS1roZuL%2BiwGPHpFXNeU1XcoaSjjM6iI8Aw%3D%3D&webInteractiveContentId=183861152821&portalId=39735758)

*Disclaimer: While we strive to publish information accurate to building science, local building codes and standards supersede our recommendations.*

<https://scsfoam.com/blog/author/kilian-agha>

[Kilian Agha](https://scsfoam.com/blog/author/kilian-agha)

Kilian has co-owned and operated South Central Services for 8 years. He is passionate about community involvement. In his spare time, he enjoys being with his family, playing ice hockey, and going fishing with friends.

 Topics:

[Attic](https://scsfoam.com/blog/topic/attic)

[Air-Sealing](https://scsfoam.com/blog/topic/air-sealing)

 Don't forget to share this post:

<https://www.facebook.com/sharer/sharer.php?u=https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic> <https://www.linkedin.com/shareArticle?url=https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic&title=Why+You+Should+Remove+Existing+Insulation+When+Insulating+Your+Attic&summary=Do+you+have+to+remove+the+existing+insulation+in+your+attic%3F+Find+out+if+you+can+just+add+more+insulation+to+boost+its+performance.> <https://twitter.com/intent/tweet?text=Why+You+Should+Remove+Existing+Insulation+When+Insulating+Your+Attic&url=https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic> <https://pinterest.com/pin/create/button/?url=https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic&media=&description=Do+you+have+to+remove+the+existing+insulation+in+your+attic%3F+Find+out+if+you+can+just+add+more+insulation+to+boost+its+performance.>

## Related Articles

### [How To Seal Attic Air Leaks June 11th, 2025|3 min read](https://scsfoam.com/blog/how-to-seal-attic-air-leaks)

### [Do Attics Need Ventilation? May 19th, 2025|3 min read](https://scsfoam.com/blog/do-attics-need-ventilation)

### [Can You Air-Seal Your Attic Yourself? May 9th, 2025|4 min read](https://scsfoam.com/blog/can-you-air-seal-your-attic-yourself)

### [Will Spray Foam Rot My Roof? April 30th, 2025|4 min read](https://scsfoam.com/blog/will-spray-foam-rot-my-roof)

### [What Does Air-Sealing An Attic Mean? April 28th, 2025|3 min read](https://scsfoam.com/blog/what-is-attic-air-sealing)

### [How Much Does Air-Sealing An Attic Cost? April 11th, 2025|3 min read](https://scsfoam.com/blog/attic-floor-air-sealing-cost)

### [Will Adding Attic Insulation Make A Difference? March 26th, 2025|4 min read](https://scsfoam.com/blog/will-attic-insulation-make-a-difference)

### [Is Spray Foam Insulation Bad For Your Roof? January 22nd, 2025|3 min read](https://scsfoam.com/blog/is-spray-foam-bad-for-your-roof)

### [Which Blown-In Insulation Is Best For Attics? September 4th, 2024|3 min read](https://scsfoam.com/blog/best-blown-in-attic-insulation)

### [Should I Air-Seal My Attic? August 23rd, 2024|7 min read](https://scsfoam.com/blog/should-i-air-seal-my-attic)

### [Can You Spray Foam Insulation On Ductwork? August 14th, 2024|2 min read](https://scsfoam.com/blog/can-you-spray-foam-on-ductwork)

### [Does Blown-In Insulation Settle? July 22nd, 2024|3 min read](https://scsfoam.com/blog/does-blown-in-insulation-settle)

### [Pros And Cons Of Blown-In Cellulose July 17th, 2024|5 min read](https://scsfoam.com/blog/blown-in-cellulose-pros-cons)

### [How Much Does Attic Insulation Cost? June 19th, 2024|8 min read](https://scsfoam.com/blog/how-much-does-attic-insulation-cost)

### [Does Attic Insulation Need To Be Removed Before Installing Spray Foam? February 7th, 2024|3 min read](https://scsfoam.com/blog/does-attic-insulation-need-removed-before-installing-spray-foam)

### [Should I Insulate My Attic Floor Or Ceiling? January 8th, 2024|4 min read](https://scsfoam.com/blog/insulate-attic-floor-or-ceiling)

### [Spray Foaming Your Attic with South Central Services: What To Expect November 6th, 2023|3 min read](https://scsfoam.com/blog/attic-spray-foam-with-south-central-services)

### [Why Choose South Central Services To Insulate Your Attic October 25th, 2023|4 min read](https://scsfoam.com/blog/insulate-your-attic-with-south-central-services)

### [Cost Of Attic Spray Foam Insulation In Pennsylvania October 16th, 2023|5 min read](https://scsfoam.com/blog/spray-foam-insulation-cost-attic-pa)

### [How To Insulate An Attic With Spray Foam October 11th, 2023|6 min read](https://scsfoam.com/blog/spray-foam-attic-insulation-how-to)

### [Does My Attic Need Insulation? September 13th, 2023|4 min read](https://scsfoam.com/blog/does-my-attic-need-insulation)

### [Benefits Of Insulating Your Attic With Spray Foam September 8th, 2023|4 min read](https://scsfoam.com/blog/attic-spray-foam-benefits)

### [Best Insulations For Attics: Performance vs. Budget August 23rd, 2023|6 min read](https://scsfoam.com/blog/best-attic-insulations)

Location

1574 Buchanan Trail East,

Greencastle, PA 17225

Phone: [(717) 895-3498](tel:7178953498)

Connect With Us

- [Facebook](https://www.facebook.com/p/South-Central-Services-Insulation-100057064885687/)
- [Instagram](https://www.instagram.com/scsfoam/)
- [YouTube](https://www.youtube.com/@scsfoam)
- [info@scsfoam.com](mailto:info@scsfoam.com)

Services

- [Attic Insulation](https://scsfoam.com/attic-insulation)
- [Basement Insulation](https://scsfoam.com/basement-insulation)
- [Crawl Space Repair](https://scsfoam.com/crawl-space-encapsulation)
- [Commercial Spray Foam](https://scsfoam.com/commercial-spray-foam/)
- [New Home Insulation](https://scsfoam.com/new-home-construction-insulation/)
- [Pole Building Insulation](https://scsfoam.com/pole-building-insulation)
- [Air-Sealing](https://scsfoam.com/air-sealing)
- [Blower Door Tests](https://scsfoam.com/blower-door-tests)

Pricing Information

- [Our Rates](https://scsfoam.com/our-rates)
- [Calculators](https://scsfoam.com/pricing-calculators)
- [Financing Options](https://scsfoam.com/financing-options/)
- [Rebate Information](https://scsfoam.com/rebates)
- [Pricing Articles](https://scsfoam.com/blog/tag/product-pricing)

Proud Member of Cumberland Valley Business Alliance

 

 

Company

- [Our Service Areas](https://scsfoam.com/our-services-areas)
- [Our Products](https://scsfoam.com/our-products)
- [Our Team](https://scsfoam.com/our-team)
- [Contact Us](https://scsfoam.com/contact/)
- [Join Our Team](https://scsfoam.com/our-team#hiring)
- [Privacy Policy](https://scsfoam.com/privacy-policy)

Learn More

- [FAQ](https://scsfoam.com/faq/)
- [Learning Center](https://scsfoam.com/learning-center)
- [Downloadable Resources](https://scsfoam.com/downloadable-resources)

 © 2026 South Central Services  
All Rights Reserved.

```json
{
  "@context" : "https://schema.org",
  "@type" : "BlogPosting",
  "author" : {
    "@type" : "Person",
    "name" : "Kilian Agha",
    "url" : "https://scsfoam.com/blog/author/kilian-agha"
  },
  "dateModified" : "2025-04-28T17:14:29.967Z",
  "datePublished" : "2024-12-18T17:00:00.000Z",
  "headline" : "Why You Should Remove Existing Insulation When Insulating Your Attic",
  "mainEntityOfPage" : {
    "@id" : "https://scsfoam.com/blog/why-remove-existing-insulation-when-insulating-your-attic",
    "@type" : "WebPage"
  },
  "publisher" : {
    "@type" : "Organization",
    "logo" : {
      "@type" : "ImageObject",
      "url" : "https://scsfoam.com/hubfs/branding/SCS-Updated-Logo_Horizontal-2048x397.png"
    },
    "name" : "South Central Services"
  }
}
```