Insulation For Houses: The Ultimate Green Guide

Insulation For Houses: The Ultimate Green Guide

Insulation is an essential component of construction and energy efficiency, serves as a shield against temperature fluctuations.

The key to making the right choice lies in a few fundamental considerations. Firstly, where insulation is needed most and where it can have the greatest impact.

Secondly, the recommended R-values for different areas you plan to insulate. Insulation is strategically placed in areas prone to air leakage, such as the gaps within walls and the attic.

By doing so, it efficiently slows down the transfer of heat. By sealing these air leaks and appropriately insulating areas like the attic, crawl spaces, and basement, homeowners can anticipate saving an average of 15 percent on their heating and cooling expenses.

A well-insulated home should maintain a consistent indoor temperature without overloading your furnace or air conditioner.

The main goal of house insulation is to reduce heat loss in winter and heat gain in summer, which leads to better energy efficiency and lower heating and cooling costs.

Materials like fiberglass, cellulose, foam, and reflective insulation are used in walls, floors, ceilings, and attics for this purpose.

Proper insulation ensures a more consistent and cozy indoor environment while also contributing to environmental sustainability by decreasing carbon emissions.

Best Thermal Insulation Materials

Insulation For Houses
Best Thermal Insulation Materials

Choosing the appropriate insulation materials depends on your home's construction.

For dropped ceilings, spray foam insulation might be suitable, while blown insulation could be more effective in other parts.

From mineral wool to radiant barriers, spray foam insulation, fiberglass insulation, foam board insulation, blown in cellulose insulation or some other less common form such as sheep’s wool, each one is measured in terms of its R-Value.

Green Attic Insulation experts can assess your home and recommend the best solution for your needs.

What Is R-Value

What Is R-Value
What Is R-Value

Insulation performance is measured through the R-Value, which means heat retention capability. R-Value indicates insulation's heat resistance, denoting how well it hampers heat flow.

R stands for Resistance to heat loss.

In Illinois, standards are shifting toward a 4.0 Air Exchange Rate and R-values aligned with optimum norms. For instance, in Chicago, R-Value is employed to measure standards, ranging from 0 to 70, illustrating resistance to heat loss.

Recommended R-Values:

Attics: R49-60
Sidewalls: R21
Cantilevered Floors: R38
Transition Walls: R21
Basement Walls: R13
Crawlspace Walls: R21

However, incorrect installation can lead to air gaps, diminishing efficiency,

Issues include:

  • Falling Below Standards
  • Moisture Concerns
  • Absence of Insulation
  • Damp Insulation
  • Compacted Insulation
  • Uninsulated Exhaust Ducts

Eco-Friendly Insulation

Eco-Friendly Insulation
Eco-Friendly Insulation

Eco-Friendly insulation means using materials and methods that help the environment and keep things sustainable. This includes using insulation stuff made from things that can be used again, like old clothes or natural fibers.

It's also important that these materials don't let out harmful gases. Some examples are: recycled denim, cellulose, wool, cork, and natural fibers.

Mineral Wool Insulation

Mineral Wool Insulation
Mineral Wool Insulation

Rockwool or mineral wool is a fiber-based insulation that resembles fiberglass but is stiffer and denser.

It comes in two main types: one made from natural stone fibers like volcanic rock, and the other from spinning steel production waste called slag. Both types contain up to 90% recycled content.

Mineral wool is available in batts and loose-fill forms, suitable for various home insulation needs. It offers thermal insulation benefits, noise reduction, and fire protection.

Moreover, its thermal performance, especially in traditional 2x4 walls, achieves an impressive R-value of 15, outperforming fiberglass insulation.

Spray Foam Insulation

Air Sealing
Spray Foam Insulation

Spraying foam into an open cavity initiates rapid expansion, with open cell foam swelling up to 100 times its original volume within seconds. Liquid foam insulation materials can be applied in different ways: they can be sprayed, poured, or injected.

This helps insulate and prevent air from escaping. Similarly, closed cell foam is suitable for commercial structures, featuring a lower expansion rate compared to open cell.

Transitioning to existing homes, prior to spray foam application, the removal of old insulation is imperative. This ensures a pristine surface for the spray foam to adhere to effectively.

Where to Insulate With Spray Foam? Roof /Ceiling Exterior Walls Headers/ Rim Joist Basement Concrete Walls Overhang Floors.

Spray foam will adhere to a variety of surfaces including wood, metal, glass, concrete house wrap and vapor barrier materials, etc. The optimal temperature for spray foam is 70-90 degrees.

Closed Cell Foam

Closed Cell Foam
Closed Cell Foam

Designed for residential use, closed ell foam serves as a versatile insulation system, replacing traditional materials like fiberglass or cellulose.

It finds application in various areas such as exterior walls, vented and unvented attics, attic door insulation, floors, foundations, crawl spaces, HVAC ducts, fluid tanks and cold storage units.

Closed-cell spray foam has a tighter seal and higher R-value per inch, offers the best results. making it highly suitable for residential, commercial, and industrial projects.

Additionally, closed cell spray foam is the top choice for better temperature control, strong resistance to moisture.

Open Cell Spray Foam

Open Cell Spray Foam
Open Cell Spray Foam

For achieving both indoor comfort and energy efficiency, open cell spray foam emerges as the logical choice.

Unlike closed-cell foam, light-density spray foam offers a lower R-value per inch, effectively sealing crevices and cracks to outperform traditional insulation materials like fiberglass and cellulose, making it suitable for various applications including attic and garage ceilings.

  • It comes at a lower cost than closed-cell foam.
  • It does not serve as a moisture barrier.
  • Its R-value per inch is lower.
  • It possesses a lighter and lower density.
  • It's easier to remove or demo when needed.

Cellulose Blown In Insulation

Cellulose Blown In Insulation

Cellulose insulation is made mainly from recycled paper, provides excellent thermal performance, reducing energy costs. It has a high R-value, meaning it's effective at keeping your home warm in the winter and cool in the summer.

Beyond thermal efficiency, cellulose is environmentally friendly, being both made from recycled material and biodegradable. Moreover, provides sound insulation and has high density that allows it to fill gaps more thoroughly than other insulation types.

Despite being paper-based, cellulose is safe as it's treated with fire retardants. Considering its characteristics, cellulose insulation is a superior choice for attic insulation.

Blow-in cellulose conforms to the American Society for Testing and Materials Standard Specifications (ASTM). Furthermore cellulose is treated with boric acid, which is an efficient pest hindrance.

When insects/pests absorb or come into contact with boric acid, it kills the creatures and they can not contaminate your insulation. Yet its pros and cons should be tailored to each home project:

  • Exceptional sound absorption and control.
  • Enhanced heat retention and protection from direct sunlight's radiation.
  • Fire-resistant, ensuring safety.
  • Resistant to pests, rodents, mold, mildew, and moisture.
  • Dense packing fills voids, unlike fiberglass batts.
  • Prevents sagging in stud cavities.
  • Liquid fire retardant infused for better insulation.
  • Blown-in cellulose is an efficient insulation method without removing drywall.

Fiberglass Insulation

Fiberglass Insulation
Fiberglass Insulation

Fiberglass insulation has been the conventional choice for home construction for decades. This material offered moderate insulation efficiency. It was conveniently sold in pre-sized rolls that fit standard building dimensions, making it a popular option.

In 1994, fiberglass insulation accounted for 90 percent of cavity insulation in new homes. Fiberglass insulation has been associated with health issues like skin, eye, and respiratory irritation, and possibly cancer.

Handling precautions involve wearing protective gear like dust masks, gloves, goggles, and covering the entire body with clothing and a hat.

Air Sealing

Air Sealing
Air Sealing

Air sealing works alongside insulation and is crucial for energy efficiency. The primary and most budget-friendly step to minimize drafts, sealing air leaks around home openings like AC window insulation.

Attic sealing prevents air leaks, it's wise to seal the house envelope during construction before installing drywall. Begin with sealing gaps outside the home using suitable materials; this investment pays off.

In addition, duct sealing Chicago experts recommend sealing ductwork with a moisture thermal pressure barrier at 2″ of closed-cell spray foam.

Attic Insulation

Attic Insulation
Attic Insulation

To solve problems caused by the stack effect, begin by sealing the attic floor to prevent air leaks. Without sealing the attic floor, rising heat meets cold air, leading to mold.

The solution involves sealing the attic floor, insulation baffles and a vapor barrier, ensuring proper ventilation, and adequate insulation. Air infiltration is almost as crucial as R-value for how warm or cool it stays.

When unconditioned outside air gets in, the heating and cooling systems have to work harder, using up more energy to balance things out. Ensuring that your attic sealing provides weather protection is essential for enhancing your home's energy efficiency.

When you seal up any gaps where air can escape and fix insulation problems in the attic, you stop your heated or cooled air from getting out. This makes your home more comfortable, saves energy, and lowers your utility bills.

For choosing the right attic insulation, it's essential to conduct some inspections:

  • Infrared Camera Inspection
  • Detect Air Leaks
  • Inspect for Mold
  • Address Ventilation Problems
  • Monitor Excessive Heat
  • Ensure Soffit Ventilation
  • Examine Rusty Roofing Nails
  • Manage Excessive Humidity
  • Ensure Even Insulation Distribution
  • Inspect Uninsulated Skylights
  • Examine Heating or Air Conditioning Ducts
  • Evaluate Exhaust Fans
  • Address Rodent or Nesting Issues

Wall Insulation

Wall Insulation
Wall Insulation

Green Attic Insulation provides a better alternative to fiberglass insulation for exterior walls. We use dense packed cellulose, which is blown into the stud cavity using netting to fill it completely.

Our Premium Class 1 insulation is safe, mineral-infused, and guards against fire, mold, and pests. Our high-powered machines fill each stud cavity with R3.5 per inch insulation.


  • Stops ice dams and water damage
  • Keeps your house warm in winter and cool in summer
  • Enhances indoor air quality
  • Prevents mold between stud cavities
  • Maintains consistent temperatures throughout the house

Using cellulose blown-In insulation between frames helps trap heat in rooms during winter which saves on ice dam removal cost and keeps heat out during summer, especially in exterior walls and cathedral ceilings.

It's also effective for reducing sound in basement ceilings. If your existing home’s walls are 2×4 framing instead of the newer thicker 2×6 then spray foam insulation is a difference maker over traditional insulation materials.

Knee Wall Insulation

Knee Wall Insulation
Knee Wall Insulation

Knee wall, also known by various names, close off attic spaces with limited height due to slanted roofs. They serve various purposes like storage, housing ductwork, furnace, and can be vented or unvented.

When considering knee wall insulation options, keep in mind the following:

  1. Fiberglass Batts: Common and cost-effective, but proper installation is crucial to avoid gaps.
  2. Rigid Foam Board: Offers a high R-value and creates a vapor barrier, though it's more expensive.
  3. Spray Foam Insulation: Provides the highest R-value and excellent sealing
  4. Blown-In Insulation: Suitable for challenging spaces but requires professional installation.

Irrespective of the insulation type, ensure you seal any air gaps in the knee wall before insulating.

For knee wall insulation, consider these approaches:

  1. Make the Knee Wall Area Like a Room
  2. Make it Like a Room for Ducts: If there's no good air flow, keep insulating from the attic to the floor.
  3. Insulate the Knee Wall Area: If you're not using it for storage, seal the framing and insulate the wall for better warmth.
  4. Ventilate the Knee Wall: Use vents to let air flow, but be careful about adding humidity that can hurt wood and other materials.

Basement Insulation

basement insulation
Basement Insulation

Enhance your home's energy efficiency and comfort through a basement insulation.

Employ quality materials such as:

  • Cellulose
  • Spray Foam
  • Fiberglass

Basement insulation options include fiberglass for below-grade areas, mineral wool for furnace room ceilings, cellulose for above-grade walls and ceilings, and closed-cell spray foam for rim joists.

Closed-cell spray foam is applied directly to foundation walls, providing a moisture, air, and thermal barrier. Insulating basement (below-grade) areas typically involves fiberglass or cellulose, provided there's a vapor barrier.

Prioritize water management around the property before finishing a basement to ensure effective waterproofing. Lastly, avoid insulating a damp basement.

Insulation Removal

Insulation Removal
Insulation Removal

You need to do insulation removal under the following circumstances:

  1. After Fire or Water Damage: Insulation should be removed if it has been exposed to fire or water damage.
  2. Presence of Untreatable Mold: If there's untreatable mold on your attic insulation, it needs to be removed.
  3. Substantial Animal Infestation: Insulation should be removed if you've experienced a significant animal infestation from mice, squirrels, chipmunks, or raccoons in your attic.

Moreover, the exposure to vermiculite insulation can lead to severe health effects.

Inhaling or ingesting asbestos insulation can cause inflammation and scarring in various organs, resulting in multiple health problems over time, including:

  • Lung Cancer
  • Mesothelioma:
  • Asbestosis
  • Other Cancers

It's important to note that the severity of these health risks depends on factors such as exposure duration, intensity, asbestos fiber type, and individual susceptibility.

As an alternative, blown-in insulation commonly includes fiberglass and cellulose options. Cellulose insulation is a healthier and eco-friendly alternative to blown-in fiberglass.

Furthermore, it resists mold growth and offers better thermal resistive properties (higher R-value) than blown-in fiberglass insulation.

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