Adding Insulation to an Existing Attic: Add More or Replace It?

Adding insulation to an existing attic can improve comfort and reduce heat transfer through the ceiling, but an attic insulation upgrade does not always require removing everything already there.

In many homes, dry and uncontaminated insulation can remain in place while new material is added on top. Removal becomes more appropriate when the existing insulation is wet, moldy, contaminated by pests, affected by smoke or fire, or preventing important repairs.

This guide explains when adding attic insulation over existing material makes sense, when homeowners should replace attic insulation, how air sealing fits into the project, what R-value to consider, and what upgrading or replacing attic insulation may cost.

For a broader look at insulation projects throughout the home, explore Home Insulation Solutions.

Can You Add Insulation Over Existing Insulation?

Yes. In many conventional vented attics, homeowners can add new insulation over existing insulation without removing the original material.

ENERGY STAR notes that old attic insulation generally can remain unless it is wet, moldy, smelly, or contaminated with animal waste. Loose-fill insulation can be installed over existing batts, and unfaced batts can sometimes be installed over loose-fill insulation. nsulation is most practical when the existing material is:

• Dry
• Free of mold and visible contamination
• Not affected by roof or plumbing leaks
• Free of animal nesting and waste
• Distributed reasonably evenly
• Not blocking soffit vents or other required ventilation openings
• Safe to work around
• Located at the correct thermal boundary

Age alone is not a reason to remove insulation. Fiberglass, cellulose, and mineral wool do not automatically become unusable after a set number of years. Their condition, thickness, coverage, and exposure to moisture or contamination matter more than the installation date.

Attic Insulation Upgrade Decision Guide

Existing Attic Condition	Add More Insulation?	Remove or Replace?	What to Address First
Dry insulation in good condition but below the desired R-value	Usually	Usually not	Air sealing and ventilation
Insulation is uneven or has isolated low areas	Often	Only damaged sections	Redistribute material and inspect for air movement
Clean insulation has settled over time	Often	Usually not	Confirm remaining depth and R-value
Insulation is wet from a recent roof leak	Not yet	Possibly	Repair the leak and assess whether the material can dry
Persistent mold growth or rotted framing is present	No	Often	Moisture correction and remediation
Rodent, bird, bat, or raccoon waste is present	No	Often	Pest removal, exclusion, and cleanup
Strong urine, smoke, or chemical odors remain	No	Often	Identify and remove the contamination source
Vermiculite insulation may be present	Do not disturb	Specialist assessment	Follow asbestos precautions
Spray foam is installed along the roof deck	Assembly-specific	Assembly-specific	Evaluate the roofline and attic design

An attic may need more insulation when the existing layer is too thin, uneven, compressed, or missing around important areas. Comfort complaints can also point toward an attic problem, although insulation is not the only possible cause.

Measure the Existing Insulation

Check the insulation depth in several locations rather than measuring only near the attic hatch. Insulation may be deep in the center of the attic but thin near eaves, exterior walls, walkways, or areas disturbed by previous work.

The depth must be considered alongside the insulation type. Ten inches of one material may not provide the same R-value as ten inches of another.

When the insulation type is known, its estimated existing R-value can be calculated using the manufacturer’s information or a reasonable per-inch estimate. The final project should be based on the new product’s labeled installed R-value.

Look Across the Attic Floor

You may need additional insulation when:

• The tops of the ceiling joists remain visible
• Insulation sits below the joist depth
• Low spots or bare areas can be seen
• Material has been moved away from wiring, ducts, or access areas
• Batts have gaps between their edges and the framing
• Batts are compressed, folded, or poorly fitted
• Loose-fill material has been displaced by air movement
• Storage boards have compressed the insulation below them

Insulation should form a continuous, even thermal layer. A deep pile in one area does not compensate for gaps somewhere else.

Consider Comfort and Performance Signs

Possible symptoms of an under-insulated or poorly sealed attic include:

• Rooms directly below the attic that are difficult to heat or cool
• Noticeably hot or cold ceilings
• Uneven upstairs temperatures
• Drafts around ceiling penetrations or the attic hatch
• Higher heating or cooling use without another clear cause
• Ice dams in cold climates
• Dust or darkened insulation around air leaks

These signs do not prove that insulation is the only problem. Leaky ducts, HVAC sizing, solar exposure, window performance, ventilation, and air leakage can produce similar symptoms.

A home energy assessment can help separate insulation problems from other causes.

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Signs Existing Attic Insulation Should Be Removed

Complete attic insulation removal is not the default starting point. It is usually reserved for conditions that make the existing material unsafe, unsanitary, difficult to reuse, or incompatible with the planned work.

Wet or Water-Damaged Insulation

Insulation that has absorbed water may lose thermal performance, compress, develop odors, or contribute to moisture problems in nearby framing and ceiling materials.

A small, recently dampened area may sometimes be dried or replaced locally. Widespread saturation, repeated leaks, or insulation that remains wet generally requires more extensive removal.

The roof leak, plumbing leak, condensation problem, or improperly vented exhaust fan must be corrected before new insulation is installed.

Mold and Rotted Framing

Visible mold or decay on roof sheathing, rafters, trusses, or ceiling joists indicates a moisture problem that should be investigated before the attic is covered with more material.

Porous materials affected by mold can be difficult to clean fully. EPA guidance emphasizes correcting the source of moisture as part of any mold cleanup. Waste and Nesting

Insulation may need to be removed when it contains:

• Rodent urine or droppings
• Bird or bat waste
• Animal nesting material
• Dead animals
• Flea, tick, or insect contamination
• Persistent odors associated with animal activity

The animal entry points should be located and sealed before replacement insulation is installed. Otherwise, pests may return and contaminate the new material.

Smoke, Fire, or Chemical Contamination

Smoke particles, soot, fire-suppression chemicals, oil, or other contaminants can settle deeply into fibrous insulation. Removal may be necessary when odors or residue cannot be addressed through localized cleaning.

Fire-damaged wiring, framing, recessed lights, chimneys, and flues should also be inspected before the attic is reinsulated.

Suspected Vermiculite Insulation

Vermiculite attic insulation may contain asbestos. It often appears as lightweight, pebble-like or flaky granules and may be gray, brown, silver, or gold.

EPA recommends assuming vermiculite attic insulation may contain asbestos and leaving it undisturbed. Homeowners should not vacuum, shovel, rake, sample, or remove it themselves. Work that may disturb the material should be evaluated by a properly trained asbestos professional. nsive Access Is Needed

Extensive Access Is Needed

Removing some or all of the existing insulation may also be appropriate when contractors need clear access to:

• Perform comprehensive attic-floor air sealing
• Repair damaged ceilings
• Replace unsafe wiring
• Correct improperly installed recessed lighting
• Repair extensive ductwork
• Inspect concealed framing
• Address widespread pest or moisture damage

Complete removal is not always necessary. In many cases, insulation can be moved aside or removed only from the affected areas before being returned or replaced.

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When Topping Off Attic Insulation Is Appropriate

Topping off insulation means adding enough new material to increase the attic’s overall R-value without removing most of the existing insulation.

It is often the most practical approach when the original material still provides useful thermal resistance but no longer reaches current recommendations or does not cover the attic evenly.

A top-up is generally appropriate when:

• The existing insulation is clean and dry
• No active roof, plumbing, or condensation problems are present
• Pest activity has been ruled out
• The attic floor is the intended thermal and air boundary
• Existing insulation remains usable
• Air leaks can be sealed before installation
• Soffit vents and other ventilation paths can be protected
• Required clearances around flues, chimneys, lights, and heat-producing equipment can be maintained
• The new insulation can be installed without compressing the old layer
• The combined insulation level will meet the project’s target

Loose-fill fiberglass or cellulose is frequently used for attic top-ups because it can cover framing and irregular areas more evenly than batts.

Mineral wool batts may also be useful in accessible, regularly framed areas. Homeowners considering this material can review mineral wool attic insulation for more detail about fit, R-value, cost, and attic applications.

When Attic Insulation Must Be Replaced

Replacement becomes the more practical option when the existing insulation cannot be left safely in place or would prevent the attic from being repaired correctly.

Full or substantial replacement may be needed when:

• Large areas are wet or water-damaged
• Mold growth is widespread
• Insulation contains animal urine, droppings, or nesting debris
• Smoke or fire contamination has caused persistent residue or odors
• Hazardous material must be professionally abated
• Insulation has been mixed with construction debris or other contaminants
• Extensive electrical, structural, duct, or ceiling repairs require open access
• The existing installation is so incomplete or damaged that retaining it provides little benefit
• The home is changing from one attic design to another

Replacement should be treated as a sequence rather than a single step:

1. Identify why the existing insulation failed.
2. Correct water, pest, electrical, ventilation, or structural problems.
3. Remove affected material using appropriate containment and safety practices.
4. Clean and inspect the exposed attic.
5. Air seal the intended boundary.
6. Correct ventilation and clearance issues.
7. Install new insulation at the specified depth and R-value.
8. Document the completed work.

Simply replacing insulation without correcting the cause of the damage can lead to the same problem returning.

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Can Fiberglass, Cellulose, and Mineral Wool Be Mixed?

Fiberglass, cellulose, and mineral wool can often be layered in an attic floor assembly. The insulation materials do not have to match simply because one type was installed first.

ENERGY STAR specifically notes that loose-fill insulation can be added over fiberglass batts or blankets and that unfaced fiberglass can be installed over loose-fill material. important questions are whether the existing insulation is dry, whether the new layer can be installed evenly, and whether the combined assembly avoids unnecessary vapor-retarder layers.

Fiberglass Over Existing Insulation

Fiberglass insulation is available as batts, rolls, and loose-fill material.

Unfaced fiberglass batts may be installed over existing batts in some open attics. Where possible, the upper layer is commonly placed perpendicular to the joists to reduce heat flow through the framing and cover joints in the lower layer.

Installing batts over uneven loose-fill material can be more difficult. The batts may bridge over low areas, leave concealed gaps, or compress the material underneath.

Cellulose Over Existing Insulation

Cellulose insulation is commonly blown over existing attic-floor insulation. Its loose-fill form can cover framing, small gaps, and irregular areas effectively.

The installer must account for the product’s installed density, settled thickness, required bag count, and ventilation clearances. Depth alone should not be used without checking the product coverage chart.

Mineral Wool Over Existing Insulation

Mineral wool batts can be installed in accessible attic areas where they can be fitted closely without excessive cutting or compression.

Because mineral wool is commonly sold in batt form, it may be less convenient than blown insulation for large attic floors with many obstructions. It can make sense for targeted areas, regular framing cavities, knee walls, or locations where its density, fire resistance, or sound performance is useful.

Avoid Adding a Second Facing

Paper or foil-faced insulation should generally not be used as the upper layer of an attic top-up unless the assembly has been specifically designed for it.

An unnecessary facing within the insulation layers can restrict drying and create an unintended vapor-control layer. ENERGY STAR recommends unfaced batts when fiberglass is added over existing loose-fill insulation. Facts

• Insulation types do not always need to match.
• The upper layer should normally be unfaced.
• Existing loose-fill insulation should not be compressed.
• The combined R-value should be estimated using the remaining existing insulation and the labeled value of the new product.
• Mixing materials does not correct air leaks, moisture problems, or poor ventilation.

Should You Air Seal Before Adding Insulation?

Air sealing should generally be completed before additional attic insulation is installed.

Insulation slows heat transfer through materials. Air sealing addresses uncontrolled airflow through gaps, cracks, and openings. A home can have a thick layer of insulation and still lose conditioned air if those openings remain unsealed.

Common attic-floor air leaks include:

• Plumbing and wiring penetrations
• Open wall cavities
• Dropped soffits
• Gaps around duct chases
• Attic hatches and pull-down stairs
• Recessed lighting penetrations
• Partition-wall top plates
• Bathroom and kitchen exhaust penetrations
• Gaps around chimneys and metal flues

Air sealing becomes more difficult after these areas are buried beneath new loose-fill insulation. Moving the existing insulation aside locally before sealing is often enough; full insulation removal is not automatically required.

ENERGY STAR recommends sealing attic-floor air leaks before adding insulation because the openings are easier to locate and reach before the new insulation layer covers them. ty Around Heat-Producing Components

Ordinary canned spray foam should not be applied directly against hot flues or chimneys. These areas may require metal flashing, code-required clearances, and high-temperature sealant.

Older recessed lights may also require protective covers or clearance from insulation unless they are rated for direct insulation contact.

Homes with fuel-burning appliances may need combustion-safety testing after major air sealing. Reducing uncontrolled air leakage can affect how naturally vented appliances draft.

Do Not Block Attic Ventilation

In a conventional vented attic, soffit vents should remain open. Baffles or rafter vents may be needed to keep insulation away from the roof deck and preserve airflow from the eaves.

An unvented attic insulated at the roofline operates differently. Homeowners should not automatically add attic-floor insulation beneath an existing spray-foamed roof deck without confirming where the home’s thermal and air boundaries are intended to be.

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How Much Insulation and R-Value Does an Attic Need?

R-value measures resistance to heat flow. A higher R-value provides greater resistance under the conditions used to rate the insulation.

The appropriate attic R-value depends on:

• Climate zone
• Local building and energy codes
• Existing insulation
• Attic design
• Available space
• Insulation material
• Installation quality
• Whether ducts or HVAC equipment are in the attic
• Whether the attic is vented or unvented

Many attic retrofit recommendations fall between approximately R-38 and R-60, but warmer climate zones and homes with existing insulation may require a smaller addition.

ENERGY STAR Retrofit Guidance

Recommended Insulation Additions for Existing Attics

Climate Zone	Add to an Uninsulated Attic	Add When Approximately 3–4 Inches Already Exists
Zone 1	R-30	R-25
Zone 2	R-49	R-38
Zone 3	R-49	R-38
Zones 4A and 4B	R-60	R-49
Zones 4C, 5, and 6	R-60	R-49
Zones 7 and 8	R-60	R-49

The installer’s proposal should identify:

• Existing insulation type and estimated R-value
• New insulation product
• Number of bags, batts, or packages
• Installed thickness
• Settled thickness when applicable
• Added R-value
• Estimated final combined R-value
• Area being insulated
• Ventilation and air-sealing work included

The best top-up method partly depends on what is already in the attic.

Adding Insulation Over Existing Batts

Existing batts should first be checked for gaps, compression, folding, and poor contact with the ceiling surface.

Where the original batts are in good condition, common options include:

• Adding loose-fill fiberglass over the batts
• Adding loose-fill cellulose over the batts
• Installing a second layer of unfaced batts perpendicular to the framing
• Correcting isolated gaps before covering the lower layer

Loose-fill material is often useful because it covers the tops of joists and fills around irregular framing. A second batt layer can also work, but it must fit closely and remain uncompressed.

Adding Insulation Over Existing Loose-Fill

Loose-fill over loose-fill is often the simplest approach. The existing material can be leveled where needed and topped up using a compatible product.

Batts can sometimes be placed over loose-fill insulation, but the uneven lower surface makes careful installation more difficult. Problems may include:

• Compressing the existing material
• Leaving air pockets under the batts
• Bridging over low areas
• Creating gaps around framing and obstructions
• Making future attic access more difficult

When batts are used, they should be unfaced and supported without flattening the loose-fill layer.

Adding Insulation Around Attic Walkways

Boards, platforms, and stored belongings can compress attic insulation and interrupt the thermal layer.

A raised storage platform may be needed if the attic must remain accessible. Placing boards directly on top of insulation reduces its thickness and can make it difficult to reach the intended R-value.

The attic hatch, pull-down stair, and any permanent walkway should also be insulated and air sealed without preventing safe access.

Attics With Spray Foam at the Roofline

Spray foam installed against the roof deck is not simply another attic-floor top-up material. It may be part of an unvented or conditioned attic assembly.

Adding floor insulation beneath that roofline can change heat flow between the house and attic, isolate HVAC equipment from the conditioned space, or create unclear air and thermal boundaries.

Review the differences between open-cell spray foam and closed-cell spray foam before changing an existing roofline assembly.

Batts vs Loose-Fill for an Attic Top-Up

Comparing Attic Top-Up Methods

Top-Up Method	Where It Often Works Well	Main Advantage	Important Limitation
Blown-in fiberglass	Large open attic floors and irregular areas	Even coverage and familiar material	Requires correct depth and coverage
Blown-in cellulose	Retrofit attic floors and areas with many obstructions	Fills around framing and penetrations	Settled thickness and moisture conditions matter
Fiberglass batts	Open, regularly framed, accessible areas	Widely available and potentially DIY-friendly	Gaps and compression reduce performance
Mineral wool batts	Regular framing or targeted attic areas	Dense, firm fit with strong fire and sound properties	Often less convenient for large irregular attic floors
Spray foam at roofline	Carefully designed unvented attic assemblies	Combines air sealing and insulation	Higher cost and assembly-specific moisture and code requirements

Moisture, Mold, Pests, and Contamination

Insulation should not be used to cover an unresolved attic problem.

A thick new insulation layer can make leaks, mold, pest waste, and damaged wiring more difficult to find later. Inspection and correction should happen before the attic is topped up.

Moisture Sources to Check

Common attic moisture sources include:

• Roof leaks
• Plumbing leaks
• Ice-dam leakage
• Bathroom fans exhausting into the attic
• Kitchen exhaust ducts ending in the attic
• Clothes-dryer vents routed into the attic
• Leaking or poorly insulated HVAC ducts
• Gaps carrying warm, humid indoor air into a cold attic
• Blocked soffit vents
• High indoor humidity
• Improperly designed roofline insulation

The cause should be corrected before damaged insulation is replaced.

Mold Does Not Disappear Under New Insulation

Covering mold with new insulation does not remediate the affected material or fix the moisture source. EPA guidance identifies moisture control as the central part of preventing recurring mold growth. eas and large remediation projects require different responses. Homeowners should consider professional help when mold is widespread, hidden, associated with sewage or contaminated water, or linked to significant health concerns.

Pest Cleanup Should Include Exclusion

Removing contaminated insulation without closing animal entry points provides only a temporary fix.

A complete pest-related attic project may include:

1. Identifying the animal or insect
2. Removing active animals safely and legally
3. Closing entry points
4. Removing nesting material and contaminated insulation
5. Cleaning or treating affected surfaces when appropriate
6. Repairing damaged ducts, wiring, or vents
7. Reinstalling insulation

Do Not Disturb Suspected Hazardous Material

Vermiculite and other suspected asbestos-containing materials require special precautions. Ordinary shop vacuums, insulation blowers, rakes, and brooms can release and spread fibers.

Professional assessment should happen before any air sealing, insulation removal, blower-door testing, or attic work that could disturb the material.

Attic Insulation Upgrade and Replacement Costs

The cost of an attic insulation upgrade depends on whether the project involves a simple top-up or complete removal, cleaning, air sealing, repairs, and replacement.

National consumer cost guides place attic insulation installation broadly around $1 to $7 per square foot. Removing existing material is often an additional cost, and remove-and-replace projects may range from approximately $2 to $8.50 per square foot before unusual remediation expenses. cal Attic Insulation Planning Ranges

Attic Insulation Upgrade Cost Ranges

Project Scope	Approximate Planning Range	Important Cost Factors
General attic insulation installation	$1–$7 per sq. ft.	Material, R-value, access, region, attic size
Professionally installed blown-in insulation	$1–$4 per sq. ft.	Material, required depth, equipment, access
Professionally installed fiberglass batts	$2–$4 per sq. ft.	Framing layout, cutting, obstructions, labor
Spray foam insulation	$2–$5 per sq. ft.	Foam type, thickness, preparation, code-required coverings
Existing insulation removal	About $1–$1.50 per sq. ft. additional	Material, dust control, disposal, access
Remove and replace attic insulation	About $2–$8.50 per sq. ft.	Removal, new material, air sealing, cleanup
Moisture, mold, pest, or asbestos work	Additional and highly variable	Extent of contamination and specialist requirements

A top-up avoids much of the labor associated with:

• Vacuuming or bagging old insulation
• Carrying material out of the home
• Disposal fees
• Cleaning exposed ceiling surfaces
• Containment and dust control
• Replacing the full insulation depth

However, the lowest-cost quote is not necessarily the best scope. A proposal that skips air sealing, ventilation corrections, or moisture repairs may leave the attic’s main problems unresolved.

Factors That Increase Replacement Cost

Replacement costs may rise when:

• The attic has difficult or limited access
• Roof framing creates tight working areas
• The insulation is heavily contaminated
• Asbestos procedures are required
• Mold or rot affects framing
• Pest exclusion and sanitation are needed
• Duct repairs are included
• Electrical hazards must be corrected
• The attic hatch or walkways need rebuilding
• High R-values require substantial material depth
• Spray foam or another specialized system is selected

Homeowners comparing quotes should ask each contractor to separate removal, disposal, air sealing, ventilation work, new insulation, and remediation costs.

DIY vs Professional Attic Insulation Installation

Some straightforward attic insulation top-ups can be completed by experienced homeowners. Projects involving removal, contamination, spray foam, difficult access, or major air-sealing work are generally better suited to qualified professionals.

The decision should be based on the condition of the attic and the complexity of the work—not only on the insulation material being installed.

When DIY Installation May Be Reasonable

A DIY attic insulation upgrade may be practical when:

• The attic is dry, clean, and easy to access
• The existing insulation is free of mold, pests, and contamination
• No vermiculite or other suspected asbestos-containing material is present
• The attic floor is clearly the intended insulation boundary
• Air leaks are visible and safely accessible
• Soffit vents and other ventilation openings can be protected
• Electrical wiring and recessed lights do not create safety concerns
• Required clearances around chimneys, flues, and heat-producing equipment are understood
• The project involves a straightforward layer of batts or loose-fill insulation
• The homeowner can verify the required coverage, depth, and final R-value

Installing insulation correctly requires more than spreading material across the attic. Gaps, compression, blocked vents, insufficient depth, and poorly sealed penetrations can reduce the effectiveness of the upgrade.

When Professional Installation Is More Appropriate

Professional help is generally recommended when:

• Existing insulation needs to be removed
• The insulation is wet, moldy, or contaminated
• Rodent, bird, bat, or other animal waste is present
• Vermiculite or asbestos may be present
• The attic contains damaged or outdated wiring
• Fuel-burning equipment is located in the attic
• Extensive attic-floor air sealing is required
• Bathroom, kitchen, or dryer exhaust terminates in the attic
• Ductwork needs to be repaired, sealed, or reinsulated
• Access is tight, unstable, or hazardous
• Spray foam insulation is being considered
• The project changes the attic from a vented to an unvented assembly
• Roof leaks, damaged framing, or structural problems are present

Professionals may also be better equipped to maintain an even insulation depth, confirm product coverage, install ventilation baffles, and work safely around electrical and combustion-related hazards.

DIY vs Professional Comparison

Choosing Who Should Complete the Attic Upgrade

Project Condition	DIY Potential	Professional Advantage
Clean, open attic needing unfaced batts	Reasonable for experienced homeowners	Faster installation and more consistent fitting
Clean attic needing blown-in insulation	Possible with rental equipment and a helper	Better depth control and product coverage
Minor, accessible air sealing	Sometimes appropriate	Greater ability to identify hidden air leaks
Existing insulation removal	Limited	Specialized equipment, containment, and disposal
Pest-contaminated insulation	Not recommended	Safer cleanup and sanitation procedures
Suspected vermiculite or asbestos	Do not disturb	Proper assessment and regulated handling
Spray foam roofline installation	Not suitable for ordinary DIY work	Product training, ventilation planning, and code compliance
Complex vented or unvented attic	Limited	Building-science and moisture-management evaluation

Questions to Ask an Attic Insulation Contractor

Before hiring a contractor, ask:

• Will you inspect for roof leaks, moisture, pests, and damaged insulation?
• Is air sealing included before the new insulation is installed?
• How will soffit vents and attic ventilation be protected?
• What existing R-value do you estimate?
• What R-value will the completed attic provide?
• What insulation product and installed depth will be used?
• How many bags, batts, or packages are included?
• Are removal, disposal, and cleanup included in the quote?
• How will recessed lights, chimneys, flues, and wiring be handled?
• Will the completed insulation depth and coverage be documented?

Quotes should be compared by the work included, not only by total price. A lower quote may exclude air sealing, ventilation corrections, removal, or other work needed for the insulation to perform properly.

Related Insulation Resources

Mineral Wool Attic Insulation

Learn where mineral wool attic insulation can be used, how batts fit into attic assemblies, and what homeowners should consider about R-value, cost, and installation.

Fiberglass Insulation

Explore fiberglass insulation, including batts, rolls, and loose-fill products commonly used for attic top-ups.

Cellulose Insulation

Review cellulose insulation for information about loose-fill attic coverage, settling, moisture considerations, and installation.

Open-Cell Spray Foam

Learn how open-cell spray foam insulation behaves in wall and roofline assemblies and how it differs from conventional attic-floor insulation.

Closed-Cell Spray Foam

Explore closed-cell spray foam insulation for tight spaces, rooflines, vapor-control considerations, and higher R-value per inch.

R-Value

Use R-Value Explained to understand insulation ratings, climate considerations, installed thickness, and whole-assembly performance.

Frequently Asked Questions