R13 vs R19 Insulation: Which One Should You Choose?

Having proper thermal insulation in your home is crucial for energy efficiency and comfort. Two of the most common insulation types used in homes are R13 and R19 fibreglass batt insulation. But what is the difference between R13 and R19 insulation, and which is better for your home?

In this article, we will compare R13 vs R19 insulation for homes to help you determine which insulation rating is right for your specific climate zone and location. We will look at the insulating ability of R13 and R19 insulation, where each type is ideally installed in a home, and the costs of R13 vs R19 insulation per square foot.

With energy prices on the rise, investing in proper insulation for your attic spaces, exterior walls, crawl spaces and more can pay dividends through energy savings. Understanding the differences between R13 and R19 insulation can ensure you get the right thermal protection for your home.

Let’s dive in!

R-Value Explained: A Guide to Understanding Insulation Ratings

The R-value is a measure of an insulation’s ability to resist heat flow and provide thermal protection in your home. Understanding R-values can help you choose the right types and amounts of insulation for your climate.

What is R-value?

The R-value indicates the insulating ability of a material. The higher the R-value, the more effective the insulation is at slowing heat transfer and reducing energy loss. R-value is measured per inch of material thickness.

The R-value depends on the type of insulation, its density, and its thickness. The higher the R-value, the better the thermal insulation performance.

Typical R-Values for Home Insulation

  • Attic spaces: R-30 to R-60. Most attics should have at least R-30 insulation. In cold northern regions, R-49 to R-60 may be recommended.
  • Exterior walls: R-13 to R-23. R-13 is the minimum for 2Ă—4 framed exterior walls in most U.S. climate zones. R-15 to R-21 is typical for 2Ă—6 framing.
  • Crawl spaces: R-19 to R-30. Crawl spaces should have R-19 on walls and R-30 on ceilings/floors.
  • Floors over unheated areas: R-25 to R-30.

Factors Affecting Recommended R-Value

Several factors determine the ideal R-value for your home:

  • Climate zone: Colder regions need higher R-values to reduce heat loss. The U.S. Department of Energy provides climate zone maps.
  • Existing insulation levels: Adding insulation improves R-values. Check current levels before planning upgrades.
  • Insulation type: Different materials like fibreglass, cellulose, and foam have varying R-values at certain thicknesses. Compare options.
  • Energy costs: Higher R-values reduce energy consumption for heating and cooling, saving on utility bills. Consider long-term savings.
  • Building assembly: Insulate all elements—walls, ceilings, floors—for optimal efficiency. Don’t forget crawl spaces, attics, and exterior door frames.

Understanding R-values helps optimize insulation for maximum energy efficiency and thermal protection. Consult an insulation contractor to determine the ideal R-values for your climate and home. Proper installation is also key to realize the full benefits of insulation.

Key Differences Between R13 vs R19 Insulation

r19 insulation
image source: amerhart.com

The main difference between R13 and R19 insulation is the insulating ability, as measured by R-value.

R13 insulation has an R-value of around 13, while R19 insulation has an R-value of around 19. The R-value indicates an insulation’s resistance to conductive heat flow – the higher the R-value, the better it insulates.

This means R19 insulation provides about 46% more insulating power per inch compared to R13. R19 is better at slowing heat transfer and retaining indoor temperatures.

At standard thicknesses, R13 insulation is around 3.5 inches thick, while R19 is approximately 6 inches thick. The extra thickness contributes to the higher R-value of R19.

R19 insulation delivers greater thermal protection and energy efficiency compared to R13. R19 is typically recommended for colder climates, while R13 may suffice for milder regions.

R-Value Comparison

The main difference lies in the insulating ability as measured by the R-value:

  • R13 insulation has an R-value around R13, depending on the exact material and thickness. This means R13 provides an approximate R-value of 13 as its thermal resistance.
  • R19 insulation has a higher R-value around R19. Therefore, R19 offers about 46% greater insulating power per inch compared to R13 insulation.

The higher the R-value, the better the insulation resists conductive heat flow. R19 insulation provides more effective thermal protection than R13 for a given thickness.

Thickness and Coverage

  • Standard R13 insulation is usually around 3.5 inches thick. At this thickness, fiberglass batt insulation has an R-value of 13.
  • R19 fibreglass batts are approximately 6 inches thick. The added thickness increases the R-value to around 19.
  • To achieve equivalent thermal performance as R19, R13 insulation would need to be installed thicker – but it may not be practical or cost-effective to add that much extra thickness with an R13 product.
  • R19 insulation covers 14.4 square feet per batt at its standard width. R13 batts cover 21 square feet per piece.

Climate Differences

  • R13 insulation is often the minimum recommended for walls and ceilings in milder climates like the southern U.S.
  • For colder regions like the northern U.S. and Canada, building codes may require R19 insulation or higher. The added insulating power of R19 helps retain indoor heat better.
  • Upgrading from R13 to R19 insulation makes sense for homes in cold climates lacking adequate insulation. R19 helps reduce heat loss through the building envelope.

Cost Considerations

  • R19 insulation costs more upfront – about 15-20% more than R13 per square foot.
  • However, the boosted energy efficiency from R19 insulation leads to greater long-term savings on heating/cooling costs.
  • Carefully evaluate your climate zone, existing insulation levels, and energy costs to determine whether to invest in R13 vs R19 insulation. Consider the payback period for energy savings.

For many homes, choosing R19 over R13 provides better thermal performance for marginal upfront cost. R19 insulation offers more energy efficiency for colder regions and poorly insulated houses. Consult with insulation contractors to make sure you select adequate R-values for your climate zone.

Recommendations for R13 vs R19 Insulation by Climate Zone

Recommendations for R13 vs R19 Insulation by Climate Zone
image source: havelockwool.com

When choosing insulation for your home, comparing R13 vs R19 recommendations by climate zone can help select the right R-value. Here are general guidelines for tailoring R13 and R19 insulation to different U.S. regions.

Warm Climates

In warm southern states like Florida, Georgia, South Carolina, etc., R13 insulation is usually sufficient for:

  • Exterior walls
  • Crawl spaces
  • Ceilings/roofs

R19 insulation may be overkill for mild, warmer climates that rarely experience freezing temperatures. R13 provides adequate thermal protection in wall cavities and attic spaces.

Moderate Climates

For moderate climates like Tennessee, Kentucky, Virginia, etc., a hybrid approach combining R13 and R19 is recommended:

  • Use R13 insulation for exterior walls in these regions. R13 delivers satisfactory R-value for 2Ă—4 or 2Ă—6 framed walls.
  • R19 insulation for attic spaces helps keep homes cooler in summer and warmer in winter.
Insulation TypeWallsAttic

Colder Climates

In colder northern states like Minnesota, Maine, North Dakota, etc., R19 insulation is advisable for both walls and attics:

  • R19 walls better resist heat transfer compared to R13, helping retain indoor warmth.
  • Likewise, R19 attics provide necessary thermal performance in harsh winters.

Upgrading wall insulation from R13 to R19 makes the most impact on older homes in cold climates lacking adequate insulation.

Insulation TypeWallsAttic


  • New construction may warrant R21+ walls in cold climates for superior efficiency.
  • Budget constraints may dictate R13 walls for cost savings, even in cold zones. Properly installed R13 is better than nothing.
  • Likewise, some homeowners may need to stick with R13 attics based on limited funds.

Work with insulation contractors to tailor R-value recommendations to your climate zone, home efficiency goals, and budget. Proper installation also ensures insulation achieves the rated R-value.

Installation and Coverage Comparison of R13 vs R19 Insulation

Proper installation is key to achieving the full benefits of insulation. Here is an overview of installation methods and coverage areas for R13 and R19 insulation.

Installation Methods

R13 and R19 insulation are commonly available as fiberglass batts and rolls. Installation approaches include:

  • Friction-fitting batts between wall studs or joists
  • Securing with staples
  • Embedding rolls in blown-in insulation

No matter the R-value, ensure insulation makes full contact with surfaces and completely fills cavities without gaps or compression.

Hiring a professional is recommended to achieve proper insulation density and alignment. DIY installation can risk air pockets, sagging, and reduced R-value.

Coverage Areas

  • Standard R13 fiberglass batts are usually 21 inches wide and cover ~21 square feet per piece when installed between 16-inch on-centre wall studs.
  • R19 batts are 20 inches wide and cover ~14.4 square feet per piece, due to the increased thickness.

To calculate insulation needs:

  • Measure wall, ceiling, and floor square footage requiring insulation.
  • Divide total area by coverage area per batt based on insulation type.
  • Buy 10-15% extra to account for custom fitting.

Pros and Cons of R13 vs R19

R13 pros: covers more area per batt, lower cost

R13 cons: less insulation thickness and R-value

R19 pros: higher insulating value, better for colder climates

R19 cons: covers less area per piece, costs more

Evaluate your climate, existing insulation, and budget when deciding between R13 and R19. And make sure to get professional installation.

Cost Comparison of R13 vs R19 Insulation

When choosing insulation for your home, it’s important to understand and compare the costs of R13 vs R19. While R19 has a higher upfront cost, it delivers better long-term energy savings that can yield a faster payback compared to R13.

Cost Per Square Foot

On average, the material cost per square foot is:

  • R13 insulation: $0.30 to $0.45 per square foot
  • R19 insulation: $0.35 to $0.55 per square foot

So R19 insulation costs about 15-20% more than R13 insulation per square foot.

Total Installation Cost

For example, let’s consider a typical single-story house:

  • 1500 square feet attic
  • 1000 square feet of exterior wall space

For DIY installation using fiberglass batts:

  • R13 insulation would cost $750 – $1,050 total
  • R19 insulation would be $1,050 – $1,300 total

Having a contractor install the insulation is more labour-intensive and usually around 30% extra cost.

Return on Investment

The payback period – how long it takes energy savings to outweigh the upfront cost – is an important consideration.

In cold climates, R19 insulation can offer full payback in 2-5 years through lower heating bills compared to R13. In moderate climates, the payback period may extend to 5-8 years.

Other Cost Factors

  • Specials and rebates can reduce installation costs for either insulation.
  • DIY insulation can save on labour but has a higher margin of error.
  • Professional installation ensures proper insulation density and alignment.

Evaluate your climate zone and do a thorough ROI analysis when budgeting for R13 or R19 insulation. The added upfront investment for R19 pays dividends through energy savings over time.

FAQs: R13 Vs R19 Insulation

Is it easy to add more insulation over existing R13?

Yes, it’s relatively easy to add more insulation over top of existing R13 insulation. Ensure proper density and alignment to maximize effectiveness – hiring a professional is recommended.

Should I replace R13 with R19?

In colder climates, replacing R13 walls with R19 can provide better insulation, but evaluate costs. Adding R19 over R13 in the attic is a lower effort and delivers good results.

What’s the best insulation for basement walls?

R10 to R15 rigid foam boards work well for basement walls. Fiberglass and cellulose batts can also be effective if walls are properly sealed and have vapour barriers.

Can too much insulation cause problems?

Excess insulation can potentially cause moisture issues if airflow is restricted. Follow regional building code recommendations for your climate zone.

How much does it cost to upgrade attic insulation?

Upgrading to R38 attic insulation costs $1,000-$2,000 for a typical 1500 sqft attic, with higher costs for difficult access attics. Evaluate payback period.


Both R13 and R19 insulation offer benefits for thermal protection in homes. R13 insulation provides adequate insulating ability for many climate zones and areas like exterior walls and crawl spaces.

R19 insulation gives greater thermal protection and energy efficiency, making it ideal for attic spaces and northern regions with more extreme heat loss. The type of insulation should be selected based on the climate zone, as well as where it will be installed.

Factors like cost should also be weighed. With proper installation, both fiberglass batt insulation types can help reduce energy costs and keep homes comfortable.

Careful consideration of R-values and location needs will ensure your home has the right thermal insulation to meet its energy efficiency goals.

About Mohammad Sameer

My name is Mohammad Sameer, the founder of SoundproofGears. My hypersensitive hearing turned me into a lifelong seeker of silence. After years of research, I've become an expert on soundproofing techniques and materials. In November 2022 I launched this site to share my knowledge and help others find acoustic sanctuary. About More

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