With the rising cost of heating and cooling homes, insulation and insulators have become increasingly important for providing comfort, efficiency, noise control, thermal performance, thermal protection, and long-term affordability.
Recent reports show homeowners’ energy efficiency and thermal protection becoming more critical, with home heating expenditures rising significantly, making proper insulation more important than ever. But with so many insulation types and thermal performance numerical ratings, it can get confusing to determine what’s best for your climate and home.
This in-depth comparison guide from the insulation professionals at Phoenix Insulation Pros will break down the differences between the two most common wall insulations—R13 and R19.
You’ll learn the exact definition of R-value, what sets these two insulation ratings apart, when to use each one, and how upgrading insulation can benefit your home.
What Does R-Value Mean?
Before examining R13 and R19 specifically, it’s important to understand the concept of R-value and thermal insulation. R-value is a measure of an insulation material’s ability to resist heat transfer.
More specifically, it provides quantified thermal resistance to conduction, or heat flow through direct contact. The higher the R-value, the better the thermal insulation resists conductive heat transfer.
R-value takes into account the type of insulation, its intended use, density, and thickness. So improving any of these factors can increase effectiveness for higher R-value. Commonly used insulation materials include fiberglass batts, rigid foam boards, loose-fill or blown-in insulation, and closed-cell spray foam insulation.
Now that you understand the basics of R-value insulation ratings, let’s compare two of the most common wall insulation types—R13 and R19 fiberglass batts.
Key Differences Between R13 and R19 Insulation
R13 and R19 insulation provide graduated levels of thermal resistance and insulating performance.
As you can see, R19 insulation provides nearly 50% higher thermal resistance over R13 with an R-value of 19 over 13. However, several other factors distinguish these two common wall insulations.
What is R13 Insulation?
R13 batt insulation features an estimated R-value of 13 when installed properly. This meets the recommended minimum insulation value for above-grade frame walls in IECC climate zones 1 through 4 encompassing southern regions of the continental United States.
Constructed from compressed fibers typically made out of fiberglass, mineral wool, or natural fibers, R13 insulation is available in open batts without vapour retarders or fully enclosed for moisture control. Enclosed batts utilizing kraft or foil water barriers and value insulation work best for exterior wall installation.
Typical R13 batt characteristics include:
- Available material: fiberglass, mineral wool, natural fibers
- Enclosure: open or enclosed batts
- Faced options: unfaced, kraft paper or foil vapour retarders
- Thickness: 3/8” to 5/8” inches
- Width/length: fits standard stud spacing
With an average thickness ranging between 3/8 to 5/8 inches, R13 insulation fits well within standard wall stud cavities framed with 2×4 lumber.
This thickness is sufficient to fill the 3 1⁄2 inches of usable cavity space inside a 2×4 wall framed at 16 inches on the centre without excess compression or gaps after enclosed batt facers.
In addition to thermal insulative properties, R13 also dampens sound transmission through interior walls. This added sound control makes it a common choice for use in interior bedroom walls, media rooms, and noise barriers between living spaces.
What is R19 Insulation?
R19 insulation packs a punch with a beefy R-value of 19, over 30% higher than standard R13 batts. This elevated thermal resistance rating makes R19 insulation better equipped to block and slow heat transfer through exterior walls, ceilings and floors.
To achieve its higher R-value, R19 insulation is considerably thicker than R13 products. A common R19 fiberglass batt size is 6 1⁄4 inches thick by 15 1⁄4 inches wide to deliver an insulation value of around R18-21 when properly installed.
Typical R19 batt features include:
- Available material: fiberglass, mineral wool, natural fibers
- Enclosure: open or enclosed batt options
- Facer: kraft paper, foil, no facing
- Thickness: ~ 6 1/4″ inches up to 8+”
- Width/length: fits 24-inch on-centre stud spacing
The increased thickness of R19 batts makes them well suited to installing 2×6 framed walls with 5 1⁄2 inches of usable depth.
They can also work for 2×4 walls given deeper stud cavities or without drywall on one side. However, the tight fit can lead to compression and reduced effectiveness if not done properly.
The 2021 IECC building code sets standards for minimum R19 insulation in above-grade mass walls for climate zones 4 through 8 encompassing much of the northern continental regions with colder winters. Consequently, R19 batts see prolific use in insulating exterior house walls and ceilings underneath attics throughout these colder northern states.
R13 vs R19 Key Comparison Considerations
While both qualify as insulation despite the differing performance, some key factors determine whether R13 or R19 is better suited to your home’s insulation needs.
Climate Differences Dictate Insulation Needs
- Heating-dominated climates benefit more from high-performance insulation
- Cooling-dominated climates focus more on airflow and ventilation
Heating vs cooling needs:
- Northern states focus insulation efforts on retaining interior heat in winter = higher R-value
- Southern states care more about ventilation and moisture control = meeting code minimum
| Climate | Recommended Insulation |
|---|---|
| Colder Northern Regions | Higher R-value – R15 to R21+ |
| Warmer Southern Regions | Meets code – R13 |
The DOE Building America Program sets regional recommendations for insulation levels based on climate:
As a good rule of thumb:
- R13 = meets minimum code for southern zone passive homes
- R15-R21+ = optimal for colder regions focused on heating efficiency
Construction Factors
- Stud size dictates cavity depth
- New build vs retrofit impacts installation
Framing differences:
- 2×4 walls fit R13 smoothly, R19 requires careful install
- 2×6 walls easily accommodate thicker R19 batts
Considering your home’s unique construction is key for optimal insulation sizing. Identify framing materials and dimensions early on when specifying insulation needs.
Installation Configuration
- Layering 2 split R13 batts boosts performance
- Hybrid methods optimize coverage
Getting creative with installation methods enhances effectiveness. For example:
- Stack split R13 batts front and back with a gap for drainage
- Combine fiberglass for coverage with spray foam edges for air-sealing
Budget Concerns
- R19 costs 20-50% higher upfront over R13
- Air sealing and extra insulation works better than just R-value alone
- Higher efficiency cuts energy bills long-term providing a return on investment
Upgrading insulation does add cost, but not as much as you may think over the long run. Let’s compare high-level costs:
| Insulation | Cost per Square Foot | Total Cost 100 sq ft |
|---|---|---|
| R13 | $0.70 | $70 |
| R19 | $1.05 | $105 |
The insulation professionals at Phoenix Insulation Pros work with clients to balance budgets while reaching efficiency goals.
More expensive products combined with proper installation often provide much higher performance per dollar over cheap standalone solutions that neglect air sealing.
Is R19 Better Than R13 Insulation?
This common question leads many to assume R19 must insulate better based solely on the higher R-value. However, the answer depends greatly on your objective and the metrics used for scoring performance.
By the numbers, R19 supplies superior thermal resistance compared to R13 insulation of the same type and thickness. The 30-50% boost in R-value directly correlates to exponentially better resistance to conductive heat transfer. Closed-cell insulation outperforms in cold weather regions, focused on retaining heat inside the home.
However, R-value alone does not quantify all facets of performance. For example, R13 batt insulation provides respectable thermal resistance meeting base-level code requirements while also absorbing sound for increased noise control.
Benefits provided by R13 insulation:
- Meets IECC code for thermal insulation in southern climate zones
- Fits without compression into standard 2×4 framed walls
- Offers sound dampening for interior noise control
- Typically more affordable upfront cost over higher-grade insulation
So while R19 represents a big jump in conductive insulation capability, R13 serves an important purpose in meeting multiple needs in one product.
For warmer southern zones focused on room-to-room sound transmission and basic insulation with a lower budget, R13 batts check all the boxes. It comes down to understanding your needs.
When to Upgrade Wall Insulation to R19
New Home Construction
Installing R19 insulation or above goes beyond minimum thermal requirements to maximize efficiency and comfort in your new home. While enhanced insulation does add modestly to new construction budgets, it certainly pays future dividends lowering heating bills for years to come.
Building professionals remain split, but best practices point to using R21 grade or better insulation paired with effective air-sealing solutions:
- Closed-cell spray foam seals effectively while adding insulation value
- Rigid foam boards supplement batt insulation coverage
Upfront investment in superior insulation beyond code minimums saves thousands down the road and adds resale value.
Home Renovations and Remodels
Major additions, basement finishes, and attic retrofits serve as prime opportunities to upgrade insulation during other renovations.
Leveraging existing demolition to enhance efficiency provides a big bang for your buck in the long run.
Just doubling existing batt insulation makes a measurable difference in energy savings. Tackling related air leakage and moisture intrusion issues while walls remain open further optimizes the thermal envelope.
Key areas to target insulation improvements:
- Attic ceilings under non-conditioned attic spaces
- Basement foundation walls, headers and rim joists
- Garage walls, ceilings and attic spaces
- Window and door headers lacking proper insulation density
Finding the Right Insulation Balance
Understanding insulation ratings equips you to make informed decisions about your home’s needs. However, products with higher R-values do not automatically perform better in every unique situation. In the same way, more horsepower or towing capacity does not necessarily make every vehicle ‘better’.
Ultimately you need adequate insulation for climate needs balanced with proper installation and air sealing.
Like a recipe, combining the right ingredients in proper portions and allowing them to work together results in optimal outcomes.
As you assess insulation upgrades, involve a reputable contractor like Phoenix Insulation Pros to evaluate your home holistically keeping efficiency, comfort and budgets equally in focus—ensuring just the right R-value where it counts most.
Key Takeaways: R13 vs R19 Insulation Comparison
- R-value measures resistance to conductive heat transfer; higher = better resistance
- R13 meets code minimum insulation for southern climate zones
- R19 provides a 30-50% higher R-value for northern heating dominant regions
- Framing, climate, budget and efficiency targets determine the ideal insulation
- Upgrade insulation wherever possible during remodels and additions
- Find the right insulation ‘ingredients’ for your climate and home construction recipe
