R-19 Insulation Rolls
Wholesale fiberglass R-19 in 6.25" thickness. Vinyl-faced, foil-faced, or unfaced. The IECC minimum for walls in Climate Zones 3 and 4 — and the most-installed R-value in U.S. buildings.
What Is R-19 Insulation?
R-19 insulation is fiberglass batt or roll insulation rated at R-19 thermal resistance under ASTM C518, the testing standard the U.S. energy code uses to verify insulation performance. The number 19 represents the material’s resistance to heat transfer: the higher the R-value, the more the insulation slows the flow of heat in either direction. R-19 sits in the middle of the common residential and light-commercial R-value range, just above R-13 and just below R-25 and R-30.
Among fiberglass insulation products, R-19 is the single most widely installed R-value in the United States. The reason is dimensional: at a nominal installed thickness of 6.25 inches, R-19 fits 2x6 wall framing exactly — the framing dimension that gradually replaced 2x4 in code-conforming new construction over the past three decades. R-19 is also the IECC-recommended minimum for walls in Climate Zones 3 and 4, which covers most of the southern half of the country.
At Insulation Overstock we carry R-19 fiberglass insulation with every major NAIMA-certified facing: VR-R Plus, WMP-10, WMP-30, WMP-50, foil-faced, black-faced variants, and unfaced. Wholesale pricing ranges from $0.90 to $1.00 per square foot depending on the facing, with a buyer-offered service fee and factory-direct shipping to all 48 contiguous states.
R-19 Insulation Thickness and Composition
R-19 fiberglass insulation is manufactured by spinning molten glass into fine fibers, then binding the fibers into a low-density batt or roll. The result is a porous material that traps still air between fibers — and the trapped air, not the fiberglass itself, is what does the insulating work. Density and fiber orientation are tuned during manufacture to deliver consistent R-19 performance across the entire roll.
R-19 Nominal Thickness
R-19 fiberglass insulation has a nominal installed thickness of 6.25 inches. The word “nominal” matters here: the material can briefly compress during shipping or installation, but it must recover to 6.25 inches when installed to deliver its rated R-value. Compressed insulation loses thermal performance proportionally — an R-19 batt squeezed into a 5.5-inch cavity may only deliver R-15 or R-16. The full 6.25 inches is required.
R-19 Roll Dimensions
Common R-19 roll widths sold for metal buildings and pole barns are 4 feet, 5 feet, and 6 feet, with WMP-30 also available in 8-foot wide rolls. Roll lengths run from 16 feet up to 100+ feet depending on the project and shipping logistics. Standard square footage per roll varies by width: a 6-foot-wide, 50-foot-long roll covers 300 square feet.
Facing Options for R-19 Rolls
R-19 is available with every fiberglass insulation facing we sell, allowing buyers to match the facing to the building’s climate, humidity profile, and aesthetic preference. The full list is covered in the facing section below.
Where R-19 Insulation Works Best
R-19 Insulation by IECC Climate Zone
The International Energy Conservation Code (IECC) divides the United States into eight climate zones and publishes minimum insulation R-values for each zone’s walls, ceilings, and floors. R-19 features prominently in the southern half of the country and as a floor-insulation minimum nationwide.
| IECC Zone | Example States | R-19 Used For |
|---|---|---|
| Zone 1 | Southern FL, HI | Floors (above unconditioned) |
| Zone 2 | TX (south), FL, LA, AL (coastal) | Floors, often walls |
| Zone 3 | TX, GA, NC, AZ, CA | Walls (minimum) |
| Zone 4 | VA, TN, KY, MO, OK, NM | Walls (minimum) |
| Zone 5 | CO, OH, IL, NY, MA | Floors (R-25+ for walls) |
| Zone 6 | MN, MT, WI, ME, ND | Floors (R-25+ for walls) |
| Zone 7 | Northern MN, WI, ME | Floors (R-25+ for walls) |
| Zone 8 | Northern AK | Floors only |
For a complete breakdown of recommended R-values across all building surfaces and all eight climate zones, see the R-Value Guide by Climate Zone. The Department of Energy publishes the official IECC climate zone map; most of Colorado is Zone 5 or 6, the Gulf Coast is Zone 2, and northern Minnesota is Zone 7.
R-19 Insulation Cost Per Square Foot
Wholesale R-19 fiberglass insulation pricing at Insulation Overstock runs $0.90 to $1.00 per square foot depending on which facing the buyer selects. The difference between the lowest-priced facing (VR-R Plus) and the highest-priced (WMP-50 premium) is about 11 cents per square foot — meaningful on large commercial orders but negligible on residential projects.
- VR-R Plus (vinyl-reinforced PSP): $0.90 / sq ft
- WMP-10 (10-perm PSK): $0.96 / sq ft
- WMP-30 (30-perm heavy-duty): $0.96 / sq ft
- WMP-50 (50-perm PSKP metalized): $0.96 / sq ft
- Black-faced variants: $0.94 to $1.00 / sq ft
These are the manufacturer’s wholesale rates — the same rates we pay the certified mill. Add freight to your state (typically $0.10 to $0.18 per square foot for the lower 48) and your offered service fee within the published acceptable range (the range scales by order size from 3% to 30% of wholesale). There is no hidden markup on the material.
The fastest way to see your total R-19 cost is the Insulation Calculator: enter square footage, facing, R-19, and your state, and the calculator returns material cost, freight, and service fee as three separate line items. For larger orders, the Bulk Insulation page covers the $250 volume discount on material orders over $10,000.
Available Facings for R-19 Rolls
Every facing in the Insulation Overstock catalog is available in R-19. Selection is driven by climate humidity, building use, and aesthetic preference — not by R-value.
VR-R Plus (PSP) — Most Economical
VR-R Plus is the vinyl-reinforced general-purpose facing. It carries a vapor-retardant rating suitable for most U.S. climates and represents the value-priced choice for residential, agricultural, and light-commercial projects. In R-19, it is the most-ordered facing on this site.
WMP-10 (PSK-STD) — Standard Metal Building
WMP-10 carries a 10-perm rating — the standard for metal building wall systems. The facing is white polypropylene-faced and stronger than VR-R Plus, making it the practical choice for buildings with finished interiors where the facing is visible.
WMP-30 (PSK-HD) — Heavy-Duty, 8-Foot Available
WMP-30 is the heavy-duty version with a 30-perm rating, recommended for humid climates and commercial applications. It is also the only R-19 facing available in 8-foot wide rolls, which speeds installation on large pole barn and warehouse projects.
WMP-50 (PSKP) — Premium Metalized
WMP-50 is the premium 50-perm facing with metalized polyester backing. It has the highest tensile strength of any facing in the line and is the spec used in commercial warehouses, distribution centers, and aircraft hangars.
Black-Faced Variants
Black-faced fiberglass insulation in R-19 is available with VR Black, WMP-10 Black, and WMP-50 Black facings. Selection is typically aesthetic (the facing is the visible interior surface in many agricultural and commercial buildings) or for darker building interiors where white facing would create unwanted glare.
R-19 vs Other R-Values
Choosing between R-13, R-19, and R-25 is about matching insulation depth to framing depth, then verifying the result meets the climate zone’s code minimum.
| R-Value | Thickness | Best For | Wholesale Price/Sq Ft |
|---|---|---|---|
| R-13 | 3.625" | 2x4 wall framing | $0.65 – $0.75 |
| R-19 | 6.25" | 2x6 walls, Zone 3-4 walls | $0.90 – $1.00 |
| R-25 | 8.0" | Zone 5+ walls, ceilings | $1.13 – $1.23 |
| R-30 | 9.5" | Zone 4+ ceilings, attics | $1.36 – $1.42 |
Choose R-13 over R-19 when: framing is 2x4, the building is in Zone 1 or 2, or it’s an unconditioned outbuilding.
Stay with R-19 when: framing is 2x6, building is in Zone 3 or 4, or framing depth physically prevents going deeper.
Upgrade to R-25 or higher when: building is in Zone 5 or above, the building is heated year-round, or you’re insulating ceilings where deeper material fits without dimensional conflict.
R-19 Insulation FAQ
What is R-19 insulation?
R-19 insulation is fiberglass batt or roll insulation rated at R-19 thermal resistance per ASTM C518, the U.S. testing standard the energy code references. It is the most-installed R-value in U.S. residential and light-commercial construction, primarily because the 6.25-inch nominal thickness fits 2x6 wall framing exactly.
How thick is R-19 fiberglass insulation?
R-19 fiberglass insulation is 6.25 inches thick at nominal installed depth. The material can compress during shipping and handling but must recover to the full 6.25 inches in the installed wall, ceiling, or floor cavity to deliver its rated R-19 performance. Compressed insulation always loses thermal performance.
How much does R-19 insulation cost per square foot?
Wholesale R-19 fiberglass insulation runs $0.90 to $1.00 per square foot at Insulation Overstock, depending on the facing chosen. VR-R Plus is the lowest at $0.90; the WMP-10/30/50 line and black-faced variants range from $0.94 to $1.00. Freight and a flat service fee are itemized separately.
Is R-19 enough for a metal building?
R-19 meets the IECC minimum for metal building walls in Climate Zones 3 and 4 — roughly the southern half of the U.S. For Zones 5 through 7 (most of the northern U.S.), R-25 or higher is the code-required minimum for walls, and R-30 or higher is recommended for roof systems regardless of zone.
Can R-19 be installed in a 2x4 wall?
No — not without losing performance. A 2x4 wall cavity is 3.5 inches deep, and R-19 requires 6.25 inches to deliver rated R-19 performance. Forcing R-19 into a 2x4 cavity compresses it to about R-13. For 2x4 walls, order R-13 fiberglass insulation, which is dimensioned for that framing.
What climate zones recommend R-19 walls?
The IECC recommends R-19 as the wall minimum for Climate Zones 3 and 4 — covering Texas, Florida, Georgia, the Carolinas, Arizona, Tennessee, Virginia, Oklahoma, and most of the Mid-Atlantic and Pacific Southwest. North of Zone 4, R-25 or higher is preferred for walls; R-19 there typically serves only floor cavities.
Order R-19 Fiberglass Insulation
Enter your square footage and state to see wholesale pricing on R-19 in every available facing. Material cost, freight, and service fee are each itemized.
Price Calculator
Select your facing, R-value, square footage, and delivery state to see wholesale pricing instantly.
Add accessories and offer the Service Fee amount to complete order.