If you’re searching for the best 1 in insulation board, start with the job it needs to do. Ceramic fiber boards are designed for high-temperature insulation in equipment such as stoves, kilns, and forges, while Owens Corning 703 is a rigid fiberglass board suited to sound absorption and general thermal insulation. The picks below vary in material and size, so matching the board to your application matters more than choosing by thickness alone.
Table of Contents
Quick Comparison
| Product | Size | Key details | Best suited for |
|---|---|---|---|
| SIMOND STORE Ceramic Fiber Board | 1 × 18 × 24 in. | Rated up to 2300°F; density 20–24 lb/ft³ | High-heat projects needing a medium-size panel |
| Owens Corning 703 Fiberglass Board | 1 × 24 × 48 in.; 12 boards | R-value 4.3; NRC 0.7; Class A or Class 1 fire rating | Sound absorption and general insulation |
| Ceramic Fiber Board, 12 × 24 in. | 1 × 12 × 24 in. | Rated up to 2300°F; density 20–24 lb/ft³ | Smaller stove, kiln, or furnace projects |
| Ceramic Fiber Board, 19.7 × 39.4 in. | 1 × 19.7 × 39.4 in. | Rated up to 2300°F; density 20–24 lb/ft³ | Projects needing a larger single panel |
| Ceramic Fiber Board, 23.6 × 23.6 in. | 1 × 23.6 × 23.6 in. | Rated up to 2300°F; density 20–24 lb/ft³ | Square layouts and larger heat-shield areas |
Our Picks: Best 1 In Insulation Board reviews
SIMOND STORE Ceramic Fiber Board: A Versatile Panel for High-Heat Projects
This 1 × 18 × 24-inch aluminosilicate ceramic fiber board is made for high-temperature insulation. Its stated maximum use temperature is 2300°F, and the listed density is 20–24 lb/ft³. The compact panel size can be useful when you need a specific section of insulation rather than a large sheet.
The board can be cut with a knife or hacksaw blade and can also be drilled or machined. That makes it adaptable for stove baffles, fireplace insulation, pizza ovens, kilns, forges, and other applications named by the manufacturer. The listed compressive strength is 78 PSI at 25% deformation, but this is not a substitute for the strength of firebrick: the product information warns that the board dents easily.
Its balance of size and stated heat rating makes it a practical option for repairs and smaller builds. Before buying, measure the space carefully and confirm that the board’s rating and installation method suit your equipment. It is better viewed as an insulating component than as a load-bearing or impact-resistant surface.
Pros:
- Rated for use up to 2300°F.
- Useful 18 × 24-inch panel size for many repair jobs.
- Can be cut, drilled, or machined to fit.
- Listed for a wide range of heating equipment and insulation uses.
Cons:
- Can dent easily and is not as strong as firebrick.
- Check the dimensions before ordering if your project needs a larger or narrower panel.
Verdict: Choose this board if you need a 2300°F-rated ceramic fiber panel in a manageable 18 × 24-inch size and can protect it from impact.
Owens Corning 703: A Multi-Board Pack for Sound and Thermal Insulation
This pack contains 12 unfaced, semi-rigid fiberglass boards, each measuring 24 × 48 × 1 inch. The product data lists an R-value of 4.3 for heat-transfer reduction and an NRC of 0.7 for sound absorption. It also lists a Class A or Class 1 fire rating per ASTM E84 and an average of 53% recycled glass content.
The larger board format and multi-pack quantity can suit projects that need broad coverage, such as studio or building applications where sound absorption is a priority. Its listed acoustic rating distinguishes it from the ceramic fiber options here, which are intended for high-heat equipment. The supplied product information does not give this fiberglass board a 2300°F maximum-use rating, so don’t treat it as a replacement for refractory ceramic board in a stove, kiln, or forge.
Its main trade-off is that the pack may be more material than a small repair needs. Check the intended installation and applicable building requirements before choosing it, and follow the product’s handling instructions when cutting or fitting fiberglass boards.
Pros:
- Includes 12 large 24 × 48-inch boards.
- Listed R-value of 4.3 and NRC of 0.7.
- Class A or Class 1 fire rating per ASTM E84.
- Made with an average of 53% recycled glass content.
Cons:
- Not the right pick when you specifically need a ceramic board rated up to 2300°F.
- A 12-board pack may be more than a small project requires.
Verdict: Pick Owens Corning 703 for projects that call for rigid fiberglass insulation and sound absorption, not as a substitute for high-temperature ceramic fiber board.
12 × 24-Inch Ceramic Fiber Board: A Compact Choice for Tight Spaces
This single ceramic fiber board measures 1 × 12 × 24 inches. Like the other ceramic options in this list, it is made from aluminosilicate refractory material, has a stated maximum use temperature of 2300°F, and lists a density of 20–24 lb/ft³. The narrower width may be helpful for a smaller baffle, liner, or repair area.
The product information says it can be cut with a knife or hacksaw blade and drilled or machined to match an application. It lists a compressive strength of 78 PSI at 25% deformation and warns that the board is not as strong as firebrick. Plan for it to serve as insulation, not as a surface that must resist heavy knocks or support a load.
Compared with the 18 × 24-inch SIMOND STORE option, this board is narrower but has the same listed thickness, length, and heat rating. That smaller footprint may reduce excess material for a compact installation, though it could require more than one board for wider coverage. Confirm the required dimensions before ordering.
Pros:
- Rated for use up to 2300°F.
- Narrow 12-inch width may suit smaller spaces.
- Can be cut, drilled, or machined.
- Listed for stoves, fireplaces, ovens, kilns, and other heating equipment.
Cons:
- Smaller coverage area than the wider panels in this guide.
- Can dent and should not be treated like firebrick.
Verdict: This is a sensible option for a compact high-heat project where a 12-inch-wide panel is enough and the board will be protected from damage.
19.7 × 39.4-Inch Ceramic Fiber Board: More Coverage in One Panel
This ceramic fiber board measures 1 inch thick by 19.7 × 39.4 inches, making it the largest single panel in this group by area. Its stated maximum use temperature is 2300°F, with a listed density of 20–24 lb/ft³. A larger sheet can simplify coverage when your layout calls for a broad, continuous piece.
The board is described for use in wood stoves, fireplaces, pizza ovens, kilns, forges, and other heating equipment. It can be cut with a hacksaw blade or knife and may also be drilled or machined. The listed compressive strength is 78 PSI at 25% deformation, and the product data notes that it can dent easily, so careful handling and a suitable installation are important.
Compared with the smaller ceramic panels, this option offers more area in one piece, but it may be harder to fit into a compact workspace or transport through a tight opening. Measure the access route as well as the final installation area, and check whether a single large panel or smaller pieces make more sense for your project.
Pros:
- Largest single ceramic fiber panel in this selection.
- Rated for use up to 2300°F.
- Can be cut, drilled, or machined for a custom fit.
- Listed for a range of high-temperature insulation applications.
Cons:
- Large dimensions may be awkward for small installations or tight access.
- Can dent easily and is not a structural substitute for firebrick.
Verdict: Choose this panel when you need broad coverage from one 2300°F-rated ceramic fiber board and have room to handle and fit its larger dimensions.
23.6-Inch Square Ceramic Fiber Board: A Balanced Shape for Heat Shields
This single ceramic fiber board measures 1 × 23.6 × 23.6 inches. Its square shape offers a different layout from the long rectangular panels, which may be useful for a square floor section, front plate, or heat-shield area. The stated maximum use temperature is 2300°F, and the listed density is 20–24 lb/ft³.
The product information says the board can be cut with a knife or hacksaw blade, and can be drilled or machined. It lists a compressive strength of 78 PSI at 25% deformation but cautions that the board dents easily and is not as strong as firebrick. As with the other ceramic fiber choices, it is best treated as insulation rather than a durable exposed work surface.
Its square footprint provides more area than the 12 × 24-inch option, while taking up less length than the 19.7 × 39.4-inch panel. That can make it a useful middle ground if your project needs a broad section without an elongated sheet. Check the actual dimensions of the space before deciding.
Pros:
- Square shape can suit floor, front-plate, or heat-shield layouts.
- Rated for use up to 2300°F.
- Can be cut, drilled, or machined to fit.
- Listed for stoves, ovens, kilns, forges, and related applications.
Cons:
- Can dent easily and is not as strong as firebrick.
- May require cutting if your installation needs a rectangular panel.
Verdict: Select this board if your high-heat project benefits from a square panel with more coverage than the compact option but less length than the largest sheet.
How to Choose a 1-Inch Insulation Board
Match the material to the job
First decide whether you need high-temperature refractory insulation or sound and general thermal insulation. The ceramic fiber boards here are listed for use in heating equipment and have a stated maximum use temperature of 2300°F. Owens Corning 703 is a fiberglass board with listed sound-absorption and R-value details; the supplied information does not give it the same high-temperature rating. These materials are not interchangeable just because both are one inch thick.
Check the temperature rating and equipment requirements
For a stove, kiln, forge, or oven, confirm the board’s temperature rating against the requirements for your specific equipment and installation location. A maximum-use temperature is not, by itself, a complete installation specification. Follow the appliance and board manufacturer’s instructions, including any requirements for placement, protection, or other lining materials.
Measure the panel and the space
Compare the board’s width and length with the area you need to cover. A 12 × 24-inch panel can suit a narrow repair, while the 19.7 × 39.4-inch option provides more area in one piece. The 18 × 24-inch and 23.6 × 23.6-inch boards offer other layouts. Account for trimming, seams, and access when planning your cuts.
Consider strength and surface protection
Ceramic fiber board is an insulation product, not a replacement for firebrick where a hard, impact-resistant surface is required. The listed boards can dent easily. Consider how the board will be supported and whether the installation protects it from knocks or other damage. The Owens Corning 703 board has different material and use details, so assess it for the intended building or acoustic application rather than assuming it can serve as refractory lining.
Plan for cutting and handling
The ceramic boards are described as cuttable with a knife or hacksaw blade and suitable for drilling or machining. Fiberglass boards also need careful handling during fitting. Use appropriate protective equipment and follow the product’s handling instructions when cutting or machining any insulation material. Make a plan for clean, accurate cuts before starting.
Choose pack size and coverage carefully
Most of the ceramic choices listed are single boards, while the Owens Corning 703 listing includes 12 boards. A larger pack may suit a broad installation, but can be excessive for a small repair. Compare the total coverage you need with each board’s dimensions, and confirm the quantity included in the listing before ordering.
Frequently Asked Questions
Are all one-inch insulation boards suitable for high heat?
No. Thickness alone does not determine temperature suitability. The ceramic fiber boards listed here have a stated maximum use temperature of 2300°F. The supplied information for Owens Corning 703 gives an R-value, NRC, and fire rating, but not that same maximum-use temperature. Match the material and rating to the application.
Can ceramic fiber board replace firebrick?
Not where you need the strength of firebrick. The ceramic board descriptions specifically note that the material is not as strong as firebrick and can dent easily. Use it as insulation only where the installation calls for it, and follow the equipment manufacturer’s guidance.
Which ceramic board has the most coverage?
The 1 × 19.7 × 39.4-inch panel is the largest single ceramic board in this selection by area. The 23.6 × 23.6-inch panel is a broad square option, while the 18 × 24-inch and 12 × 24-inch boards are smaller.
Can these boards be cut to size?
The ceramic fiber board descriptions say they can be cut with a knife or hacksaw blade and can be drilled or machined. Plan your measurements before cutting, and follow the product’s handling instructions and appropriate safety practices.
Is Owens Corning 703 a ceramic fiber board?
No. The listing describes it as a semi-rigid fiberglass insulation board. It has different stated properties from the ceramic fiber boards, including an R-value of 4.3 and an NRC of 0.7. Choose it for an application that calls for fiberglass insulation and sound absorption, not simply because it is one inch thick.
How do I choose between the ceramic board sizes?
Measure the area you need to cover and consider the shape of the space. The 12 × 24-inch board is the narrowest option, the 18 × 24-inch board is a compact rectangle, the 23.6-inch square board offers a balanced footprint, and the 19.7 × 39.4-inch board provides the most coverage in one panel.
Final Recommendation
For high-temperature insulation, the SIMOND STORE 1 × 18 × 24-inch ceramic fiber board is a strong all-around choice because it combines a manageable size with a stated 2300°F maximum use temperature and can be cut to fit. Choose the 12 × 24-inch panel for tighter spaces, the square panel for a balanced footprint, or the larger 19.7 × 39.4-inch board for more coverage in one piece. If your priority is sound absorption or general fiberglass insulation, Owens Corning 703 is the better match—but it should not be treated as a substitute for a high-temperature ceramic board.
