Are hardie board and Masonite the same thing?

No, Hardie Board and Masonite are not the same thing, they are completely different materials with different compositions, durability, and uses, though both are used for siding. Hardie Board is the common name for James Hardie HardiePlank, which is fiber cement siding made from cement, sand, cellulose fibers, and water, pressed and cured to form a durable, rot-proof, fire-resistant siding that mimics wood. Masonite is a brand of hardboard, which is engineered wood made from compressed wood fibers with heat and pressure, without cement. Masonite hardboard siding was popular in the 1980s and 1990s but was discontinued after class-action lawsuits because it absorbed moisture, swelled, and rotted. Hardie Board is far superior in durability, lasting 30 to 50 years, fire resistant, insect proof, and holds paint well, while Masonite hardboard siding lasted 10 to 20 years and failed in moisture. Hardie Board is heavier, more expensive at 10 to 18 dollars per square foot installed versus Masonite siding which was cheaper, and requires special tools to cut due to silica dust. Both can look like wood lap siding, but Hardie Board is cement-based and Masonite is wood fiber-based. So they are not same, Hardie Board is fiber cement, Masonite is hardboard wood fiber, and Hardie Board is considered premium replacement for failed Masonite siding.

No, Hardie board and Masonite are not the same thing, they are completely different building materials, with Hardie board being fiber cement siding made from cement, sand, and cellulose fibers, and Masonite being hardboard or wood fiber siding made from pressed wood fibers, differing in composition, durability, and performance. Hardie board is brand name for James Hardie fiber cement siding, invented by James Hardie company, made from Portland cement, sand, water, and cellulose wood fibers, pressed into siding planks and panels, non-combustible, rot-proof, insect-proof, highly durable, resistant to moisture, fire, and termites, with 30 to 50 year warranty, used for exterior siding, priced around 1 to 3 dollars per square foot material, heavier and requires special cutting tools, popular as premium siding replacing wood. Masonite siding is hardboard siding made from wood fibers pressed with resin and wax, also called hardboard siding, popular in 1970s and 1980s as low-cost wood alternative, but prone to moisture damage, swelling, delamination, and rot when exposed to water, leading to class action lawsuits in 1990s, with shorter lifespan 10 to 20 years if not maintained, lighter, cheaper around 0.5 to 1.5 dollars per square foot, but less durable, now largely discontinued for exterior siding due to failure issues, though Masonite brand now focuses on doors. So Hardie board and Masonite are not same, Hardie is fiber cement durable siding, Masonite is wood fiber hardboard prone to moisture damage, with Hardie being superior modern replacement for failed Masonite siding, with different composition and performance.