The choice between rigid board and wired roll of rock wool is no mere nuance: each format is calibrated for a different geometry. The board fits flat surfaces (partitions, suspended ceilings, dry-construction façades); the wired roll adapts to curved surfaces and complex geometries (industrial pipes, boilers, cylindrical tanks). This comparison of the two MOLTEXO rock wools helps you decide which one fits your thermal, acoustic or passive-safety insulation project.
🎯 Choose in 10 seconds
- If you are thermally or acoustically insulating partitions, suspended ceilings or flat façades in dry construction, residential or commercial: go to Rock wool board
- If you are thermally insulating industrial pipes, boilers, cylindrical tanks or other curved surfaces in an industrial plant: go to Wired roll
What to consider before choosing
Before buying, assess these four criteria. They determine whether the rock wool fulfills its thermal, acoustic or passive-safety insulation function for decades, or whether it loses performance over time.
- Type of surface to insulate: flat surfaces in residential or commercial construction (partitions, suspended ceilings, façades with steel framing, drywall) → board; industrial curved surfaces (large-diameter pipes, boilers, furnaces, cylindrical tanks, chimneys) → wired roll. The geometry of the substrate defines the format; using rigid board on a curved pipe does not fit, and using a roll on a flat partition wastes capacity.
- Main function of the insulation: three functions partially overlap: thermal insulation for comfort in a Caribbean climate (both board and roll deliver), acoustic insulation against noise between rooms (board fits better in a partition), and passive fire safety (both, thanks to their non-combustible A1 class). Define which is the dominant function before choosing.
- Environmental and mechanical exposure: the board is confined between two plasterboard sheets or behind a façade cladding, which protects the material from direct moisture and handling. The wired roll on an industrial site is exposed to steam, condensates, dust and handling during maintenance, which requires the structural support of the stitched galvanized net that prevents detachment.
- Density and auditable performance: both MOLTEXO formats have a declarable and verifiable density of 100 kg/m³ (6.24 pcf), a distinctive condition compared with generic mineral wools that promise density but deliver lower real performance. The calibrated density is what separates an auditable professional insulation from an economy mineral wool that does not perform as declared.
Rock wool board: insulation for flat surfaces
- Verifiable density of 100 kg/m³ for superior acoustic insulation
- A1 non-combustible fire resistance (melting point >1000°C)
- Three thicknesses: 50, 75, 100 mm (packs of 6, 4, 3 boards)
- Hydrophobic and vapor-permeable (no hidden mold in a humid climate)
- Dimensional stability with no settling for decades
- Only suitable for flat surfaces (not curved)
- Handle with gloves and a mask due to mineral fiber
Semi-rigid board of MOLTEXO volcanic rock wool with a density of 100 kg/m³ (6.24 pcf), 120×60 cm (47×23 in) format, available in three thicknesses (50, 75, 100 mm; 2, 3, 4 in). Designed for filling plasterboard (sheetrock) dividing partitions and steel-framing structures in residential and commercial settings; insulation above suspended ceilings and soffits against tropical-rain and upper-floor noise; façade linings for thermal insulation in a Caribbean climate with high solar incidence; enclosures requiring passive fire safety (machine rooms, emergency exits, fire-break separators).
Wired rock wool roll: industrial insulation for curved surfaces
- Density 100 kg/m³, thickness 50 mm, roll 0.6 × 5 m (2 × 16.4 ft)
- Galvanized net stitched on one face (structural support)
- Adaptable to cylindrical surfaces and complex geometries
- A1 non-combustible class (melting point >1000°C)
- Chemical stability with metals (non-corrosive)
- Industrial application (does not fit a flat partition)
- Handle with gloves and a mask due to fiber and net
Rock wool roll with stitched galvanized net (wired mat / reinforced blanket) MOLTEXO with a density of 100 kg/m³ (6.24 pcf), 50 mm (2 in) thickness, 0.6 m × 5 m (2 × 16.4 ft) format. Designed for insulation of large-diameter industrial pipes and ventilation ducts with a cylindrical surface; boilers, furnaces, steam generators and thermal equipment with curved surfaces or complex geometry; storage tanks, cylindrical vessels and industrial chimneys requiring continuous thermal insulation; acoustic insulation in machine rooms, pump rooms and noisy industrial areas.
Comparison table
| Feature | Board | Wired roll |
|---|---|---|
| Geometry | Flat surfaces | Curved and flat surfaces |
| Density | 100 kg/m³ (6.24 pcf) | 100 kg/m³ (6.24 pcf) |
| Thickness | 50, 75, 100 mm (2, 3, 4 in) | 50 mm (2 in) |
| Format | Board 120×60 cm (47×23 in) | Roll 0.6 × 5 m (2 × 16.4 ft) |
| Structural support | — | Stitched galvanized net |
| Main application | Dry construction, façades | Industrial: pipes, boilers, tanks |
| Reaction to fire | A1 non-combustible | A1 non-combustible |
| Brand | MOLTEXO | MOLTEXO |
Use-case matrix → recommended product
| If your case is… | Recommended product |
|---|---|
| Sheetrock dividing partition with acoustic insulation between rooms | → Rock wool board |
| Suspended ceiling with insulation against rain and upper-floor noise | → Rock wool board |
| Façade lining for thermal comfort in a Caribbean climate | → Rock wool board |
| Machine room requiring passive fire safety | → Rock wool board |
| Steel framing on a residential or commercial site with integrated insulation | → Rock wool board |
| Insulation of industrial steam or hot-fluid pipes | → Wired roll |
| Boiler, furnace or steam generator with a curved surface | → Wired roll |
| Cylindrical storage tank with continuous thermal insulation | → Wired roll |
| Industrial chimney or ventilation duct with complex geometry | → Wired roll |
| Industrial machine room with acoustic insulation of rotating equipment | → Wired roll |
Before buying, define two data points: the geometry of the substrate (flat or curved) and the dominant function (thermal, acoustic or passive safety). The practical rule: partition, suspended ceiling, façade lining, steel framing → board; pipe, boiler, cylindrical tank, chimney → wired roll. For projects with several zones (an industrial plant with adjacent offices) both formats are combined: board in the offices and roll in the process areas.
Do not use rigid board on a curved pipe or on a cylindrical surface — the board cracks with deformation, does not fit the geometry and leaves open thermal bridges that ruin the insulation. Conversely: do not use a wired roll on a flat sheetrock partition — the galvanized net complicates the enclosed installation, adds no extra value on a flat surface and wastes budget compared with the specific board.
All compared products
Frequently asked questions
Can I use the board instead of the roll for a large-diameter pipe?
It is not viable. The rigid board does not deform to adapt to a curved surface, and cutting it into wedges to wrap a pipe leaves thermal bridges at every joint that compromise the insulation. The stitched net of the roll is designed precisely so the wool molds to the curvature without losing the declared thickness.
Does rock wool lose performance with the Caribbean's ambient humidity?
The hydrophobic treatment of the MOLTEXO product repels liquid water without losing vapor permeability, which prevents moisture accumulation by capillarity in the Dominican climate. The insulating performance is maintained for decades as long as the installation respects the exterior vapor barrier and the joints remain sealed.
Does rock wool itch like fiberglass?
Rock fibers are thicker and less abrasive than fiberglass fibers, which reduces the itching sensation on skin and airways. Even so, handling with gloves, a mask and long sleeves is recommended to avoid skin and respiratory irritation during cutting and installation, especially in suspended ceilings where the fiber falls onto the operator.