Description
A dual-density stone wool slab for insulating the outside of a house and rendering straight over it. The harder outer face takes the render and stands up to knocks, the softer core does the insulating, and the slab will not burn. It lets the wall breathe, which suits older solid walls as much as new block.
Where Frontrock Super 100mm Fits
This is the Frontrock Super 100mm slab from ROCKWOOL, made for external thermal insulation composite systems — insulation bonded and anchored to the wall, then reinforced and rendered. At 100 mm it declares 2.75 m²K/W. It belongs to the Renders World mineral wool insulation range, where the Super line runs from 80 to 160 mm.
- Main elevations of brick, block or concrete, new or existing, finished with a thin render system.
- Solid walls in older houses, where a vapour-open layer lets the masonry keep drying; the solid-wall retrofit guide sets out the wider job.
- Busy facades — ground floors, paths and play areas — where the harder face is worth having.
If you are still weighing stone wool against polystyrene, the mineral wool against polystyrene comparison sets the two side by side.
Why Choose Frontrock Super at 100 mm
- Built in two densities. ROCKWOOL puts the compressibility of the hardened top layer at about 40 kPa and describes it as protecting the render from knocks during fitting and in use.
- A1 slab. The slab is declared Euroclass A1, and the declaration states that stone wool’s fire performance does not deteriorate with time.
- Vapour-open. Class MU1 — vapour passes through almost as freely as through air.
- Water-repellent. No more than 1.0 kg/m² short-term and 3.0 kg/m² long-term water absorption is declared.
- Dimensionally stable. DS(70,−) and DS(70,90) are declared, so joints stay tight under the base coat.
- Strong enough to carry render. CS(10)20 and TR10: 20 kPa in compression, 10 kPa perpendicular to the face.
- Thermal value that does not fade. The declaration states the conductivity of stone wool does not change with time.
Frontrock Super 100 mm Specification
| Property | Declared value |
|---|---|
| Product | ROCKWOOL FRONTROCK SUPER, 100 mm |
| Slab build | Stone wool, dual density, harder top layer |
| Slab size | 1000 × 600 × 100 mm |
| Declared thermal conductivity λD | 0.036 W/mK |
| Declared thermal resistance RD | 2.75 m²K/W |
| Reaction to fire (the slab) | Euroclass A1 |
| Compressive strength at 10 % deformation | CS(10)20 — 20 kPa |
| Tensile strength perpendicular to faces | TR10 — 10 kPa |
| Short-term water absorption | WS — up to 1.0 kg/m² |
| Long-term water absorption | WL(P) — up to 3.0 kg/m² |
| Water vapour diffusion resistance | MU1 |
| Dimensional stability | DS(70,−) and DS(70,90) |
| Thickness tolerance | T5 |
| Pack | 3 slabs, 1.8 m² |
| Maker's pallet | 16 packs, 28.8 m² |
| Standard and declaration | EN 13162:2012+A1:2015 · DoP RW-CEE-DoP-0237/BCM/23/w1 |
The performance values are declared in DoP RW-CEE-DoP-0237/BCM/23/w1, issued by ROCKWOOL Polska at Cigacice under EN 13162 with notified body 1023. For a U-value calculation use the declared 2.75 m²K/W; the U-value calculation guide explains the sum.
Installing the Slab Behind Render
Roker U grey adhesive is the cement-based adhesive for stone wool in the range: it bonds mineral wool facade slabs up to 30 cm thick and forms the reinforced layer. Its data sheet gives this order:
- Skim and comb. Work a thin coat into the slab face, apply the bonding layer and comb it with a 10 × 10 mm notched trowel; plan on about 4.5–5.5 kg/m².
- Set and tap, staggering the vertical joints from course to course.
- Anchor from the next day, with galvanised metal-pin anchors, at least four per m², the final number set by the insulation design. The guide to installing insulation fixings covers the drilling.
- Mesh after three days: two thirds of the mortar, glass-fibre mesh pulled taut into it, the last third over the top.
- Diagonal strips at openings: mesh pieces of at least 20 × 35 cm at 45° under the main layer at each corner.
Thickness Options Across the Frontrock Range
| Slab | Density | Declared RD | Pack |
|---|---|---|---|
| Frontrock Plus 50 mm | single | 1.40 m²K/W | 6 slabs · 3.6 m² |
| Frontrock Plus 80 mm | single | 2.25 m²K/W | 5 slabs · 3.0 m² |
| Frontrock Super 80 mm | dual | 2.20 m²K/W | 3 slabs · 1.8 m² |
| Frontrock Super 100 mm (this slab) | dual | 2.75 m²K/W | 3 slabs · 1.8 m² |
| Frontrock Super 120 mm | dual | 3.30 m²K/W | 3 slabs · 1.8 m² |
| Frontrock Super 160 mm | dual | 4.40 m²K/W | 2 slabs · 1.2 m² |
The 100 mm and 120 mm Super slabs share the same pack of three slabs, 1.8 m². Frontrock Plus is the single-density line with slightly lower conductivity, sold here at 50 and 80 mm.
Ordering: Packs, Pallets and Components
Divide the net wall area by 1.8 m² and round up, adding extra for the cuts around windows and doors. ROCKWOOL palletises this thickness 16 packs, 28.8 m², to a pallet. Order the Roker U adhesive in the same delivery so bonding and the mesh layer can follow on without a gap.
Is 100 mm the Right Thickness?
- Yes for a main elevation where the calculation lands at about 2.75 m²K/W — the Frontrock Super 100mm slab’s declared value.
- Take the 120 mm or 160 mm Super when more resistance is needed and the sills and roof edges allow it.
- Take the Frontrock Plus 50 mm for reveals and soffits around the openings in the same wall.
FAQ — Frontrock Super 100 mm
How much does one pack cover?
Three slabs of 1000 × 600 mm, 1.8 m² in total.
Which adhesive goes with it?
Roker U grey: it bonds mineral wool facade slabs and forms the reinforced layer, so the same product covers both steps.
Is the slab non-combustible?
Yes — Euroclass A1 is declared for the slab. A finished wall is classified as a whole system, which the facade fire requirements briefing explains.
What is the R-value of the 100 mm slab?
The declared thermal resistance is 2.75 m²K/W, with a declared conductivity of 0.036 W/mK.
Can the slabs be rained on before rendering?
Declared water uptake is low — up to 1.0 kg/m² short term and 3.0 kg/m² long term. Keep packs covered and render only once the slab face is dry.
Does it help with noise?
ROCKWOOL lists acoustic insulation among the slab’s features. For a sound-insulation target, ask for a tested result for the complete wall build-up.
Technical Documents — Frontrock Super