Description
This is the Frontrock Plus 80mm slab: ROCKWOOL’s single-density stone wool board for external wall insulation under thin render, here in the thickness that suits a full elevation where 80 mm is the depth available. A pack of five 1000 × 600 mm slabs covers 3 m². It is one of six slabs in the Renders World mineral wool insulation range.
Where the Frontrock Plus 80mm Slab Fits
At 80 mm Frontrock Plus declares 2.25 m²K/W. That makes it a main-wall slab for walls where depth is limited — under deep sills that cannot be extended, along a boundary, or on a solid brick wall where you want a vapour-open layer without a deep build-up.
- Whole elevations of brick, block or concrete finished with a render system.
- Solid masonry walls, where the open structure lets the wall dry outwards; the solid-wall retrofit guide covers the wider job.
- A step up from the 50 mm slab where reveals or junctions can take a little more depth.
Why Choose Frontrock Plus at 80 mm
- More resistance than Super at the same depth. Plus declares λD 0.035 W/mK and 2.25 m²K/W at 80 mm; Frontrock Super at 80 mm declares 0.036 and 2.20.
- A1 slab. The slab is declared Euroclass A1, and ROCKWOOL states its fire performance does not fall away with age.
- Vapour-open. Class MU1 lets moisture keep moving out of the wall.
- Firm under render. CS(10)20 and TR10 give 20 kPa in compression and 10 kPa across the face.
- Five slabs per pack, 3 m². Bigger packs than the Super 80 mm, which comes three to a pack.
Frontrock Plus 80 mm Specification
| Property | Declared value |
|---|---|
| Product | ROCKWOOL FRONTROCK PLUS, 80 mm |
| Slab build | Stone wool, single density |
| Slab size | 1000 × 600 × 80 mm |
| Declared thermal conductivity λD | 0.035 W/mK |
| Declared thermal resistance RD | 2.25 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(70,90) |
| Thickness tolerance | T5 |
| Pack | 5 slabs, 3.0 m² |
| Maker's pallet | 12 packs, 36 m² |
| Standard and declaration | EN 13162:2012+A1:2015 · DoP RW-CEE-DoP-0238/BCM/23/w1 |
Declared in DoP RW-CEE-DoP-0238/BCM/23/w1 (ROCKWOOL Polska, Cigacice, EN 13162, notified body 1023). The declared 2.25 m²K/W is the value for a U-value calculation.
Fitting the 80 mm Slab
Bond the slabs with Roker U grey adhesive, which covers mineral wool facade slabs and the reinforced layer over them. Its data sheet sets the order.
- Skim the slab face thin with adhesive, apply the bonding coat and comb it with a 10 × 10 mm notched trowel; allow about 4.5–5.5 kg/m².
- Press each slab home and tap it level, keeping the vertical joints staggered.
- From the day after bonding, fix with galvanised metal-pin anchors, at least four per m² or as the insulation design requires; the fixing pattern and spacing guide shows typical layouts.
- After three days, build the mesh layer: two thirds of the mortar, mesh pulled taut into it, then the final third.
Every Frontrock Slab Side by Side
| Slab | Density | Declared RD | Pack |
|---|---|---|---|
| Frontrock Plus 50 mm | single | 1.40 m²K/W | 6 slabs · 3.6 m² |
| Frontrock Plus 80 mm (this slab) | 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 | 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 |
At 80 mm the shop carries both lines. Plus has the lower conductivity and larger packs; Super has a harder top layer that ROCKWOOL builds in to protect the facade from mechanical damage. Both declare the same compressive and tensile classes.
Ordering: Packs and What Goes With Them
Divide the wall area by 3 m² for the number of packs and round up for cuts around openings. ROCKWOOL palletises this thickness 12 packs, 36 m², to a pallet. Order the adhesive at the same time: Roker U bonds the slabs and forms the reinforced layer, so a single product covers both stages.
Is 80 mm Frontrock Plus Right for Your Wall?
- Yes for a main elevation where 80 mm is the depth you have and you want the most resistance from it — that is the Frontrock Plus 80mm.
- Take the Frontrock Super 80 mm where the facade is likely to take knocks and a harder outer layer matters more than the small difference in resistance.
- Go deeper with the Super range when the U-value calculation asks for more than 80 mm.
FAQ — Frontrock Plus 80 mm
How many packs do I need?
One pack covers 3 m² with five 1000 × 600 mm slabs. Divide the wall area by three and round up, leaving extra for cuts at openings.
What is the difference between Plus and Super?
Plus is single-density with λD 0.035 W/mK; Super is dual-density with λD 0.036 and a harder top layer. At 80 mm Plus declares 2.25 m²K/W and Super 2.20.
What adhesive and base coat go on it?
Roker U grey does both: it bonds mineral wool facade slabs and forms the mesh-reinforced layer on them, with the render system applied over that.
What U-value will 80 mm give?
That depends on the whole wall, not the slab alone. Enter the declared 2.25 m²K/W with the other layers; the U-value calculation guide shows the method.
Is the finished wall A1?
A1 is declared for the slab itself. The rendered wall is classified as a system, so its class comes from the system documentation, not from the slab.
What should I check on delivery?
The label should name FRONTROCK PLUS and 80 mm, and the declaration number RW-CEE-DoP-0238/BCM/23/w1 should match the one linked below.