Description
Two GENDERKA graphite ranges sit behind this shelf and their declared figures differ, so this page publishes the stricter set: 5.00 m²K/W of declared thermal resistance at 160 mm, with the competing declaration shown beside it and a purchasing instruction for confirming which range arrives on the pallet.
What Polystyrene EPS Grafit 160mm Delivers on a UK Solid Wall
Polystyrene EPS Grafit 160mm carries a declared thermal conductivity of 0.032 W/mK under EN 13163:2012+A1:2015, and at 160 mm that gives 5.00 m²K/W of declared resistance from a single bonded layer of a rendered wall. It is the second-deepest working thickness in the graphite-enhanced EPS insulation boards range, and the practical gain over 150 mm is 0.35 m²K/W for 10 mm of extra build-up.
A wall U-value is a calculation across the whole build-up, so 5.00 m²K/W is the input an assessor needs rather than the finished answer. Fitted as a single layer, it also keeps the wall to one bonding pass and one fixing pattern per elevation instead of doubling thinner boards.
- Deep solid-wall retrofit: brick and block walls where the target resistance is beyond what 100 mm reaches and no internal floor area can be lost.
- Reveal and junction continuity: thinner boards in the same declared range carry the detail on the same adhesive and the same declared λ.
- Programme work: one thickness across a portfolio keeps plug length, rasping and basecoat sequence consistent between plots.
Why Specifiers Fit the 160mm Graphite Board
Four declared properties decide this deep-renovation insulation board on a UK facade, and each is a line on the manufacturer's card rather than a marketing grade.
- Declared λD 0.032 W/mK: the graphite content lowers conductivity against standard white expanded polystyrene, so a given resistance arrives in less depth and reveals stay workable.
- 5.00 m²K/W declared at 160 mm: read from the declared resistance table rather than thickness divided by lambda, which is the only value the Declaration of Performance carries and the one a calculation will accept.
- Bending strength ≥ 75 kPa: the board stays flat while it waits between bonding and plugging, which matters when a full lift is bonded before any fixings go in.
- Tensile strength ≥ 80 kPa perpendicular to the faces: the property the adhesive beneath and the reinforced layer above both pull against.
- Thickness tolerance ± 1 mm: board-to-board steps stay small at depth, so the basecoat covers a flatter plane and rasping time drops across an elevation.
Declared Specifications Under EN 13163:2012+A1:2015
Every value below is copied from the GENDERKA EPS 032 Fasada Extra technical card W32FE and Declaration of Performance W32FE/ZCH/01/15, and belongs to the board as a product rather than to any wall it sits in.
| Declared property | Value |
|---|---|
| Thermal conductivity λD | 0.032 W/mK |
| Declared thermal resistance at 160 mm | 5.00 m²K/W |
| Reaction to fire (board) | Class E |
| Durability of reaction to fire | Class E, unchanged over time |
| Bending strength | BS75, ≥ 75 kPa |
| Tensile strength perpendicular to faces | TR80, ≥ 80 kPa |
| Thickness tolerance | T1, ± 1 mm |
| Length and width tolerance | L2 and W2, ± 2 mm |
| Squareness / flatness | Sb2, ± 2 mm/m / P5, ± 5 mm |
| Dimensional stability | DS(N)2, ± 0.2 % / DS(70,-)2, ≤ 2 % |
| Assessment route | System 3, ITB notified body 1488 |
Three readings worth correcting on this board. W2 is a width tolerance of ± 2 mm, not a water-absorption grade, and water absorption is declared NPD, so no absorption figure belongs on the page. Compressive stress and freeze-thaw resistance are also NPD — undeclared rather than poor. Class E is the board's own reaction to fire and is never the classification of a finished wall; where a fire strategy calls for non-combustible insulation, the trade-offs at these depths are set out in the graphite EPS and mineral wool facade comparison.
How to Confirm Which Declared Range You Are Fitting
GENDERKA declares two graphite facade ranges that look identical on a pallet and differ on paper, and the previously published version of this page carried the EPS 031 figures. Renders World leads on the stricter declaration and shows both, so a specifier can see exactly which line the file rests on.
| Declared property | EPS 032 Fasada Extra (published above) | EPS 031 Fasada Extra Plus |
|---|---|---|
| λD | 0.032 W/mK | 0.031 W/mK |
| Resistance at 160 mm | 5.00 m²K/W | 5.15 m²K/W |
| Bending strength | ≥ 75 kPa | ≥ 100 kPa |
| Tensile strength | ≥ 80 kPa | ≥ 100 kPa |
| Reaction to fire (board) | Class E | Class E |
| Card number to look for | W32FE | W31FEP |
Ask the trade desk to confirm the card number and the producing plant on the order, then take the Declaration of Performance from the delivery paperwork for the assessment file. Both ranges are declared separately from five GENDERKA plants, so the DoP is settled at order rather than lifted from a listing — a step worth getting right where the file will be audited later.
How to Install the 160mm Board in an EWI Build-Up
Fitting Polystyrene EPS Grafit 160mm follows the manufacturer's card, and three of its instructions are specific to grey graphite boards rather than general good practice.
- Bond with an adhesive dedicated to grey graphite boards — cement-based, polyurethane foam, or water-dispersion bitumen — from the EPS adhesives basecoats range. Nothing containing organic solvents goes near the boards.
- Rasp or sand the bonding face immediately before bedding, which the card recommends specifically to raise adhesion of the mortar to the factory skin.
- Keep the boards out of direct sunlight, briefly and long term, in the stack and on the scaffold; the card is explicit that the steel-grey face must be shielded during storage and installation.
- Wait a minimum 24 hours after bonding before plugging. Fixings then go in from the insulation fixing accessories range, to the plug length and density the fixing manufacturer's own selection table gives for the substrate.
- Build the reinforced layer next, embedding mesh from the rendering mesh range before the finish coat.
Layout is a manufacturer and system figure rather than a rule of thumb, and the patterns UK installers work to are set out in the board fixing pattern and spacing guide; the full sequence and drying intervals sit in the EWI system build-up guide. On handling, the listing declares a shipping weight of 1.2 kg per board, so single-handed positioning at scaffold height stays comfortable at this depth.
How the 160mm Board Compares With Its 150mm and 180mm Siblings
All three thicknesses share one declaration, so the comparison is a straight read of the same declared table.
| Board | Declared resistance | When it is the right depth |
|---|---|---|
| 150 mm graphite board | 4.65 m²K/W | Deep retrofit where reveals are tight |
| 160 mm (this board) | 5.00 m²K/W | Deep renovation with resistance headroom |
| 180 mm graphite board | 5.60 m²K/W | Maximum fabric depth on masonry |
Stepping up from 160 mm to 180 mm buys 0.60 m²K/W for another 20 mm of build-up, against 0.35 m²K/W for the 10 mm step from 150 mm. That arithmetic is what usually settles window reveals, sill depth and verge detailing. How declared resistance becomes a wall U-value is set out in the U-value and insulation thickness calculation guide.
Choosing 160mm for Your Project
- Specify 160 mm when the calculation needs 5.00 m²K/W from one layer and reveals, sills and verges can absorb the depth.
- Step down to the 150 mm graphite board where 4.65 m²K/W satisfies the calculation and the detailing budget is tighter.
- Check the fire strategy first on anything beyond low-rise housing; the board's own class is E and the designer decides what the completed wall requires.
- Model the moisture path on solid walls before committing to depth, using the dew point and condensation risk guide, and read the direction of travel in the Future Homes Standard 2026 guide.
What the 160mm Board Costs and What to Order Alongside It
Polystyrene EPS Grafit 160mm is listed at £11.20 per 1000 × 500 mm board, fetched August 2026, and the listing showed it available on that date. At 0.50 m² of face area per board that works out at £22.40/m² for the insulation layer alone, before adhesive, basecoat, mesh, fixings and the finish coat. The listing displays no VAT label, so confirm the VAT treatment on the invoice.
- Take off by board, not by pack: 80 m² of net wall ÷ 0.50 m² per board = 160 boards, plus 10 % for cutting around reveals and penetrations = 176 boards.
- Price the layer, then the system: 176 boards × £11.20 = £1,971.20 of board at the listed figure, materials only, with the other layers quoted separately.
- Confirm format and pack on the order: the manufacturer card covers other board sizes, so the 1000 × 500 mm format supplied here is confirmed against the delivery note rather than the datasheet.
Renders World quotes the whole build-up on one consolidated order, and the trade desk confirms pallet quantities and delivery before anything leaves the warehouse.
FAQ — 160mm Coverage, Fixings, Limits and Fire
How many boards cover 100 m² of wall?
Each board presents 0.50 m², so 100 ÷ 0.50 = 200 boards, plus 10 % for cutting waste = 220 boards. Confirm the pack format against the delivery note before a programme order is placed.
Which adhesive and plug suit a 160 mm graphite board?
Adhesive must be one of the three types the manufacturer names for grey graphite boards: cement-based, polyurethane foam, or water-dispersion bitumen. Plug length and density come from the fixing manufacturer's selection table for the substrate and board depth, which is why no length is quoted here.
Is 160 mm or 180 mm the better choice?
Declared resistance rises from 5.00 to 5.60 m²K/W across that 20 mm step. Where the calculation lands inside 5.00 m²K/W, the slimmer board keeps reveal and sill detailing simpler; where it does not, 180 mm is the next declared point in the same range.
What limits apply during storage and installation?
Three declared limits: shield the grey faces from direct sunlight at all times, keep organic solvents and their vapours away from the boards, and leave at least 24 hours after bonding before mechanical fixing.
Does the class E board set the wall's fire performance?
Class E is declared for the board on its own, and the declaration records that class as unchanged over time. A finished external wall is classified as a build-up under the project fire strategy, so a board class is never carried onto the completed facade.
Technical Documentation — Declared Performance Sheets
All four documents below were retrieved live for this page.