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12mm RCM RenderFlex Render Carrier Fibre Cement Board

12mm RCM Renderflex A1 Render Carrier Board - Rendering Building Board - 8x4
12mm RCM RenderFlex Render Carrier Fibre Cement Board
  • Fire rated to EN 13501-1 class A2-s1, d0
  • Can be used in conjunction with Polymer Renders
  • Thin Coat Renders: Acrylic, Silicone, Silicone-Silicate...
  • Cellulose Fibre Cement - Internal and External Applications
  • Excellent Weathering Properties prior to Render Application
Estimated delivery:
In Stock
£ 126.10
Ex VAT: £ 105.08
  • Brand: RCM®
  • Model: 12mm RCM Renderflex A1
  • Weight: 47.88kg
  • Dimensions: 2,400mm x 1,200mm x 12mm
  • SKU: 12mm Render-flex
  • Product code: P1-2182
  • MPN: 12mm-RCM-Render-flex-Class A1

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12mm RCM Benx RenderFlex Render Carrier Board Class A2 is a fibre cement based stable render carrier board, used as base board for polymer modified renders and as an exterior brick and stone slip carrier board.

Renderflex render building board has been specially formulated to achieve a strong key between polymer basecoat and topcoat finish within external wall insulation systems.

The unique board structure offers a high tensile strength (ILB) essential for long term durability, whilst being developed to minimise board movement reducing any stress being applied to the external wall render systems.

Renderflex boards are suitable for the following construction types: lightweight steel frames, timber frames, modular, offsite and concrete frame.

RCM RenderFlex 12mm x 1200mm x 2400mm has one smooth face and one textured face, the smooth face should be fixed outermost.




Thickness: 12mm

Width: 1200mm 

Length: 2400mm

Board Coverage: 2.88m2

Density: 1380kg/m3

Thermal Conductivity: 0.12W/mk

Bending Strength: 17N/mm2

Surface Front Face: Smooth

Surface Back Face: Textured

Durability (Life Expectancy - Minimum): 30 years

Steel Frame Fixing: 4.8mm x 38mm Wing tip self drilling

Timber Frame Fixing: 4.2mm x 42mm Climaseal self drilling

Fire Reaction: BS EN 13501-1 Class A2


Key points:

 · High impact resistance.

 · High dimensional stability.

 · Maintains minimum board movement.

 · Reduced stress on rendered finish.

 · Integrates with other RCM products.

 · Fire rated to EN 13501-1 class A1-s1, d0.

 · Excellent weathering properties prior to render application.


Key applications:

 · Render carrier board.

 · For use with polymer renders.

 · Internal and external applications.

 · Fascia’s and soffit liner.


What applications can RCM Renderflex be used in?

 · RCM Renderflex is used as a Render carrier board for most polymer modified thin coat render systems.

 · RCM Renderflex can be used as an exterior brick and stone slip carrier board.


What is the fire rating of RCM Renderflex?

 · RCM Renderflex has a rating of A2 to EN13501-1 this is a reaction to fire classification and should not be confused with fire resistance.


Can RCM Renderflex be used as a permanently exposed external board?

 · No, RCM Renderflex cannot be left permanently exposed.


What are the fixing edge distance and maximum fixing centres for RCM Renderflex?

 · RCM Renderflex edge distance is 12mm except at the board corners where fixings should be moved up or down to achieve 50mm. 

 · Fixings should be fixed using a maximum 600mm x 300mm grid pattern.


How many fixings are required for RCM Renderflex?

 · 27 No. fixings per 2400mm x 1200mm sheet when fixed in a vertical orientation.

 · 25 No. fixings per 2400mm x 1200mm sheet when fixed in a horizontal orientation.


*Further information may be found in our Downloads section.

Fairly easy access to all PDF files.

Datasheet ǀ Declaration of Performance - DoP ǀ BBA Certificate ǀ Installation Guide ǀ Certificates ǀ Brochure ǀ SPEC Sheet

Board covarage 2.88 m2
Density 1380kg/m3
Length 2400mm
Material Cellulose Fibre-Cement
Profile Render Carrier Board
Thermal Conductivity 0.12W/mk
Thickness 12mm
Width 1200mm 
Bending Strength 17N/mm2
Fire Reaction Class A1
Coverage 2.88m2
Finish Smooth | Textured
Durability Minimum 30 years
Applications Polymer Thin-Coat Renders
Fixing method Self Drilling Fixings
Features Long term durability and stability
Manufacturer RCM Renderflex®

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We deliver insulation materials to Mainland UK only. Deliveries to Highlands, Northern Ireland, Isle of Wight etc.. might be possible at additional cost.
We offer free delivery on most of the orders above £300 (excluding VAT) (except special products - shipping cost via courier - products marked ''Request A Quote'')

Delivery of some insulation materials might be extended due to the current situation (Covid-19, stock shortages, allocations).
If you need materials quickly please contact us - we will do our best to help you source materials needed.

We do not deliver on weekends and bank holidays. Sometimes we can deliver on Saturdays - please check with us before placing the order.
If you need any further information please contact us tel. 02081910776

We can help to calculate price per m2 or linear meter (one meter in length) cost, please just contact us via phone 02081910776, email or live chat. Alternatively, you can work it out yourself quickly and easily: to get cost per meter square please divide price shown in orange area by ''Required area (m2)'' Example price of £28.80 divided by board coverage 2.88m2 = cost of £10.00 per m2.


No matter whether you choose a local installer or a national company, there’s a few tips to help you find the right installer for your home insulation improvements, such as asking for recommendations and making sure that they’re part of a certification scheme. This makes sure that they have the right skills and standards of workmanship to carry out the installation, and you can be sure that they know exactly what they are doing.


1. Thermal inspection picture in portfolio

It’s worth seeing a installer’s previous work. There’s no harm asking if you can see any properties nearby that they’ve installed insulation in. Best way would be to see Infrared Thermal Imaging Inspections. Thermal cameras spot small, but key changes in temperature in different areas of a house, identifying problematic areas that the human eye never could and some that a visual inspection could only hypothesize.

2. Reviews

Along with checking recommendations and previous work, finding reviews online can often be a great way to find out if they provide a good service or not. However, it’s best not to solely rely on reviews you may find or review websites, as there’s no controlling who writes them.

3. Compare prices

Comparing prices will also ensure companies can’t take advantage of you and give you a fair price. 

4. Word of Mouth

The best way to find a great insulation installer is through recommendations. Make sure you ask friends and family. They will most likely give you their honest opinion and can tell you from first hand experience.


Whether you require a wall, cladding, external wall, loft or floor insulation fitted, you can find and hire your local insulation installers from popular UK web pages. A simple internet search will return thousands of potential installers near your area.



We are the stockist of construction materials and related products for both trade and DIY from most recognizable brands in the UK like Cordek, RCM, Promat, Rockwool, Isover, Celotex, Xtratherm, Ursa, Low-E, Cedral, Kingspan, Dufaylite, British Gypsum, K-rend, Ecotherm, Iko enertherm, Kay-Metzeler, Terrawool to allow you to complete your insulation job on time at competitive prices and the highest standards.


Whether you are a large company or a DIYer, if you need a large amount of insulation materials, we can offer quantity discounts at the best prices. Please contact us and our friendly customer service will try to find the best and cheapest solutions for you. We value your time and we will try to deliver the products as soon as possible at a reasonable price to your construction site or house. The UK's leading insulation supplier near you and your needs. Price List available upon request.
12mm RCM Renderflex A1 Render Carrier Board - Rendering Building Board - 8x4
12mm RCM RenderFlex Render Carrier Fibre Cement Board
£ 126.10