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160mm Heave Stopper Clayboard (Protection for Foundations)

160mm Heave Stopper Clay Heave Protection Board for Foundations 2400mm x 1200mm
160mm Heave Stopper Clayboard (Protection for Foundations)
  • Alternative to Dufaylite’s Clayboard and Cordek Cellcore
  • Construction Void Former Ground Heave Solutions
  • 160mm Heave Stopper 120kn/m2 - concrete thickness up to 1000mm
  • BBA approved 2400mm x 1200mm Honeycomb Board
  • Ground Beams, Slabs and Concrete Foundations
Estimated delivery:
In Stock
£ 118.63
Ex VAT: £ 98.86
  • Brand: WHITEROCK® Construction Products
  • Model: HS160 Heave Stopper
  • Dimensions: 2,400mm x 1,200mm x 160mm
  • SKU: HS160 Clay heave board
  • Product code: P1-2411
  • MPN: HS160

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160mm Heave Stopper Clayboard is a construction void former, an alternative to Dufaylite Clayboard and Cordek Cellcore that is suitable for Ground Beams and Slabs to protect foundations against ground movement.

Heavestopper 160mm is a BBA certified 2400mm x 1200mm environmentally friendly honeycomb board used to create a void underneath the foundation for ultimate stability in ground liable to ground heave.

Ground beams, slabs and concrete foundations can be subject to cracking as a result of the forces of ground movement when built on areas of shrinkable soil.

160mm Heave Stopper is an eco-friendly, recycled collapsible void former with maximum strength of 120kn/m2, that protects against ground movement whilst laying concrete foundations.

When the honeycomb core is introduced to water it is designed to lose its strength in order to permit ground heave without transmitting pressure to the foundations or structures above.

Heave Stopper 120kn/m2 is calculated and calibrated for concrete thickness up to 1000mm (the slimmest method of void creation means less excavation, muck away, vehicle movements and landfill).

The structural damage caused by clay is acknowledged by engineers and designers all over the world.

In the UK the problem is particularly acute in the South East, although climate change is having its effect on soils in other parts of the country.

Heave Stopper 160mm can also be used horizontally and vertically to create a void to protect structures from vibration.

Clay Heave Protection Board Heave Stopper is an easy to install and simple to work with and doesn't have much dust off when cut on site.

Shrinkage potential of HS160 (Heave Stopper 160mm) is classified as high with WHITE colour code and plasticity index between 40-60.

The board’s mechanical properties have been independently tested at the BRE Innovation Park. 

Tests show that the initial saturation procedure leaves just 10mm of material in the void zone.

Ultimately a 100% clear void is created which is in excess of the specified requirements and with zero kN/m2 of transmitted force.




Thickness: 160mm

Length: 2400mm

Width: 1200mm 

Board Coverage: 2.88m2

Strength: up to 120kn/m2


Heave Stopper Key points:

 · BBA Approved.

 · Easy to install.

 · FSC Approved.

 · Ideal for sites with restricted access.

 · Suitable for Ground Beams and Slabs.

 · Alternative to Dufaylite Clayboard.

 · Meets the technical requirements of the NHBC.

 · Alternative to Cordek Cellcore HX S Under Slab.

 · Lowest possible forces transmitted to the structure.

 · Alternative to Cordek Cellcore HX B Under Beam.

 · The slimmest method of void creation means less excavation.

 · Environmentally friendly, core facings manufactured from 100% recycled materials.

 · A perfect solution for contaminated land and brownfield sites.


Heave Stopper Storage:

The boards must be kept dry, stored off the ground and on the delivery pallets to prevent any moisture ingress whilst in storage.

Stacked pallets must not exceed 2 high.

The protective cover must not be removed until ready for use.


160mm Heave Stopper Installation:

Ensure that the area is free of surface water.

Heave Stopper must not be placed in waterlogged ground.

Lay a sand, shingle or concrete blinding to provide a level bed for the boards to rest on with no pressure points to the underside.

Lay minimum 125mu (500 gauge) polythene the full width of the excavation and tape all joints.

Pay attention to detailing around pile penetrations and corners to ensure a watertight seal.

Good practice requires that enough polythene is laid to fold over the Heave Stopper boards to lap with the top layer of polythene.

Position Heave Stopper boards.

Fold over the polythene from the bottom layer to the top face of the Heave Stopper boards and tape all joints.

Make provision to introduce water into the Heave Stopper boards by way of the Void Pipe.

A Void Pipe is required every 25m2 or for every isolated area of Heave Stopper.

Tie the Void Pipe to adjacent reinforcement to hold upright during concrete pour.

Pour concrete and allow enough time to elapse for the concrete to become self supporting.

Introduce water into the Heave Stopper boards by inserting a hose pipe into the Void Pipe.

Flood with enough water to ensure total saturation of the Heave Stopper.

Once the saturation process is complete, strike through the bottom facing and polythene to allow the water to drain.

Pipe sections can now be sealed off with cement or sealant.


*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



For more information:


Board covarage 2.88 m2
Colour Code: WHITE
Length 2400mm
Material Environmentally friendly honeycomb
Profile Residential & Commercial Grade
Thickness 160mm
Width 1200mm 
Coverage 2.88m2
Shipping method Courier
Grade Maximum strength grade of 120kn/m2
Applications Under Slab and Beams ǀ Foundations ǀ Ground Heave
BBA Certified Yes (no. 12/4963)
Maximum depth of concrete up to 1000mm thick (wet concrete)
Features Alternative to Dufaylite Clayboard & Cordek Cellcore
Shrinkage Category High
Manufacturer Whiterock Construction Products®
Plasticity Index 40-60

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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.
160mm Heave Stopper Clay Heave Protection Board for Foundations 2400mm x 1200mm
160mm Heave Stopper Clayboard (Protection for Foundations)
£ 118.63