Advantages of SureCav

KEEP 100mm overall cavities and achieve 0.18 EASILY

  • Cheaper, faster, sustainable and space saving!
  • Protection from wind-driven rain and water ingress
  • BBA approved for use in all exposure zones

SureCav25

SureCav25 is a moulded, 100% recycled, polypropylene panel with spacer protrusions, forming a 25mm clear cavity and providing the perfect backing board for the stone, slate, brick and flint outer leaf. It is a sixth of the CO2 footprint, compared to using a concrete block backing wall and is fully BBA certificated. This cavity protection system ensures clean and moisture free cavities with either timber frame or traditional construction. Panel size: 1200mm (L) x 450mm (H) x 25mm deep. Yes! Just 25mm deep. This also gives the option for more room in the cavity for insulation, enhancing the thermal performance of the building envelope.

  • Lowers U-Values by making more room for extra insulation
  • Option to increase internal room space
  • Half the cost of building a block supporting wall
  • 25mm permitted residual cavity
  • Maintains an essential air gap
  • Fully BBA certificated
  • Suitable for use with brick, stone, flint or slate external finishes
standing infront of SureCav, 100% recycled cavity spacer rainscreen system, behind is insulation and traditional build in a partial fill cavity. The SureCav25 and 50 are both BBA approved for use in any exposure zone, offering protection against wind-driven rain and moisture issues.

Significant cost savings

SureCav25 forms a 25mm clear cavity providing a backing board for the stone, slate, brick and flint outer leaf. It halves the cost of building with a backing block and produces a sixth the CO2 footprint, compared to using a concrete block backing wall and is fully BBA certified. 

Gain more space with SureCav25!

A reduction in wall thickness of 25mm will increase the internal dimensions of the property by 50mm in each direction and result in an average of 1.6% increased floor space. Already more floor space will have been gained by removing the need for 100mm concrete backing blocks. This can rise to upwards of 10% additional floor space in cases where random stone is used in very severe weather zones, which may require a 75mm clear cavity.

Diagram showing how wall width can be reduced with SureCav

Consistent clear cavity

Now guarantee clean and moisture free cavities with SureCav25! The SureCav25 cavity backing system is used to form a consistent 25mm clear cavity width in new masonry or timber frame constructed cavity walls of domestic and non domestic buildings and is fully BBA certified. It is our experience that a clear section of the cavity should always be present in the construction of the walls. The 25mm air gap between the outer layer of masonry and the insulation, coupled with the moisture beating design of the SureCav25 panels, will prevent any water penetration. The SureCav25 panels will also hold the insulation in place, adding to its effectiveness in preventing heat loss.

Diagram of Brick Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.

Experience the Future of Cavity Wall Construction!

Now drive down U-Values! SureCav25 allows for more room in the cavity for insulation, thus enhancing the thermal performance of the wall. Where heat conservation is the prime concern, by maintaining the original internal and external dimensions of the property, SureCav25 will release an additional 25mm in the cavity that can be used for extra insulation. 
  This example shows how a 100mm overall cavity width, comprising 75mm board insulation and a 25mm clear cavity using SureCav25, can achieve U-Values as low as 0.18 W/m²K. Alternatively, a 125mm overall cavity width, comprising 100mm board insulation and a 25mm clear cavity using SureCav25, can achieve U-Values as low as 0.15 W/m²K. (Figures calculated using Kingspan Kooltherm K108 Cavity Board insulation and the Kingspan U-Value calculator)

Chart showing insulation options for SureCav25

Protect from wind driven rain in all exposure zones!

In severe exposure zones there is often a requirement for a clear cavity up to 75mm, however, you can use SureCav25 and save up to 50mm space. In any exposed zone, SureCav25 protects the building envelope against water penetration. Good reasons to build with SureCav25!

  • BBA approval to form a 25mm clear cavity
  • Forms a barrier to protect from wind-driven rain
  • Excellent surface for the construction of any external wall masonry but shields the cavity and inner leaf from water ingress
  • Ideal for timber-frame and traditional block inner leaf, as well as SIPs, SFS and ICF construction

 

CAVITY WALL PROTECTION – BY DESIGN!

Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.

SureCav has many advantages over traditional systems

Available in 25mm or 50mm deep panels!

  • It saves money: SureCav effectively halves the cost of using a backing block support wall. 
  • It guarantees a completely clean cavity as no mortar can penetrate the polypropylene barrier, ensuring the wall-ties remain free from contamination
  • Injection moulded from 100% recycled polypropylene
  • It can result in extra internal floor area on a two storey house if the original external dimensions are used. 
  • SureCav is very light and takes up less than a quarter of the space of the concrete blocks it replaces
  • It is much more environmentally friendly, weight for weight, than concrete blocks that produce large amounts of CO2 in manufacture.
  • SureCav is easy to transport saving fuel (see below) and to move around a building site compared with concrete blocks.
  • Footings are 100mm narrower meaning there is less excavated material to dispose of and less concrete required in the foundations.
  • When installed, SureCav holds the insulation against the inner leaf, guaranteeing the insulation works to its full efficiency.
  • Using SureCav ensures no water penetration from wind driven rain with a 25mm or 50mm cavity not the usual 75mm demanded in some high exposure zones.

Natural stone is an outstanding building material

It is both practical and durable, and can be cut to any shape or form. The great thing about natural stone is that the older it gets, the more beautiful it becomes. Using natural stone shows that you take seriously your responsibility to care for your surroundings by actively striving to preserve, restore or improve the natural environment

Appreciation of the importance of flint

Flint and its effects can produce stunning results, especially when laid in alternate bands in stone or with brick quoins. 

The beauty of slate

Slate has been used as a natural building material for centuries. It is easy to shape and work with, making it a popular choice for wall construction. Slate is a long lasting material giving a beautiful effect, helping to promote your home as friendly to the environment.

Cotswold limestone block

Limestone is commonly used in the production of natural building stone and masonry products. One option is to use a random rubble effect using sawed limestone blocks with a recessed mortar joint, normally laid as a 110mm facing or outer leaf with cavity. Broken blocks or a Bookleaf effect is acheived by laying the blocks horizontally to create a layered ‘book leaf’ appearance. This is for facing or cladding only – not to be used as a structural wall – but an excellent example of where SureCav provides the best backing surface whilst maintaining a clean and moisture free cavity.

Testimonials

See how one contractor found using SureCav to protect from wind driven rain
Stone wall under construction with SureCav installed
If you haven’t used SureCav yet, look this product up – it’s the future!
JR Masonry
Brick traditional Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.
SureCav is a fantastic product and would use it on all jobs.
Ross Parkyn, Director, Duchy Brickworks
laying stonework easily against the SureCav system, SureCav 25. The Keeping a clear, dry, vented cavity free from any moisture. Eliminating water ingress issues and damp in homes . Used with stone and Brick masonry finish with SureCav25 bba approved cavity spacer rainscreen system keeping clear, dry, vented moisture and mortar-free cavities guarenteed whilst protecting against wind-driven rain and avoiding water ingress issues easily
Having used SureCav on at least 6 contracts we will never use backing blocks or shutter boards again.
Richard, EMM-LEC Ltd
Clear, dry, vented cavity creating using the SureCav 100% recycled plastic cavity spacer system
SureCav is a fantastic product and as we said in the CPD it has very much become a standard detail for stonework within the office. Perhaps now with knowledge of the further advantages of waterproofing and stability it may become more widely specified for other cavity wall types also. Many thanks for all your help and we hope that our support of your product will continue to push SureCav as a recognised standard for cavity wall construction within the industry.
Louisa Meek, CSA architects
standing infront of SureCav, 100% recycled cavity spacer rainscreen system, behind is insulation and traditional build in a partial fill cavity. The SureCav25 and 50 are both BBA approved for use in any exposure zone, offering protection against wind-driven rain and moisture issues.
We have used SureCav on a new stone house which was shortlisted for an RIBA Award. SureCav is a very good way, without the need for all of the additional foundations, and loss of floor space in the building associated with a blockwork backing to the external masonry. This saves time, space and money plus it gives the additional layer of weather protection provided by the SureCav sheets. We are currently using SureCav. We are very pleased with the high quality stonework. SureCav makes it easier to achieve the effect we want.
Phil Easton, Founding Director at Western Design Architects
Large house with red roof tiles
We have just built a new build using SureCav25 and found it superb to use, allowing us to increase insulation thicknesses within the build, enabling us to achieved a great EPC (energy performance) result. We also found it very easy to use as it guaranteed a clear cavity throughout the build and it also saved us using a backing block for the stone façade, actually increasing the internal rooms sizes by at least 200mm. Overall, we found the SureCav a fantastic system – thanks SureCav!
Tony Iles, Director, Tonic Construction Limited
Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.
My opinion is that SureCav is the way forward and is a great product and great solution. I can see this completely doing away with outdated backing block design. I have been personally really impressed with the overall SureCav system and have happily shown some of your prospective customers around. I talked to your prospective customers about the many benefits of SureCav, including it being simple and easy to erect and also, with the advantage on a tight site it taking up less valuable storage space and can be moved and handled with ease. The biggest advantage, of course, is that you can increase the overall floor area by using SureCav.
Daniel Cox, Site Agent
Builder laying bricks
One of the best products in the construction industry!
Dan, Greenhill Construction SW Ltd
Masonry construction complete using SureCav25, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.
I am so impressed with this product I would be happy for you to bring any of your prospective customers to my site at Wool, Dorset, and I will be pleased to show them your system.
Chris Allworthy, Barratt Homes Site Agent
House under construction with scaffolding around it
I really can’t recommend the SureCav product enough! Our self build project has been stressful to say the least with the rising costs of labour and materials, we’ve had to do whatever we can to save where we can. I thought a good way to do this would be installing the SureCav myself, however with never using the product before I was unsure of how straight forward this would be. I am happy to say it was an absolute breeze! The stonefacing looks great against it and the stone lads said it gave them a great flat structure to work against. This really is a 10/10 A*** product that we couldn’t be happier with and recommend enough.
Andy Holcroft, self-builder in Cumbria
Stone built home, under construction using the SureCav cavity spacer, rainscreen BBA approved system
The speed of build, easy storage and handling make SureCav an ideal system. We have found this especially to be the case where storage and working space on site is at a premium.
Ray Holmes, Hopkins Developments
Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.
Love this product, my local building control officer recommended it for my stone built project. The product was easy to install and made the building of the stone walls quick and easy. I’m now using it on all projects. Nice to see a product that does what it says!
Glen Davison
Masonry construction, against the SureCav BBA approved, cavity spacer, rainscreen system used with a partial fill insulation cavity.
I have specified Surecav on building regulations applications after the product had been recommended to me by the Local Authority Building Inspector and was interested to try it on my own extension. I found the product to be perfect for creating a random limestone facade which abuts the traditional rubble filled construction seamlessly yet overcomes the inherent problems of water ingress through the limestone fissures. Additionally, the reduction in depth of wall gives space for appropriate levels of insulation whilst achieving maximum internal space. I will continue to specify the product as the benefits far outweigh the costs and it is a breeze to install.
Jonathan Athay, JMA Design, North Yorkshire
Block wall under construction with SureCav in cavity
We have supplied the SureCav system for several years to bricklayers across the Southwest. Not only do we find the team at SureCav highly knowledgeable and helpful, but the SureCav system gets great reviews from all our customers who install it. Customers who use SureCav will continue to use it on future projects as it is a quick, easy and professional system to instal. The service is second to none and I really can’t find a fault. Suitable for both timber frame and masonry, it really is a fantastic system.
Eric Sutherland, Branch manager

Multiple Benefits
of Using SureCav

Using Surecav provides multiple benefits

With the June 2022 building regulations now in force, with SureCav25 and 75mm insulation, you will not need to amend your drawings to achieve 0.18Wm2K in an overall 100mm cavity.

Keep the wall width to a minimum and avoid having to purchase more expensive lintels. A new and lightweight alternative to heavy and expensive concrete backing blocks.

SureCav increases floor space and acts as a rainscreen to the harshest weather. BBA certified and readily available to specifiers, SureCav is the ultimate space and cost saving solution for cavity wall construction.

Read more

Surecav
Product Range

SureCav 50 cavity spacer rainscreen system
SureCav 50

The 50mm cavity spacer system. Creates a guaranteed clear, dry, moisture and mortar free BBA approved 50mm residual cavity
Panel size: 1200mm x 450mm x 50mm

£150.00 ex VAT

SureCav 25. The Keeping a clear, dry, vented cavity free from any moisture. Eliminating water ingress issues and damp in homes . Used with stone and Brick masonry finish with SureCav25 bba approved cavity spacer rainscreen system keeping clear, dry, vented moisture and mortar-free cavities guarenteed whilst protecting against wind-driven rain and avoiding water ingress issues easily
SureCav 25

The 25mm cavity spacer system. Creates a guaranteed clear, dry, moisture and mortar free BBA approved, 25mm residual cavity 
Panel size: 1200mm x 450mm x 25mm

£150.00 ex VAT

Surecav washers
Washers

Washers are used when installing SureCav on timber/SIP frame buildings to create a watertight seal. 5 per panel recommended
Size: 6mm diameter hole x 10mm deep

£11.00 ex VAT

Surecav type W vent
Type-W Vent

Achieves 1500mm2 per linear meter
BBA ventilation requirement, when installed every 0.5m high and low with these vents
Size: 105/115mm x 65 x 10mm

£24.00 ex VAT

Surecav type W vent-extender
Type-W Vent Extender Duct

The extension ducts are used with
the Type W vents. The Extenders are required with an outer leaf over 100mm deep.
Size: 200/225 x 65 x 10mm

£49.00 ex VAT

Certifications

View all certifications
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BBA Approved

BBA Certification is a trusted mark of quality in construction, awarded after rigorous testing by the British Board of Agrément. It ensures products meet all relevant standards and are fit for purpose.

LABC Approved

Local authority building control teams help people comply with the latest building regulations by giving feedback on plans and providing site inspections.

NBS Source

Used by architects, specifiers, and construction professionals, providing easy access to high-quality building product data. Offering detailed product information, technical specifications, and compliance documentation, all in one place

Talk to an expert about using SureCav for your next project

Call us now on 01963 34660 8am – 5pm (Mon-Fri), or fill in the contact form, to find out how SureCav benefits your build or ask us a question!

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  • Fully Accredited by BBA
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