Paving Sand Stabilising - FAQS - Online Shop
Paving ‘Jointing Sand Stabilisers’ are not normally the same thing as a “Paving Sealer” , as sand stabilisers are more specifically designed to penetrate into the loose graded sand used to fill the joints, and bind the sand grains together between the blocks in the ‘flexibly’ laid pavement, i.e. bedded in compacted sand and fill. The so-called ‘stabilised’ sand then greatly reduces weed growth and the sand grains being eroded by weathering. Where necessary, higher performance, specialist applied jointing sand stabilisers can be used to completely seal paved surfaces and resist sand loss in commercial areas e.g. by Mechanical Street Cleaning machines, including vacuum sweeping and power washing operations, such as on airfields and military bases, though these are specialist products that must be applied by specialist contractors.
Paving Jointing Sand Stabilisers in the sider context, are generally used for areas such as supermarket car parks and arouns retail and commercial development.
Here the main function is to stabilise graded sand tamped or wacked into the block paving joints, which should be a maximum of 5mm wide, excluding any chamfered arrises (note- these chamfered sections must never be filled with sand).
Important note: Paving jointing sand stabilisers are not normally used with rigid paving such as for patios and driveways or streetworks using concrete or natural stone pavers, as these require a paving jointing mortar to be used as the final grout between the different elements, especially where the joints in small format paving are designed to have a nominal width of at least 10mm, which will also vary due to the profiles of the stone. Here a pre-batched GftK Paving Jointing Mortar should be selected according to the stone paving area’s use, exposure and requirements.
Paving Sealing products must be extremely low viscosity in order to ensure penetration of the surface and avoid delamination or peeling-off, and then to provide a sealed waterproof, or water-repellent and frost-resistant surface. The ‘surface coating’ types must also harden to a dense film that can increase the abrasion and wear resistance, plus they can possibly also improve the appearance of the surface. Paving Sealing products will have a very limited effect on the reduction of weed growth in the joints.
‘Paving Jointing Sand Stabilisers’ versus ‘Paving Surface Sealers’
Paving Jointing Sand Stabilising products have different design and formulation criteria. These need to be less penetrative but ‘tough and cohesive’ as well as more ‘flexible and elastic’ than the Paving Sealers, in order to adequately bind the sand particles together and keep them together in the joints, whilst also accommodating the natural flexing and movement of flexibly laid block pavements. The potential for weed growth is also considerably reduced as the flexible material tends to prevent seeds entering the joints and successfully germinating.
In summary – Always use a purpose designed and correctly formulated paving jointing sand stabilising product such as GftK’s ‘vdw 870’ for domestic applications. This is an acrylic resin based, water dispersed easy to use and safe jointing sand stabiliser. For more onerous conditions requiring even higher performance, such as high traffic commercial applications, the use of Resiblock 22 can be considered. This is a far more expensive and controlled application with severe site limitations and sanctions for use, because this product is based on aromatic polyurethane resin with isocyanate content and it is solvent dispersed.
These paving jointing sand stabilisers will both bind and anchor the sand in place, plus they will also provide a protective coating on the surface of the blocks to some extent; whereas paving sealing impregnations and surface coating sealers will effectively seal the surfaces, but will have no significant or durable effect on binding and stabilising the sand in the joints.
Jointing Sand Stabilisers for Sand Filled Joints in Block Paving
In principle all sand filled joints in block paving that are to be stabilised must be a maximum width of 5mm (normally nominal 1 – 5mm), with a minimum sand depth of 10mm, excluding any chamfered edges, as all sand from within any chamfered areas must be completely removed before applying the jointing sand stabiliser.
Paving Jointing Sand Stabilisers such as GftK’s ‘vdw 870’ will both bind the sand grains together and also to the edges of the concrete blocks, which helps to anchor the sand and the paving in place, plus this higher performance, purpose designed jointing sand stabilising products, will also significantly reduce any future weed growth etc.
GftK’s vdw 870 can provide a very useful and cost-effective, easy to use, water dispersed and environmentally friendly solution for domestic applications, such as on patios and pathways and driveways with light vehicles (normal domestic cars and bikes etc.).
It is available to buy direct from our Online shop.
GftK Sand Stabilising Solution Products
GftK vdw VarioSand GftK vdw 870For commercial applications with high performance requirements, these should always be undertaken by trained and experienced specialists that understand the important application requirements and related environmental considerations. We can provide detailed advice for your project, including the names of specialists in your area of the UK from our national network of professional paving and landscaping contractors.
You can call 01257 266 696 for FREE expert advice and assistance on your paving jointing sand stabilising project, or email us at technical@nccstreetscape.co.uk