Fast-Track Your CLAYBOARD VOID FORMER Heave Protection
Fast-Track Your CLAYBOARD VOID FORMER
Clayboard, or Ground Heave Collapsible Void Former, is a sustainable construction product which allows concrete slabs to be up to 30% thinner than other void formers on the market. It also significantly reduces soil excavation, muck-away and delivery costs. It is ideal for concrete heave protection and foundations where the core shrinks in the wet period.
Preparation
Whether you are building new homes, extension to existing structures or a commercial project you need to protect your foundations from clay heave. Shrinkable clays, which contain a high proportion of mineral particles of less than 0.002mm in diameter, cause foundations to expand and contract under wet and dry conditions. This movement is known as heave, which is not only damaging to foundations but can also cause the structure above to move or collapse.
To prevent this from happening, void formers are used to create a space where soil can shrink and expand without exerting pressure on the concrete slab or beam above it. Void formers are made from materials that can collapse to form a space, called the void dimension, into which the soil can swell.
Clayboard is an environmentally friendly void former that is used beneath concrete slabs to accommodate clay expansion. It is also used on the sides of beams where heave is a problem.
It is made up of a biodegradable honeycomb core set between lightweight polypropylene facings, and when it is dry the board is strong enough to support the weight of the concrete and steel reinforcement that has been added. Once the concrete is poured and set water is introduced to the board using the voidpak system which softens the core and makes it collapse leaving a space to accommodate clay expansion without exerting pressure on the structure above.
After the void has formed, the top and bottom facings of the board should be stricken so that excess water drains away from it and all pipes are sealed with some waterproof sealant or cement. This way the material is able to withstand the load of wet concrete up to 1m in thickness.
Installation of Clayboard void former is relatively easy, however it should be kept in a dry condition before installing it on the foundation. Moreover, it should be placed face up on the ground, and covered with at least 500g of polythene sheeting, overlapping and taping all the joints.
Installation
Fast-Track Your CLAYBOARD VOID FORMER HEAVE PROTECTION
Clayboard is a highly effective void former that is specifically designed to accommodate the expansion of clay without exerting pressure on the foundation below. It is often used under concrete slabs and also on the sides of beams where clay heave is a problem.
It consists of a biodegradable honeycomb core set between lightweight polypropylene facings that have up to 70% recycled content. The biodegradable material is an environmentally friendly option that makes it a great choice for the green conscious building designer.
The best part is that it is easy to install. Unlike other void formers, Clayboard can be set directly into the ground, without the need for expensive scaffolding.
However, it is important to note that Clayboard does require some maintenance to ensure that it remains effective. This includes a periodic inspection of the product for signs of wear and tear, as well as occasional cleaning to remove dirt or debris.
As with all products that claim to be the best void former, it is always a good idea to read the manufacturers literature carefully before purchasing and installing. This will ensure that you get the most out of your heave protection solution and avoid any costly mistakes. There are many different heave protectors on the market so you need to choose one that is right for your project.
Maintenance
CLAYBOARD VOID FORMER HEAVE PROTECTION
The use of clay void formers or compressible materials is recommended to absorb the movement of soil or ground water caused by clay heave in a range of commercial and domestic construction projects. They are designed to be used underneath concrete slabs, beams and floors to accommodate render carrier boards the expansion or shrinkage of clay without exerting pressure under the structure. These void formers are made up of an organic or biodegradable honeycomb core covered with lightweight polypropylene facings and offer an environmentally friendly solution to ground movement problems caused by clay heave.
To prepare the foundation for a Clayboard void former, it is advisable to dry out the site and add sand binding before installation. The board should also be covered with 500g polythene sheeting before it is laid on site. It is essential to keep the board dry at all times while it is on the site, as rain can cause it to degrade if not kept in a dry environment. It is a good idea to have a sump and pump arrangement installed to drain away excess water should it occur. Once the void former is ready for installation, some water should be added to the board, so that it reaches the honeycomb core.
