FLOORING contractors who undertake installations in office environments will likely be familiar with working over raised access floor panels. Typically made of metal or cementitious material and supported by adjustable vertical pedestals, these panels create a hidden void for the routing of cables, wires and piping. Access to services can be achieved easily by removing individual panels.
Historically, raised access flooring would be found mostly in larger workplaces, including government offices and call centres with significant telecoms and IT requirements. Nowadays, they’re equally as common in many open plan office environments, enabling IT and electrical services to discreetly reach workspaces spread across a floor.
While their benefits in these environments have made them increasingly popular, raised access panels require a few special considerations when it comes to preparations to make them ready to receive floorcoverings.
When applying a levelling compound directly over the top of installed raised access flooring, the product will sink into the gaps between individual panels. This can potentially result in weak points which can cause the levelling compound to crack and lose its integrity, possibly leading to floor failure. Therefore, the gaps must be filled before a levelling compound is applied and floorcoverings are installed to ensure the performance of the installation throughout its lifetime.
Additionally, it will be important to prime the subfloor prior to the application of other flooring preparation products. When used over non-absorbent subfloors, such as metal panels, priming serves to promote the application characteristics of subsequently applied levelling compounds. When used over absorbent subfloors, such as panels made of cementitious materials, priming also serves to promote adhesion, as well as stopping the unacceptably rapid drying of levelling compounds.
Says F Ball & Co: ‘To save valuable time and expense for the contractor, cement-based primers, such as F Ball & Co’s Stopgap Fill and Prime, are available that are designed specifically for use over raised access panels and fill the gaps at the joints between the panels whilst priming the subfloor. Stopgap Fill and Prime is a two-component, fast drying flexible cement-based primer that is suitable for use over raised access panels.
‘The product has a thixotropic consistency, meaning it flows freely but sets to a gel-like consistency on standing, enabling the joints at panels to remain filled and preventing depressions resulting from a subsequently applied levelling compound sinking into them while setting. Once cured, the flexible nature of the product will accommodate any movement in the substrate.’
The company continues: ‘Applied up to a thickness of 1mm, Stopgap Fill and Prime sets rapidly and is ready to receive foot traffic in as little as 60 minutes, meaning the application of subsequent products can commence swiftly. Stopgap Fill and Prime offers exceptional adhesion to a wide range of other subfloor types including substrates with well-bonded, waterproof residues of adhesives.’
For best results, a flexible levelling compound, such as F Ball’s Stopgap 700 Superflex, should be applied once the primer has cured, the company says. ‘These products contain tiny fibres that help deal with movement that flexible subfloors are prone to, preventing cracks and maintaining the levelling compound’s integrity.’