Frequently Asked Questions

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Q. What building interface considerations are there?
A. The raised access floor will possibly interface with the following elements which will require consideration at the design phase:

• Underfloor services
• Thresholds at doorways/lift lobbies, etc
• Cladding/curtain walling
• Perimeter heating
• Skirting
• Partitioning built off or through the raised floor
• Changes in level e.g. ramps or steps.

Q. How level will the installed raised access floor be?
A. The raised access floor will be installed level within the parameters of the Access Flooring Association Code of Practice which requires +/- 1.5 mm over any 5 metre square and +/- 6 mm over any basic space. This is in line with the requirements of the PSA MOB PF2 PS/SPU specification.

Q. Will the raised access floor require to be electrically earthed and how is this achieved?
A. In most cases due to steel used in its construction the raised access floor will require to be earthed in line with local conditions (UK, 16th Edition I.E.E. Wiring Regulations)

Q. What happens to the floor panels at perimeters?
A. At perimeters the floor panels are cut to fit on site by the use of a bandsaw. The exposed chipboard core will be protected by adhesive backed aluminium foil tape applied to the cut panel edge. The cut panel will be cut to allow for a 10mm expansion gap at all abutments. This gap will normally be filled with a class”0” resilient closed cell foam tape adhered to the cut panel edge. The cut panels will not be cut less than 150mm wide otherwise they become impractical to adequately support.

The perimeter pedestals will be fitted with perimeter caps that are specifically designed to hold the perimeter cut panels in place laterally. Gravity lay perimeter cut panels will be mechanically fixed to the pedestals to provide additional stability. The cut edge of perimeter panels will normally be supported by the use of perimeter stringers or additional pedestals. As a matter of course all cut edges at door thresholds etc will have additional support by the use of perimeter stringers or pedestals.

Q. Is the concrete sub floor sealed prior to the raised floor installation?
A. Under normal circumstances the concrete sub floor will be sealed by the application of 2 coats of a coloured PVA dust sealer. These two coats may be of the same colour or different colours to signify complete coverage. This will prevent dusting of the sub floor during use and help prevent dust ingress into service runs etc. The PVA sealer is compatible with the epoxy resin pedestal adhesive.

There are occasions when the concrete sub floor will be sealed with 2 coats of a epoxy resin coating in order to provide a surface that will withstand a lot of traffic during the installation period and provide a totally dust free void. These are normally large and specialised computer/data processing type environments.

Q. How to avoid problems associated with raised access floors?
A. As the raised access floor performs a critical function within the working office environment faults with the system can cause problems from simple annoyance through to major disruption. Many faults are rectifiable to a varying degree, however it is essential to consider the following key factors to prevent such occurrences;

Causes:

• Use of inappropriate products and/or solutions
• Use of inappropriate class or grade of raised access floor
• Poor quality products and/or installation
• Raised access floor not lifted and replaced in accordance with manufacturer’s instructions
• Lack of appropriate maintenance.

Effects:-

• Movement, rocking and squeaking of floor panels
• Difficulty in removing and replacing panels
• The floor may require modification in order to perform satisfactorily
• Areas of floor or the complete floor may require replacement
• Possible floor collapse with likely damage and injury.

In order to avoid the problems outlined it is important that the raised access floor be correctly specified at the outset. This specification should include not only the product requirements but also the installation requirements. Once installed the raised floor must be maintained correctly in line with the manufacturer’s instructions.