Access floors play a number of different roles in today’s increasingly high tech environment and it is important to identify the proposed function of your installation. A key point is that a floor void in a busy comms area will need to be accessed almost daily while a floor in a general office area will only need to be lifted occasionally. Please have a look at the various products we offer to identify the best solution for each area of your project.

2. How high should my floor be?

As with the previous question this really depends on the use you plan for your floor but it is often our experience that an extra few millimetres at design stage will save a load of problems later. A common mistake is not to make enough allowance for tolerances in the construction of the sub-floor especially with concrete planks, which are cambered.

We can install flooring systems down to a minimum of 60mm overall for refurbishment projects – however this reduces the usable void to 30mm, which will restrict potential use.

If space permits we would recommend a minimum design void of 100mm to accommodate power and data increasing to 150mm if you plan to include pipe-work for radiators.

Comms and data areas should be slightly higher – there are always extra services required at some later stage and the extra void enables cabling to be turned up into cabinets more smoothly.

Large comms rooms may need to have a 600mm void or even higher to accommodate underfloor air conditioning – we have done at least one installation that I could walk under without bending down!

3. What do you do if the existing floor isn’t level?

All the systems that we supply are fully adjustable within their designated ranges.
CAF 600 concrete pedestals are supplied in 5mm increments from 25mm to 210mm with fine adjustment shims between each size – an accurate pre-installation laser level survey identifies the quantity of each size required.

The various types of steel pedestal each have a designated range and again a level survey identifies the contract requirements.

Using either type of under-structure the installation of an access floor can convert your uneven sub-floor to a flat and level working platform for following trades.

4. Can I put an access floor on to an existing wood floor/ vinyl tiles/ concrete planks / a block and beam floor?

We have done plenty of installations on plywood, chipboard and other wooden sub-floors provided these are reasonably level – if in doubt get us to have a look.
As our under-structure needs to be bonded with an adhesive, which sticks well to concrete, wood, or steel we usually recommend that vinyl or lino floor coverings be removed prior to installation.

Concrete planks should not be a problem provided that the manufacturer of the planks is made aware that a raised floor is to be installed on them and prepares the surface accordingly.

We have also done several installations directly on to beam and block floors but always recommend that you check the point load specifications with the relevant beam and block manufacturer.

5. Where does the access floor come in a build programme?

There are different schools of thought on this one. Access flooring should ideally not be considered until the building is watertight and plastering and other wet trades completed.

As regards co-ordinating underfloor services we would usually expect to see heating pipe-work installed prior to the access floor. Electrical services and data cabling are a slightly different issue – these are often quite fragile and can be damaged if not protected by the floor. A good compromise is to install containment just before our works with panels then being lifted to fit the more fragile components. We will always be happy to help with the co-ordination of the works.
Suspended ceilings are just before or just after us and skirtings need to follow behind.

6. Is raised floor just for offices?

No - all kinds of premises have access floors nowadays. We have just finished a 4000m2 installation in a college block with all the services in the floor eliminating the need for a suspended ceiling. Schools, shops, police stations, fitness centres, hospitals, production facilities and museums all number among our previous installations.

7. What do I do about partitions?

We are often asked if our raised floors will support partitions or whether they need to be built off the sub-floor – the answer is that office partitioning usually increases floor loading by no more than 1kN per m2 which can easily be carried by any of our systems. This in turn will make the routing of services in the underfloor void much simpler and means that office re-configuration at a later stage will not leave holes in the raised floor.

8. What size carpet tiles should I use?

If you are installing carpet tiles in a general office area it is usual to use the standard (and usually cheaper) 500 x 500mm tiles to the access floor. Lifting the floor does mean lifting two rows of carpet tiles for each row of access panels but provided the carpet has been correctly fixed with tackifier adhesive this is not a difficult task!

It is usually a mistake to use loose carpet tiles in a comms room – we really prefer a bonded vinyl finish as this is more hard wearing and much easier to clean but factory bonded 600 x 600mm static conductive carpet tiles are also an option.

9. Can I fit a raised floor myself if you sell me the bits?

We are happy to supply components for repair and replacement of any type of raised floor.
We do not sell the CAF600 concrete pedestal system on a supply only basis but will happily help you out with any steel pedestal floor if you want to do it yourself – free advice available!

10. What are the PSA standards for raised access floors all about?

The MOB PS/PSU specification was introduced in 1982 by the now defunct Property Services Agency in response to problems that occurred in the early days of access flooring and has helped considerably to make installations in the UK probably the best in the world.

The use of access flooring has changed vastly since the standard was written (or last modified in 1992) and it is fair to say that a fair amount of it is not really relevant to ordinary office use rather than the main frame computer rooms which brought about the birth of raised floors.

The requirements of the PSA standard have however resulted in the use of steel encased panels rather than the edge banded panels with steel stuck to the top and bottom more widely used in Europe. The experience of our Special Works Dept in reinstating old floors has given us a strong preference for fully encased panels due to their long term performance.