Posted By ivorfire Hi, The spiral staircase should comply with Approved Document K (if found acceptable for use). The cost in comparison will probably be a little cheaper, along with some saving on space, in comparison with traditional stairs. However, there are other issues to considered, (as always). You dont give a reason for the change? Spirals stairs can be used if there are no members of the public and limited in terms of employee numbers. However, with DDA the design of the spiral may affect the use by any disabled persons (employees) therefore Approved Document M should be considered. (This being for access and use only). This being from a walking point/impaired sight of view and the sizes of treads and risers taken account of where there is no lift. Under Approved doc part M it is unlikely that most forms of spirals will be acceptable. This is unless that the larger types are used which now puts costs up, and generally that as the size of treads and risers vary so much with spirals, [on the same step], which is the characteristic that makes them difficult for use. If the existing arrangement (straight stairs) has a means of escape within a short distance (at lower level) i.e. 3 metres this would have been acceptable in the past. On replacing the stairs the travel distance may be increased and therefore may no longer be acceptable,i.e. the provision of the spiral stair. Any stairs being replaced would be considered under Approved Document B (Fire Safety) both as current position (new stairs) and for means of escape purposes for the floor they serve. The overall arrangement would be needed to be considered and not just the point of replacement of stairs, i.e. the means of escape provision from the floor level (Control Room) they serve. To get further information you would be advised to contact your Local Authority Building Control Office and seek some general advice. This should be freely available and their interpretation of the documents would give you your bench mark for your area. If it is likely that changes are to be made and if the premises has a fire certificate you would need to consult your local fire safety office as the means of escape factors are changing, under the terms of your fire certificate. As a place of work, [Fire Preautions workplace Rgulations 1997 (as amended) applies] and this area / change would need to accounted for within the fire risk assessment, and emergency action / evacuation plan and duly notified to employees. Hope this helps.

Posted By ivorfire The Approved Documents are those that Building Control bodies use for the application of building regulations. The following website information should assist. http://www.odpm.gov.uk/s...ge/odpm_breg_600157.hcsp http://www.odpm.gov.uk/s...dpm_index.hcst?n=240&l=2

Posted By Andy Lightbody Another point to remember on a practical basis is to ensure that access is still available for getting furniture, computers etc into and out of the control room. There have been various cases where spiral staircases have been installed only with expensive alterations required subsequently for the above.