DOORS: ACCESS ALL AREAS
The implementation of proper access to all buildings is thanks to Approved Document M of the Building Regulations' Access To and Use of Buildings' supplemented by 2004's BS8300: Design of Buildings and their Approaches to Meet the Needs of Disabled People, Code of Practice.
A major change is the requirement for a clear opening width of 800mm for new public buildings (from an access route at least 1,500mm wide), 825mm where the opening is at right angles to an access route 1,200mm wide, or 1,000mm in the case of external doors to buildings used by the general public.
This clear opening is measured up to any projecting door furniture (if the door is restricted to 90° or less) or weather barriers etc, making it a significantly enhanced standard.
A stark contrast Entrance doors must also be signposted clearly and recognised easily in the overall scheme, making considerable architectural demands in terms of visual contrast. This was referred to originally as a light-reflectance value of more than 30 points, with BS8300 referring specifically to differences of colour and luminance.
These regulations are at once extremely specific and open to interpretation; the end result could easily be seen as an enforced Noddy aesthetic of garishly coloured doors.
In fact, the rules have now been amended to 20 points as a minimum, because the original figures were based on what seems to have been only spurious evidence.
Formica has been experimenting with young artists and designers to create a series of visually arresting decorative laminates, which would certainly make doors extremely visible. Similarly, C/S Group has developed wood-effect acrylic vinyl for demanding environments such as healthcare and education buildings.
There have been lingering doubts about the viability of stainless-steel ironmongery in terms of contrast, but these seem to have been dispelled by the revision down to 20 points. There is also a requirement that, where doors are being held open, the leading edge of the door must contrast with the surface of the door leaf. The most elegant way to achieve this is by using a contrasting PVC sleeve on the intumescent strip. For internal doors, the regulations require the door frame to contrast with the walls, bringing decorative schemes far further back into the design process to demonstrate compliance.
Sounds about right After accessibility, the other major area to come under increased scrutiny is sound insulation. Approved Document E gives minimum acoustic performances for doors in new buildings. For 'Rooms for Residential Purposes' (RRPs), in hotels, for example, this minimum is 29dB Rw.
With a standard residential FD30 door weighing around 20kg, this standard cannot be achieved: even bulking up the door, either by improved construction or increased weight, will not bring the required effects, as most sound is transmitted not through the door leaf but through the gaps around its edges. LS Group has developed high-technology cores that absorb sound that might otherwise be transmitted by the vibration of a dense, yet rigid, core, for its brand LS Leaderflush Shapland.
Despite these developments, the rise of the combined fire, smoke and acoustic seal system (also incorporating the threshold) appears inevitable. Although the document refers to its inclusion 'where practical', the door can only achieve the grade where seals to the bottom of the assembly are included.
Lorient's DS combined fire, smoke and acoustic seal, for instance, avoids interruption from non-projecting ironmongery to achieve maximum acoustic insulation.
For schools, where £6.3 billion is abouts to be invested in a huge programme of refurbishment and rebuilding until 200708, the new rules are even more exacting.
BB94 demands that all doors exhibit 30dB Rw of sound reduction, and 35dB Rw in the case of music rooms. Ize is developing a sector-specific education ironmongery suite in conjunction with BDP, which has a stainlesssteel handle designed to meet the rigorous physical demands of a school environment.
Also incorporated is Kaba's classroom cylinder, on which the internal thumb turn can be used to unlock, but not lock, the door.
Using the force The final piece of legislation that will affect doors concerns maximum opening forces.
The subject impinges more on ironmongery than on door design, but is still likely to be a pivotal issue in the development of opening design. Approved Document M specified a maximum opening force for doors of 20N.
This was extremely onerous and provided an insufficient closing force to hold the door shut against the pressure differentials occurring in a fire.
It has subsequently been amended to allow for a maximum opening force of 30N when measured at 0-30°. Jebron's Dual Power electromagnetic hold-open door closer provides an elegant solution, using a light spring to open the door and a second, more powerful, spring to close it in a fire situation.
Sustainable sources The other major concern for specifiers is sustainability. The world of third-party accreditation is complex and crowded. The government established the Central Point of Expertise in Timber (CPET), to provide information and advice and support its timber-procurement policy.
Last year's guidance note differentiates between timber sourced legally - verifiable proof of which is now a minimum condition of government contracts - and sustainably.
Offers meeting the variant specification for sustainability are being given priority over tenders that meet only the minimum legal requirements. A number of bodies certify timber independently, the best known of which is the Forestry Stewardship Council (FSC). Others include the Canadian Standards Association (CSA), the Programme for Endorsement of Forest Certification, the North American Sustainable Forestry Initiative and the Malaysian Timber Certification Council.
The CPET found that all five of these schemes could deliver UK government requirements for legality, and that the CSA and FSC schemes could satisfy sustainability requirements without any further documentation. The FSC is currently the only scheme recommended by Friends of the Earth.
The industry is likely to move towards the systems employed on the continent, particularly in Germany and central Europe.
There, door manufacturers supply a total package, including locks, ironmongery and integral blind systems. LS Group is beginning to do something similar in this country, using products such as its own Careview blind system and collaborations with various ironmongery manufacturers.
The Access for Health Initiative, led by architectural ironmonger Yannedis, is also talking the industry in a similar direction.
Likewise, Arrow Industrial, with its Arrowplas GRP pre-hung doorsets, provides a total package for the service end of health infrastructure. The other significant move is likely to be towards an increase in automatic door closers to help satisfy the new regulations for ease of opening and access. Kaba and Geze are among the companies developing sophisticated access management integrated into building-control systems.
Finally architects are beginning to come around to the idea of designing complete doorsets, with Anshen Dyer and dRMM building on their experiences at Great Ormond Street and Kingsdale School respectively by looking at further possibilities aimed at the health and education sectors.