Checklist: Doors

1. Location and environment
These are fundamental factors and will determine requirements for durability and security, which in turn will influence selection of material. For example, requirements for an external door in a wet or corrosive situation, such as a coastal or industrial location, will differ significantly from those for an internal door in a dry environment.

2. Material
The specifier should consider the following when selecting a material:

• Durability: Metal doors must be protected against corrosion; timber doors against fungal and insect attack.
  
• Strength: Carefully selected, a door will safeguard the occupants and contents of a building against theft and vandalism. In some buildings, terrorist attack should also be considered, and the probable method of attack must be assessed.
  
• Environmental impact: This can be reduced by selecting materials with low embodied energy from sustainable sources.
  
• Cost: Likely maintenance and replacement costs must be added to the capital outlay.

3. Weather resistance
Until recently, weather resistance of doors was assessed using British Standards relating to windows (BS 5368-1 to –3). These have been replaced by harmonised European Standards for both windows and doors. Characteristics covered include air permeability (BS EN 12207, see also BS EN 12426 for industrial, commercial and garage doors), watertightness (BS EN 12208) and wind resistance (BS EN 12210). A complementary British Standard, BS 6375-1 Performance of windows and doors. Classification for weathertightness (including guidance on selection and specification) is in preparation. Air leakage is also covered in Part L of the Building Regulations.

4. Security
To ensure the security of the door, consult the following documents:

• LPCB Standard LPS 1175 specification for testing and classifying the burglary resistance of building components, strongpoints and security enclosures.

  This contains a rationalised version of the burglar-resistance classification system specified in DD ENV 1627.
  

• Product Assessment Specification PAS 24-1. This provides a similar method for testing and assessing the enhanced security performance requirements of single-leaf external door assemblies to dwellings.

  Both documents feature in a checklist of standards relevant to security published by Secured by Design, a police initiative supporting the principles of designing out crime. The SBD website (www.securedbydesign.com) offers useful design guides, including a doors and windows security guide.

5. Fire resistance
Fire-resisting doors are required to perform two main functions:

• To protect escape routes from the effects of fire, enabling building occupants to reach final exits
  
• To protect building contents by limiting the spread of fire and smoke, while still allowing the passage of people or goods from one compartment to another.

The recommendations in BS 5588 reflect the current approach to specifying fire resistance of doors. Both the code and Building Regulations set performance levels for integrity of doors when tested to BS 476-22. However, following the publication of harmonised European Standards, most future testing will be done to:

• BS EN 1634-1 for fire doors and shutters
  
• BS EN 1634-3 for smoke control doors.

A transition period is proposed, during which time products can be tested either to BS 476 or to the relevant part of BS EN 1634.

The draft European Supplement (ES) to Part B of the Building Regulations requires all fire doors to be classified in accordance with BS EN 13501-2, which is not yet published. The Scottish Building Regulations Technical Standards make reference to the new test standards and to a draft version of the supporting standard prEN 13501-2.

Documentary evidence of fire-resisting doorset performance can be obtained from door manufacturers in the form of fire test reports, product conformity certificates or assessment reports. These should state clearly the maximum fire resistance performance for each complete door assembly.

6. Thermal performance
To satisfy the elemental method described in the Building Regulations Part L1 (dwellings) doors must achieve specified U-values. Unfortunately the wording for the requirements is not particularly clear. Table 1 has two references to doors – linked to glazing in metal frames (U-value 2.2 W/m2K) and glazing in wood or PVC frames (2 W/m2K). However, table A1 requires a U-value of 3.0 W/m2K for solid wood doors. Metal doors are not mentioned. References to doors in Part L2 (non-dwellings) relate only to air leakage.

The government has asked BRE to operate a website (http://projects.bre.co.uk/partlfaq) as a means of delivering answers to queries that are being raised.

7. Access for the disabled
The Disability Discrimination Act 1995 couches requirements for doors in general terms, such as under "means of access". Building Regulations Part M gives separate requirements for dwellings and other buildings.

For guidance on the design of buildings and their approaches to meet the needs of disabled people, see BS 8300. Topics include provision of self-closing doors to principal entrances, effective clear width through doorways and door furniture.