BS 5440-1:1990

Foreword
Committees responsible
Specification
1 Scope
2 Definitions
3 Preliminary design considerations
3.1 Types of flue system
3.2 Flue termination
3.3 Fire precautions
4 Individual open flue: natural draught
4.1 Design
4.2 Installation
4.3 Commissioning
5 Individual open flue: fanned draught
5.1 Design
5.2 Installation
5.3 Commissioning
6 Shared open flue: natural draught
6.1 Design
6.2 Installation
7 Balanced flue: natural draught
7.1 General
7.2 Installation
7.3 Post installation check
8 Balanced flue: fanned draught
8.1 General
8.2 Installation
8.3 Post installation check
9 Shared room-sealed: natural draught
9.1 Design
9.2 Sizing
9.3 Terminal design and location
9.4 Inspection
9.5 Appliance selection and installation
9.6 Commissioning
10 Special categories of flue system
10.1 Flue systems for use with condensing appliances
10.2 Closed flue systems
10.3 Balanced compartment
10.4 Shared open flue fanned draught systems
10.5 Other categories of flue system
Appendices
A Calculation method for flue sizing
B Flue terminal positions
C Balanced flue installation in properties of timber
      framed construction
Tables
1 Location of roof mounted terminals for individual
      natural draught open flue systems (minimum height
      of base of terminal)
2 Condensate-free lengths of individual open flue
      used with a gas fire
3 Appliance/chimney combinations which require the
      chimney to be lined
4 Voids below appliance connections
5 Minimum flow rates for fanned flues
6 Appliances discharging by way of subsidiary flues
      into a main flue
7 Normal Se-duct block sizes
8 Se-duct sizes for continuously burning appliances
      in flats
9 Se-duct sizes for combinations of instantaneous
      water heaters (30 kW input rating) and
      continuously burning appliances in flats
10 Balanced compartment air inlet duct sizing
11 Resistance factors for use in calculating
      equivalent heights
12 Inlet and outlet resistances
13 Minimum equivalent heights needed
14 Minimum dimensions of flue terminal positions (all
      types)
Figures
1 Flue systems
2 Flat roof, with parapet
3 Flat roof, envelope method
4 Flat roof, where the flue outlet is more than 10
      heights (h) away from all structures
5 Flat roof, with flue close to parapet
6 Flat roof, with no parapet
7 Flat roof, with structure close to flue outlet
8 Pitched roof, not greater than 45 degrees
9 Pitched roof, within 1.5 m of a structure on roof
10 Pitched roof, exceeding 45 degrees
11 Pitch roof, internal route, pitch not exceeding
      45 degrees and ridge termination
12 Pitch roof, chimney within 1.5 m from dormer
      window measured horizontally
13 Maximum lengths for condensate-free flues for
      appliances other than gas fires
14 Connections to existing brick chimney
15 Typical methods of sealing flue liner
16 Sealing of false chimney areas
17 Shared flue systems and flue block types
18 Shielding of plastics gutters
19 Shared room-sealed systems
20 Balanced compartment installation
21 Worked example 1
22 Worked example 2
23 Flue terminal positions
24 Circular balanced flue fitted to timber framed
      structure
25 Rectangular balanced flue fitted to timber framed
      structure