Locations of flue outlets serving gas appliances

Table 4.3 Locations of flue outlets serving gas appliances Distance Location: Minimum separation distances for terminals (mm) A Below an opening(1) Balanced flue - Natural draught: 0–7 kW: 300; >7–14 kW: 600; >14 to 32 kW: 1500; >32 kW: 2000 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 300 B Above an opening(1) Balanced flue - Natural draught: 0–32 kW: 300; >32 kW: 600 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 300 C Horizontally to an opening(1) Balanced flue - Natural draught: 0–7 kW: 300; >7–14 kW: 400; >14 kW: 600 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 300 D Below gutters, soil pipes or drains Balanced flue - Natural draught: 300 Balanced flue - Fanned draught: 75 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 75 E Below eaves Balanced flue - Natural draught: 300 Balanced flue - Fanned draught: 200 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 200 F Below balcony or car park roof Balanced flue - Natural draught: 600 Balanced flue - Fanned draught: 200 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 200 G From a vertical drain or soil pipe Balanced flue - Natural draught: 300 Balanced flue - Fanned draught: 150(2) Open flue - Natural draught: Should not be used Open flue - Fanned draught: 150 H From an internal or external corner or to a boundary alongside the terminal(3) Balanced flue - Natural draught: 600 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 200 I Above ground, roof or balcony level Balanced flue - Natural draught: 300 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 300 J From a surface or a boundary facing the terminal(3) Balanced flue - Natural draught: 600 Balanced flue - Fanned draught: 600 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 600 K From a terminal facing the terminal Balanced flue - Natural draught: 600 Balanced flue - Fanned draught: 1200 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 1200 L From an opening in the car port into a building Balanced flue - Natural draught: 1200 Balanced flue - Fanned draught: 1200 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 1200 M Vertically from a terminal on the same wall Balanced flue - Natural draught: 1500 Balanced flue - Fanned draught: 1500 Open flue - Natural draught: Should not be used Open flue - Fanned draught: 1500 N Horizontally from a terminal on the same wall Balanced flue - Natural draught: 300 Balanced flue - Fanned draught: 300 Open flue - Natural draught: Not to be used Open flue - Fanned draught: 300 O From the wall on which the terminal is mounted Balanced flue - Natural draught: Not applicable Balanced flue - Fanned draught: Not applicable Open flue - Natural draught: Not applicable Open flue - Fanned draught: 50 P From a vertical structure on the roof Balanced flue - Natural draught: Not applicable Balanced flue - Fanned draught: Site in accordance with manufacturer's instructions Open flue - Natural draught: 1500 if a ridge terminal. For any other terminal as per BS 5440: 1 Open flue - Fanned draught: Not applicable Q Above the highest point of intersection with the roof Balanced flue - Natural draught: Not applicable Balanced flue - Fanned draught: Site in accordance with manufacturer's instructions Open flue - Natural draught: Site in accordance with BS 5440: 1 Open flue - Fanned draught: 150 Notes: (1) An opening here means an openable element, such as an openable window, or a fixed opening such as a vent. However, in addition, the outlet should not be nearer than 150 mm (fanned draught) or 300 mm (natural draught) to an opening into the building fabric formed for the purpose of accommodating a built in element, such as a window frame. (2) This dimension may be reduced to 75 mm for an appliance with an input (net) not greater than 5 kW. (3) Smaller separations to the boundary may be acceptable for appliances that have been shown to operate safely with such separations from surfaces adjacent to or opposite the flue outlet.