Products: Roof Terminals

Breathing Buildings offer two roof terminal options ⇒ Penthouse Louvre or Mushroom Cowl.

0127 RTThe penthouse louvre is most frequently associated with a natural ventilation system. We offer a double bladed system, with corner posts and gabled roof as standard. This terminal offers Class-A weather performance under normal driving rain conditions, and enhanced weather performance can be specified if required. The aluminium louvre blades are mill-finish as standard, although any RAL colour can be selected.

Mushroom R-SeriesThe mushroom cowl is a popular alternative to the traditional metal blades of the penthouse louvre. The mushroom offers better noise attenuation properties than the penthouse, and demonstrated significantly better weather performance during independent tests. The terminal is finished in RAL 7035 (Light Grey) as standard but other colours are available on request.

Both terminals offer optional acoustic attenuation.

Installation

 

The roof termination is supported on and secured to a weathered builders curb around the perimeter of the roof penetration and shaft (to the e-stack unit below). This overcurb should be a minimum height of 150mm above the finished roof surface.

 

Shaft

 

R-Series

R-Series Mushroom building assy 001 (2)

An insulated shaft needs to be constructed by others between the bottom of the roof termination and the R-Series unit. A rubber seal is provided on the top of the e-stack unit, to ensure air tightness with the bottom edge of the shaft. Breathing Buildings has no preference as to the material of the shaft. Previous examples have utilised the concrete soffit, plywood, plasterboard, and ductwork. The shaft should be sized to fit the damper section of the e-stack R-Series unit.

The shaft is to be divided vertically into two pathways, for separation of inflow and outflow. Usually this shaft divider is constructed from either plywood, or insulation board. Note that the split is not equal, with the larger section above the fan of the e-stack unit.

 

S-Series

 

An insulated shaft needs to be constructed by others between the bottom of the roof termination and the R-Series indoor unit. A rubber seal is provided on the top of the e-stack indoor unit to ensure air tightness with the bottom edge of the shaft. Breathing Buildings has no preference as to the material of the shaft. Previous examples have utilised the concrete soffit, plywood, plasterboard, and ductwork. This is sized to fit the damper (1500mm x 1500mm).

When a mushroom termination is used, a square duct separates the fresh air from the exhaust within the shaft. The duct is located in the corner of the shaft forming an ‘L’ shape in plan view, and is orientated so it matched similar dividers inside the mushroom termination and S-Series unit. The shaft divider starts and finishes at curb level (just underneath the roof termination). The divider shaft cannot be supported on top of the e-stack damper.

 

Weather Performance

 

Water testing has been carried out at the BRE using test method prEN 15601 – Hygrothermal performance of buildings – resistance to wind driven rain coverings with discontinuity laid small elements. The terminal was subject to 75mm/hr/mat a driving wind speed of 30mph (13.4 m/s). Water ingress during the tests was too small to measure in meaningful terms.