Sub Floor Ventilation Calculation

Subfloor ventilation the 2005 branz house condition survey found 38 of homes with suspended timber floors had less than half the subfloor ventilation required by the current building standards.
Sub floor ventilation calculation. Unfortunately sub floor ventilation is often a forgotten part of termite management. Timber queensland limited technical data sheet 14 sub floor ventilation revised february 2004 page 3 ventilation efficiency. The space under a suspended timber framed floor must be ventilated. Rytons underfloor ventilation calculator for effective sub floor ventilation.
Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. Squared nett ventilation per lineal metre on both external and internal walls. A clear opening area of 3500 mm 2 100 x 35 mm should be provided for every square metre of floor area. Obstacles that prevent air flow to and from vents will reduce the efficiency of the sub floor ventilation system.
How many vents are needed. The wall is 12 metres long and the opening size of each vent is 14 200 mm 2. See if you can calculate the number of vents needed in a wall. This inadequate ventilation can cause some serious problems.
As a rough estimate a 100w motor will cost approximately 51 to run annually for 4 hours per day. 2 requires the sub floor between a suspended floor and the ground to be ventilated. 3600 specifies that the minimum requirement for sub floor ventilation should be one 1 ventilator of 8 400 mm. Typically subfloor systems are energy efficient to calculate the annual cost of operating one look at the motor wattage.
My concerns began with our pre purchase survey it was a bit of a cut and paste job to be honest and stated the obligatory inadequate sub floor ventilation possible sub floor rot better get an expert in to check blah blah 146. Subfloor space is undertaken annually as part of normal house maintenance. Let s say you re inspecting a building in climate zone 2 and the subfloor walls have wire mesh air vents. This minimises sub floor moisture which helps to prevent timber decay and creates an environment that discourages termite attack.
The sub floor space must be free from all building debris and vegetation. A minimum of five air changes per hour should be provided and double that for wet subfloor spaces. Openings should be provided within 750 mm of. Of the australian standards a s.