Chris Irwin - Good Homes Alliance

Chris Irwin MCIBSE.CEng BSc.PhD
Inadequate Ventilation causes poor IAQ in New
& Existing Homes.
 1 in 5 Homes suffer from Condensation &
Mould.
 Two Categories:
 “Nuisance” Condensation : on windows,
wallpaper pattern staining
 “Severe” Condensation: mould growth &
spore release, structural damage.
Demand Controlled Ventilation can help !!!
DEFINITION:
 Demand Controlled Ventilation (DCV):
Providing regulation to the ventilation system
on a room by room basis; dependant upon the
local environment & without user intervention
(automatic).
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Occupancy driven
Activated by humidity or CO2 levels on a room
by room basis
Self regulating
A combination of Extract & Background
ventilation system OR Extract & Supply
ventilation system.
The objective of DCV is to reduce the energy
usage of the ventilation system whilst
maintaining a healthy living environment.
There is no benefit in saving energy if air
quality and occupant comfort is affected
New Build
DCV PSV
DCV MEV
DCVMVHR*
Refurbishment
DCV PSV
DCV MEV
* House air leakage rate < 3m3/hr/m2 @ 50 Pa
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No user intervention
Whole life costing (PSV)
low maintenance
Easy & economic to install
Energy efficient/Reduced heat loss
Quiet operation
Does not over ventilate & provides Zoned
Control
Good IAQ
Controls condensation & mould
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Increased levels of loft, cavity & external wall
insulation in new & refurbished properties
significantly reduce building envelope leakage
rates.
As whole house ventilation rates reduce, houses
become less forgiving in dealing with relative
humidity & VOC’s, the correct, adaptive
ventilation strategy becomes an absolute priority.
DCV lends itself to all houses as it automatically
adapts to an occupants usage profile.
DCV achieves significant energy savings whilst
maintaining a healthy living environment
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THANK YOU