Knowledge/Gas safety and CO/Sealing a house that still has an open-flued heater
Sealing a house that still has an open-flued heater
Open-flued heaters need fixed ventilation to burn safely, and draught proofing takes it away. From 1 July 2027 Victorian rentals have to be draught proofed on external doors, windows and wall vents. Separately, the regulator's sealing list explicitly includes evaporative cooler vents. Seal those in a house with an open-flued heater and that's a carbon monoxide (CO) risk.
- Rental draught proofing
- 1 Jul 2027on a new lease
- On the sealing list
- Evap ventsplus wall vents, flues, exhaust fans
- Open-flued needs
- Fixed ventor it spills
- Who pays for it
- VEUVictorian Energy Upgrades funds draught proofing
Why do these two jobs fight?
The Building and Plumbing Commission (formerly the Victorian Building Authority, or VBA) lists what gets sealed during energy efficiency work. Doors, windows, unsealed wall vents, chimneys, flues of open fireplaces, exhaust fans and evaporative cooler vents are all on that list, by name.
Its own warning puts the problem plainly. If a home has a flueless or open-flued gas space heater, take special care when draught proofing and weather sealing. Those heaters need a certain amount of fixed ventilation. In the regulator's words, "Weather sealing and draught proofing upgrades in homes can reduce ventilation, increasing the risk of carbon monoxide poisoning."
Energy Safe Victoria goes further. It says open-flued technology is incompatible with newer, better sealed, energy efficient homes.
Why is this about to land on you?
Two things arrive at once. From 1 July 2027 Victorian rental properties must have draught proofing installed on external doors, windows and wall vents on a new lease. And the VEU pays for draught proofing, so it's likely to be done at volume, whether or not anybody checks what's burning in the lounge room.
Sealing the evaporative ceiling vents in a house that still has an open-flued gas heater is a recipe for carbon monoxide. It may well be done by somebody who's never been trained to think about combustion air, on a house where nobody's done a negative pressure and spillage test on the heater.
What should you do about it?
- Ask what's burning before you seal anythingIf the house has a flueless or open-flued gas appliance, the draught proofing scope changes. That's a two-minute question at quoting stage and a very expensive one later.
- Test for negative pressure after the sealing, not just beforeThe house you tested isn't the house you're handing back. Sealing changes the result, which is the whole point of the concern.
- Put the combustion air back as fixed ventilationNot as a gap under a door that the next tenant blocks with a draught snake. Fixed, sized and documented.
- Write it on the paperworkIf you sealed a house with an open-flued appliance in it and tested the appliance afterwards, say so in writing. That record is the difference between doing the job properly and being able to show you did.
How do you explain this to a landlord?
Most people quoting rental compliance work in 2027 are likely to quote draught proofing as a line item. Few will be able to explain why the heater matters to it.
If you can walk a landlord or an agent through that in plain language, you're not competing on the price of some door seals any more. You're the one who spotted the thing that could have hurt their tenant.
Found something on site you're not sure about?
Gas safety is the one area where the right answer and the comfortable answer aren't always the same, and you're the one holding the licence.
If you've got a job you're weighing up, Kevin's happy to talk it through.
Who this is for: small and medium HVAC contractors in Victoria. If you're a homeowner after a rebate or a repair, you need a licensed contractor, not us, and yours can point you the right way.
Related
- How a negative pressure and carbon monoxide spillage test runsEnergy Safe Victoria's four-stage test from GIS 38, where the probe goes, why the pass mark isn't a ppm figure, and how to size the ventilation fix.
- The ventilation rule changed on 31 March 2014The building's approval date decides it. Before 31 March 2014 it's 1 m³ of room per 3 MJ/h. From then, an open-flued appliance needs 1 m³ per 0.4 MJ/h.
- What to do when a customer won't fix an unsafe heaterFour steps in order, with the numbers to call. Notify the Building and Plumbing Commission properly and it won't take enforcement action against you.
- Every open-flued space heater under a Victorian alertSix heater families under a safety alert, with brands and phone numbers, the one you isolate instead of servicing, and what the 2022 sales ban caught.
Review date: 1 March 2027. Figures in this area change without much notice and this page carries some that will go stale. Every number above is dated and sourced so you can check it yourself. If you find something out of date here, tell us and we will fix it.