An older Illawarra house gets air moving by giving it a path through the building, so the fix is usually about where the openings are, not about adding equipment. Many post-war homes were built as a string of small rooms with doors that stay shut and windows that open onto one side only. A renovation that already touches walls, windows and ceilings is the cheapest time to correct that.
The guidance below draws on the Australian Government's Your Home passive cooling guide, applied to how older coastal houses are laid out.
What does a house need to get air moving through it?
Your Home says air movement needs well-designed openings (windows, doors and vents) and unrestricted breeze paths. That means a window on one side, an opening on the other, and a clear route between them.
Older houses fail this in two ways. Rooms with a single window have nothing to draw air through, and rooms that do have openings on two sides are cut off from each other by internal doors that stay closed for privacy. Both are layout problems, and both can be changed without changing the footprint of the house.
Which openings should be larger?
Your Home recommends larger openings on the leeward (low pressure or downwind) side of the house and smaller openings on the windward (high pressure or upwind) side. Air does not blow straight through a building. It is drawn towards areas of lower pressure, so a big opening on the sheltered side pulls it through.
On the Illawarra coast that makes the direction of the prevailing breeze on your block the first thing to identify. The same guide notes that a site usually has a limited range of directions from which beneficial cooling breezes arrive, and that these should be identified before design decisions are made. A window that looks like the obvious one to enlarge may sit on the wrong side.
How do you get air through closed internal doors?
Your Home suggests a louvre or awning window above internal doors so breezes can pass through the building while privacy and security are kept. In a bedroom wing or a hallway of small rooms, this lets air cross the house without anyone leaving doors open.
This is a framing job as much as a joinery one. If a wall is being altered anyway, the opening can be built in while the lining is off. If you are taking out a wall to open up the plan, our post on removing a load-bearing wall covers when that is a quick job and when it needs an engineered beam.
What does stack ventilation add?
Warm air rises, and if it has somewhere to go it leaves the building through high-level windows or vents, drawing cooler air in from lower openings. Your Home lists high-level windows and ceiling or roof space vents as ways to make use of this.
In an older house that points to the ceiling and roof space. A skylight or roof window that opens can serve as the high outlet, and our post on skylights, glazing and borrowed light covers what each type suits. Hot air trapped in a roof space with no outlet is a separate problem worth raising with the builder before ceilings are closed up.
Do ceiling fans help?
Yes, as a supplement. Your Home says that in a lightweight building in a warm temperate climate, ceiling fans in bedrooms and all living areas significantly reduce cooling energy use, and that using them with air-conditioning makes it more effective. They move air within a room, so they do not replace a path for air to enter and leave.
Fans need a ceiling that suits them. If ceilings are being lined or lowered, the fan positions are worth deciding before the plasterboard goes up, and wiring is far easier to run at that point.
What about bathrooms and laundries?
A room with no external wall relies on mechanical extraction. The fan has to be ducted to discharge outside the building, since moisture released into the roof space only moves the problem. Our post on adding a second bathroom or ensuite explains why this matters for rooms carved out of the middle of a house, and the same applies to a laundry without a window.
Where ventilation fits in a renovation
The work that improves airflow is the same work a renovation already involves: altering walls, replacing windows, lining ceilings and running wiring. Deciding on airflow at the start means the openings are framed once rather than cut in later. Salt air and coastal weather also affect which window and vent hardware lasts, a point covered on our home renovations page.
If you have a closed-up older house and a renovation in mind, send the details through the contact page or call 0434 037 851. We will look at how the rooms connect and where the openings could go.
Common questions
- How do you get air moving through an older house?
- Give the air a path from one side of the house to the other. The Australian Government's Your Home guide says air movement needs well-designed openings and unrestricted breeze paths, so closed internal doors and furniture in the way work against you. Openings in rooms on opposite sides of the house, plus a way for air to pass through the rooms in between, do most of the work.
- Which windows should be bigger, the windward or the leeward ones?
- The leeward ones. Your Home recommends larger openings on the leeward (low pressure or downwind) side of the house and smaller openings on the windward (high pressure or upwind) side, because air is drawn towards low pressure rather than blown through.
- Do ceiling fans help ventilation?
- They move air inside the room rather than bringing fresh air in. Your Home says that in a lightweight building in a warm temperate climate, ceiling fans in bedrooms and living areas significantly reduce cooling energy use, and that they make air-conditioning work better when both are in use.
- How can I keep a bathroom or internal room ventilated?
- A room with no external wall needs its extraction designed in, with the fan ducted to discharge outside the building. A bathroom fan that vents into the roof space moves the moisture to a different part of the house. Our second bathroom post covers this in more detail.
Want a hand with this at your place? Get a free quote or call 0434 037 851.