Quick Answer

Draught-proofing a Melbourne home costs $30–$200 in materials and takes 2–4 hours as a weekend DIY job. Done properly, it cuts heating bills by 15–25% and makes rooms noticeably warmer without touching your thermostat. The biggest wins are under external doors, around sash windows, and at skirting board gaps — three areas most Melbourne homes have that leak heat all winter.

Fitting a door seal strip along the base of an external door to stop cold air draught in a Melbourne home
Fitting a self-adhesive door seal strip along the base of an external door — this single fix can account for up to 25% of heat loss in older Melbourne homes that have settled and developed gaps.

Melbourne winters are mild compared to European standards, but our houses often aren’t built for them. A standard 1960s–1990s brick veneer in Berwick, Cranbourne, or Narre Warren loses heat through gaps you can’t see: under door frames that have settled, around aluminium window frames that conduct cold, along old timber floorboards that have shrunk with decades of seasonal movement. Draught-proofing plugs those gaps for almost no money, and the results are immediate.

What You’ll Need

Item Cost Where to Buy
Self-adhesive foam door seal (10m roll, 9mm x 4mm) $8–$15 Bunnings, Mitre 10, Total Tools
Brush strip door seal (for bottom of doors) $12–$25 Bunnings, hardware stores
Door snake / draught stopper $10–$20 Kmart, Target, Bunnings
Silicone sealant (clear or white, 300ml) $10–$18 Bunnings, Reece, Mitre 10
Caulking gun $8–$20 Bunnings, Total Tools
Foam backer rod (for large gaps) $5–$12 Bunnings
Draught excluder tape (self-adhesive, clear) $10–$16 Bunnings, hardware stores
Skirting board gap filler / flexible caulk $10–$18 Bunnings, paintshops
Candle or incense stick (for draught detection) $2–$5 Supermarkets
Pro tip: Buy more foam seal than you think you need — a single external door with double-rebate frame needs 4–5 metres of tape when you do all four sides. A 10m roll ($8–$15) covers one door; buy two rolls if you’re doing three or more doors in one session.

Why Draught-Proofing Matters for Melbourne Homes

Melbourne’s SE suburbs sit on clay soil that moves with the seasons — expanding in winter wet and shrinking in summer dry. That movement creates gaps around door frames, along skirting boards, and under floorboards that simply weren’t there when the house was built. Homes in Pakenham, Officer, and Cranbourne built on reactive clay (Class M or H1 soil) can develop 5–10mm gaps around door frames within 10–15 years of construction.

Add to that Melbourne’s aluminium window frames, which conduct cold directly from outside air into the frame surround, and the old-style single-skin timber floor common in 1950s–1970s homes in Frankston, Mornington, and parts of Dandenong — and you have multiple heat loss pathways that no amount of thermostat adjustment will fix.

According to YourHome.gov.au (the Australian Government’s sustainable homes guide), uncontrolled air infiltration accounts for 15–25% of heating and cooling energy in typical Australian homes. Draught-proofing is the cheapest measure on that list, with payback periods under six months at current energy prices.

Step-by-Step Instructions

Step 1: Find All the Draughts

Before you spend a dollar on materials, map every gap in your home. On a cold, windy day, light a stick of incense or hold a candle near suspect areas. A flickering flame or smoke trail pulled toward a surface tells you exactly where the draught is entering.

Systematically check: under and around every external door, around all window frames (especially the corners), along skirting boards on external walls, where plumbing pipes or power cables enter through the floor or walls, and in the ceiling around downlights, exhaust fans, and roof access hatches.

Write a list as you go — it takes 20 minutes and saves you buying the wrong seals. Note whether each gap is large (>5mm), medium (2–5mm), or small (<2mm). That tells you whether you need backer rod + silicone, foam strip, or just draught tape.

Using a lit incense stick to detect draught under a door in a Melbourne home
Using a lit incense stick to detect draught flow under an external door — smoke bending sharply toward the gap confirms cold air is entering, pinpointing exactly where a door seal is needed.

Step 2: Seal Under External Doors

The gap under an external door is the single biggest draught source in most Melbourne homes. There are two approaches depending on the gap size and door type:

  • Brush strip seals (best for most external doors): A screw-fixed aluminium channel with a nylon brush that drags lightly on the floor. Effective for gaps up to 12mm, works on carpet or timber, and doesn’t obstruct the door swing. Cut to door width with a hacksaw, screw to the door bottom, adjust the height so the brush just contacts the floor. Cost: $12–$25, time: 20–30 minutes.
  • Self-adhesive door seals (for internal doors and light gaps): Foam or rubber compression seal that sticks to the door stop (the rebate the door closes against). Compresses when the door shuts to block airflow around the top and sides. Works only if the door closes firmly against the stop. Cost: $8–$15 per door, time: 10 minutes.
  • Door snake: The simplest option — a fabric tube you place along the bottom of the door when it’s closed. Not as effective as a fitted seal, but works for rental properties where screwing into doors isn’t permitted. Cost: $10–$20.
Pro tip: When measuring for a brush strip seal, measure the door width (not the frame opening), and check that the existing door bottom clears the floor by at least 3mm when open — a strip set too low will drag and wear the brush out within 12 months. Adjust the channel screws to set the brush height at first contact, not compressed.

Step 3: Seal Around Door Frames and Window Frames

After the under-door gap, the second biggest source is the gap between the door or window frame and the surrounding wall. In brick-veneer homes, this gap opens as the house settles and the frame pulls slightly away from the plaster.

For gaps up to 5mm: use a paintable acrylic caulk (also called “no-more-gaps”). Load your caulking gun, run a bead along the gap, smooth with a wet finger, and leave to dry. It takes paint over the top so it’s invisible when finished.

For gaps 5–15mm: push foam backer rod into the gap first (it compresses to fill the void), then run a bead of silicone sealant over the top. The backer rod prevents the sealant from being too thick — thick silicone shrinks as it cures and can crack.

Applying acrylic caulk along gap between aluminium window frame and plaster in Melbourne home
Applying acrylic caulk along the gap between an aluminium window frame and the surrounding plaster — this gap commonly opens in homes on Melbourne’s reactive clay soils and can be 3–6mm wide in houses over 15 years old.

Step 4: Seal Skirting Boards and Floorboard Gaps

In homes with suspended timber floors (common in Frankston, Mornington, and older Berwick stock), cold air rises from the subfloor through gaps in the floorboards and around skirting boards. This is one of the least visible but most impactful draught sources in winter.

For gaps between skirting and floorboards: use flexible acrylic caulk in a colour that matches your skirting (white or off-white). Run a bead along the junction, smooth with a wet finger. Do not use silicone here — silicone doesn’t take paint and can crack with the seasonal floor movement.

For gaps between individual floorboards: use a flexible wood filler or purpose-made floor filler. Apply with a putty knife, sand smooth when dry. This is especially effective in the Frankston–Mornington corridor where 1940s–1960s homes with jarrah or baltic pine floors develop significant seasonal gaps.

For the subfloor entry point where pipes come through the floor: use non-expanding foam spray (the expanding type can crack old boards). Squirt it into the gap, let it cure for 2–3 hours, then trim flush with a Stanley knife.

Step 5: Seal Ceiling Penetrations

Downlights and exhaust fans are often the forgotten draught source — particularly in 1990s–2010s homes in Pakenham, Officer, and Cranbourne that retrofitted downlights. The housing around a standard recessed downlight leaves a gap between the ceiling plaster and the light fitting.

The correct fix is a downlight cover (insulation cap) installed from the roof space — a polystyrene dome that sits over the fitting, blocking air movement between the roof space and the room below. These cost $5–$12 each and are a mandatory installation when re-insulating.

Safety warning: Never seal around downlights from below using spray foam or caulk — most recessed downlights need airflow to prevent overheating, and sealing them can create a fire risk. The correct solution is a fire-rated downlight cover installed from the roof space by someone who can safely access that space.
Safety expert showing correct polystyrene downlight cover dome to seal ceiling gaps
Showing the correct downlight cover (polystyrene dome) used to seal the gap around recessed ceiling lights — applied from the roof space, not from below, to maintain required airflow and prevent overheating risk.

Step 6: Check the Roof Access Hatch

Most Melbourne homes have a ceiling access hatch for roof space entry. These hatches are often just a piece of plasterboard sitting in a timber frame — no seal, no insulation, significant draught. On a cold morning, you can often feel cold air flowing down past the hatch edges.

Fix: Cut a piece of rigid foam insulation (50mm R1.5 polyiso or similar) to fit the top of the hatch panel. Glue it in place with construction adhesive. Then add foam compression tape around the timber frame inside the roof so the hatch panel compresses against it when closed. Total cost: $20–$40. Time: 30 minutes. Return on investment: immediate — roof spaces can be 5–10°C colder than the living space in winter.

Troubleshooting Table

Problem Likely Cause Fix
Door seal compresses too hard — door sticks Foam seal too thick for the gap Replace with thinner 3mm foam or switch to rubber P-profile seal; adjust door stop position if needed
Caulk is cracking after one season Used silicone on a surface that moves, or gap too deep without backer rod Remove cracked caulk with a scraper, install foam backer rod, re-apply flexible acrylic caulk
Brush seal drags on carpet and wears out fast Brush set too low, or wrong seal type for carpet Raise the channel with screwdriver adjustment; switch to a foam-and-seal type rated for carpet if available
Room still feels cold after sealing all gaps Underfloor or ceiling insulation missing; draught from subfloor not addressed Check subfloor insulation (R1.5–R2.0 minimum under timber floors); add door snakes to all internal doors of cold rooms as secondary measure
Draught from power points on external walls No insulation behind socket; gap in cable entry Use purpose-made draught-proof socket covers (available at electrical suppliers); do not open the socket — call an electrician for internal resealing

When to Call a Professional

DIY draught-proofing covers the vast majority of gap sources in a standard Melbourne home. Call a professional when:

  • Gaps are structural — if a door frame or window frame has separated from the wall by more than 15mm, the foundation movement is still occurring and sealing it is temporary. Get a building inspection first.
  • Asbestos is a concern — homes built before 1990 may have asbestos-containing materials in eaves linings, roof sheets, or external cladding. If you’re disturbing any fibrous material in those areas, call a licensed asbestos assessor before proceeding.
  • Subfloor work is needed — crawling under the house to seal pipes and gaps is possible DIY work, but if the subfloor is less than 400mm clearance, too wet, or has pest evidence, call a licensed builder or pest inspector first.
  • Electrical penetrations need sealing — gaps around switchboards, cable conduits, or inside power sockets must be handled by a licensed electrician. Victorian law prohibits unlicensed electrical work.

Top Tips and Gotchas

  1. Do the draught survey on a cold, windy day — gaps that are invisible on a still day reveal themselves immediately in wind. Melbourne’s westerly winds in June–July are your best detection tool.
  2. Buy more seal tape than you think — a door’s four sides take 4–5 metres of foam tape when you do it properly. Underbuying means a second trip to the hardware store mid-job.
  3. Don’t seal internal door bottoms — internal doors need some airflow for heating systems (especially ducted) to circulate properly. Seal external doors and windows only.
  4. Use acrylic caulk, not silicone, on paintable surfaces — silicone is better at the actual sealing but doesn’t take paint. Use silicone only where the gap won’t be painted (under floor cavities, pipe penetrations below the floor).
  5. Check your letter box slot — most Melbourne homes have a street letter slot in the front door that’s a direct cold air channel. A draught-proof flap or letter box cover ($8–$15) is a 5-minute fix with an immediate result.
  6. Address exhaust fans in bathrooms and kitchens — when not in use, exhaust fan vents let cold air straight in. Install backdraft dampers ($12–$20) or fan covers that close when the fan is off.
  7. Don’t over-seal your home — modern houses need some natural ventilation to avoid moisture buildup and poor air quality. The goal is to stop uncontrolled infiltration, not to make the house airtight. Ensure bathrooms and kitchens retain functioning exhaust ventilation.
  8. Check your gas heater flue — old-style open-flued gas heaters (common in Dandenong and Frankston homes built pre-2000) have a flue pipe that draws air from inside the room even when the heater is off. These units cannot be sealed. If you have one, consider replacing it with a reverse-cycle system.
Expert advice: Draught-proofing works best when paired with ceiling insulation (R3.5–R4.0 for Melbourne). The two measures together typically reduce heating bills by 35–45%, versus 15–25% for draught-proofing alone. If your home has no ceiling insulation or less than 100mm of old insulation, that’s the next logical step after addressing gaps.
Safety expert demonstrating backdraft damper for exhaust fan to prevent winter draughts in Melbourne home
A backdraft damper prevents cold winter air from flowing back in through the exhaust fan when it is off — a commonly overlooked draught source in Melbourne homes that can be fixed for under $20.

FAQ

How much can draught-proofing actually save on my gas bill?

For a typical Melbourne 3-bedroom brick veneer with multiple gap sources, expect a 15–25% reduction in heating energy use. At current Melbourne gas prices (around $1.60–$2.00/MJ for residential), that’s roughly $150–$400 per year for a household spending $600–$1,600/year on winter heating. The higher your current heating bill, the more you save from the same proportional reduction.

My house has aluminium windows — do I need special products?

Standard foam compression tape works on aluminium window frames. The key is choosing the right profile: aluminium sliding windows need pile (brush) seals on the sliding track, not foam tape — foam compresses and loses its spring within one season on a sliding sash. Look for purpose-made pile seal strips for aluminium sliding windows ($12–$20 at Bunnings or Total Tools).

Can I draught-proof rental property as a tenant?

Yes — most draught-proofing methods available to tenants are non-permanent: door snakes, self-adhesive foam tape (removes cleanly), and window insulation film. Under Victorian tenancy law, you can also request the landlord to address gaps that affect habitability. For significant gaps that affect heating (especially under external doors), submit a written repair request via your property manager — landlords are required to maintain properties to a reasonable standard of heating compliance.

What’s the difference between draught-proofing and insulation?

Draught-proofing stops uncontrolled air movement (cold air flowing in through gaps). Insulation resists heat transfer through solid surfaces (walls, ceilings, floors). Both are needed for a warm home — draught-proofing addresses infiltration, insulation addresses conduction. The two measures work together; in an uninsulated home, draught-proofing still makes a meaningful difference, but adding ceiling insulation after draught-proofing gives a much bigger combined result.

I sealed everything and the house is still cold in the morning — why?

Likely cause: inadequate or absent ceiling insulation, or the heating system is too small for the floor area. Draught-proofing reduces ongoing heat loss, but if you’re starting from a very cold overnight temperature (common in Pakenham, Officer, and Cranbourne where overnight lows of 3–5°C are common in July), the house will still take time to warm up in the morning. A programmable thermostat set to start heating 30–60 minutes before you wake up solves the morning cold without increasing total energy use.

Is there government rebate for draught-proofing in Victoria?

Draught-proofing itself is not currently a rebated activity under the Victorian Energy Upgrades (VEU) program — that program focuses on appliance replacement and insulation installation. However, the Victorian Government’s energy assistance programs include bill relief and appliance upgrade rebates that reduce overall heating costs. For low-income households, the Concession Card holders’ rebate and the Utility Relief Grant Scheme may also apply.

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