Before replacing every window or buying a larger heater, spend some time identifying where unwanted air enters your older home. A draught beside the sofa can make one corner uncomfortable even when the room temperature seems reasonable. Finding the path of that air is a more useful starting point than ordering a bag of seals and treating every opening alike.
Draught proofing should be planned alongside ventilation. The Australian Government’s Your Home guidance distinguishes deliberate fresh-air provision from unintended leakage. An older house needs a considered approach to both, especially when a renovation changes windows, exhaust systems or heating. The goal is a comfortable, usable home with appropriate ventilation, rather than a collection of openings sealed without understanding their purpose.
Start with a room diary, not a shopping list
Walk through the rooms you use most and record where you notice moving air. Note the time, weather, whether windows and doors are closed and which appliances are operating. A photograph of the location is often more useful than a long description written later.
Separate observations from conclusions. “Cold air felt beside the bedroom skirting during windy weather” is an observation. “The entire floor needs replacement” is a conclusion that has not yet been established. Keeping the distinction helps a tradesperson investigate the actual issue without being directed toward an unnecessarily large job.
Use accessible visual checks only. Do not remove electrical fittings, enter unsafe roof spaces or disturb unknown old materials to trace a draught. Avoid flames or improvised smoke tests around the house. Where the air path is concealed or the problem persists, arrange a suitably qualified building assessment.
A room diary also creates a useful baseline for a sustainable renovation plan. It can help you decide which small repairs should happen before larger building changes are specified.
Identify openings that must not be treated as ordinary gaps
Before anyone starts sealing, identify ventilation openings, drainage paths, appliance provisions and access panels. They may look like inconvenient holes, but their function must be understood. Your Home specifically warns against blocking subfloor vents and notes that some gas appliances require fixed ventilation.
Arrange the appropriate assessment where fuel-burning appliances, fireplaces or complex exhaust arrangements are present. Ask the relevant qualified trade how the proposed changes interact with the appliance and its ventilation requirements. A draught sealing contractor should not make independent alterations to gas, electrical or flue systems.
For apartment entry doors, fire or smoke door assemblies and specialist window systems, obtain advice before adding or replacing seals. The detail needs to preserve the door or window’s intended operation and any applicable performance requirements. A readily available adhesive strip is not automatically suitable for every opening.
Create a “check before sealing” list
- Permanent ventilation openings whose purpose has not been confirmed.
- Gas heaters, fireplaces and associated air or flue provisions.
- Exhaust fans, rangehoods and their discharge arrangements.
- Window drainage slots and external wall drainage details.
- Doors with fire, smoke, security or accessibility functions.
- Concealed service penetrations requiring qualified trade access.
Assign a person to resolve each uncertain item
A list of warnings alone does not advance the renovation. Beside each uncertain item, record who will assess it and when the answer is needed. This turns a vague concern into a specific decision before materials are purchased.
Repair window operation before adding seals
Begin with the condition of the window. Does it close squarely? Do the handles and catches engage normally? Is a sash damaged or a frame visibly out of alignment? A sealing proposal should acknowledge those issues instead of assuming that a thicker strip will compensate for every defect.
Ask the repairer to demonstrate normal operation after the work. A window that is difficult to close may be left ajar in daily use, undermining the reason for the upgrade. The seal should be selected for the particular opening style and the manufacturer’s or repair specialist’s guidance.
Retaining original windows can be a reasonable renovation choice where their condition supports repair. Our guide to restoring timber sash windows explains the wider repair decisions. Draught proofing can be one part of that scope rather than a reason to discard a sound window.
If glazing is being upgraded, specify the frame and installation details as well as the glass. A quotation focused exclusively on glass performance leaves the perimeter work uncertain. Ask how the installer will finish the junction between the window assembly and the surrounding wall.
Treat external doors as complete working assemblies
An external door has a leaf, frame, threshold, hardware and adjoining finishes. Inspect how they work together. A local gap at one corner may relate to a repair or adjustment, while the bottom edge may need a different product from the sides.
Describe the finished outcome in practical terms: the door closes without unusual force, the latch engages, the threshold remains usable and the agreed draught path is addressed. Consider everyone who uses the entrance, including children and people with limited hand strength or mobility.
Do not choose a threshold detail purely because it looks substantial. Ask whether it creates a trip concern, catches on the floor finish or complicates weather protection. If the door itself needs replacing, include these questions in the front door replacement brief before the new unit is ordered.
Check the completed work with the door in normal daily use. An installation that appears satisfactory with a carefully positioned door may behave differently when someone carries shopping inside or operates it with one hand. Practical usability belongs in the acceptance check.
Use renovation access to address concealed junctions
Some unwanted air paths are easier to investigate when architraves, linings or cladding are already being removed for another reason. Tell the builder that air sealing is part of the brief before those surfaces are closed. Otherwise, a useful opportunity can disappear behind freshly painted finishes.
Ask for a marked plan of the junctions to be addressed. The detail should name compatible materials and identify the person responsible for the work. “Seal as required” gives little assurance when several trades assume someone else will complete it.
Service penetrations need appropriate trade coordination. A plumber’s new pipe route, an electrician’s alteration and an air-conditioning installation may each affect the building enclosure. The work should include the agreed finishing detail around the penetration, with photographs before concealment where practical.
For a broader recladding project, discuss the continuity of the proposed exterior wall wrap and its junctions with the designer. That is a construction detail requiring suitable products and moisture consideration, rather than an invitation to cover every surface with the same tape.
Do not confuse a cold surface with an air leak
A room can feel uncomfortable even when no obvious draught is present. Record whether you feel moving air, a cold surface nearby or a general inability to maintain comfort. These observations may point the assessor toward different questions.
For example, a cold window and an air leak beside the frame can coexist, but they are not the same problem. Sealing a perimeter gap does not change the glass specification. Conversely, replacing glass does not automatically resolve an unrelated opening around an old service penetration.
Use the assessment to set separate scopes where necessary. If moisture appears on glazing after changes to the house, investigate it rather than assuming the sealing has simply been done “too well”. Our guide to window condensation discusses the broader renovation decisions.
Consider a professional leakage assessment for a larger retrofit
When many rooms are affected or substantial work is planned, ask whether a professional air leakage assessment would help prioritise the project. Your Home describes blower-door testing as a way of measuring airtightness. A useful service should also explain the practical meaning of the results and help locate relevant leakage paths.
Request a written scope before booking. Clarify whether the service includes a room-by-room investigation, a numerical test, a repair schedule or a follow-up test. These are different deliverables. A number without interpretation may not tell the builder what to change.
Ask the assessor how the house will be prepared and how appliances will be managed safely. Follow their instructions; do not improvise test conditions yourself. If testing is repeated after renovation, ask whether the conditions are sufficiently comparable to support the conclusions being drawn.
Build a small, transparent AUD budget
The following is an illustrative planning exercise using invented amounts in AUD, including GST. It is not a current price guide. Assume a homeowner is planning a limited first stage covering selected doors and windows after their condition has been assessed.
Allow AUD $250 for the agreed assessment, AUD $280 for nominated sealing materials and AUD $650 for installation and minor adjustments. That produces an illustrative subtotal of AUD $1,180. Keep a separate AUD $220 allowance for an optional follow-up visit if the agreed scope warrants it, bringing the planned maximum to AUD $1,400.
These figures exclude major joinery repairs, appliance work, electrical alterations and whole-house testing unless specifically included in a real quotation. If a door needs rebuilding, price that repair separately. The homeowner should be able to see which expenditure addresses the draught and which restores a defective building component.
Before accepting an offer, compare the number and type of openings, exact materials, preparation and completion checks. Our quote comparison guide can help you avoid comparing a supply-only pack of seals with a complete repair and installation service.
Set a sensible order for the work
Begin with the observations and the items requiring specialist assessment. Resolve damaged or poorly operating components next. Then complete the agreed sealing work and review the result before expanding the scope.
This sequence avoids paying twice. There is little value in fitting new seals to a window scheduled for repair next month, or finishing a perimeter before another trade removes the surrounding lining. If the renovation timetable is uncertain, choose a clearly defined interim measure and record its expected lifespan.
Keep the first stage small enough to assess. A well-documented bedroom and living-room project can reveal whether the chosen approach suits the house. If the result is useful, extend the same decision process to other rooms, adapting details where the construction differs.
Make the handover specific to each opening
Ask the contractor to walk through the completed openings with you. Identify which seals were replaced, which components were adjusted and which observations still need attention. If a repair was deferred, the record should say so plainly rather than describing the whole room as finished.
For an illustrative bedroom window, the handover might record a repaired catch, a named perimeter seal and a remaining joinery issue referred for separate assessment. For the front door, it might record the selected bottom seal and an agreed check after the nearby flooring is replaced. The point is to preserve the actual decisions, not to produce an elaborate report.
Also agree who to contact if a new seal detaches or the opening becomes difficult to operate. Keep that contact with the invoice and product details. A minor problem is easier to resolve while the installation is recent and the scope is clear. Do not respond by repeatedly adding extra layers of material to compensate for an unexplained change in the door or window.
Review comfort and operation after the changes
Repeat your room diary during similar weather and normal household use. Note remaining draught locations, changes in window or door operation and any new concerns about stale air or moisture. These observations are a reason to contact the relevant professional, not a basis for sealing additional openings indiscriminately.
Keep product information and photographs of concealed work. Where a seal is replaceable, record its type so maintenance does not become guesswork. Tell later trades about the air sealing work when they alter nearby services or finishes.
A successful draught proofing project is easy to describe afterwards: the unwanted air paths were identified, the appropriate repairs were completed, essential building functions were considered and the rooms remain practical to use. That clarity is a strong foundation for whatever renovation comes next.