Common Problems with Double Glazed Doors and How to Avoid Them
Double glazed doors promise warmer winters, quieter interiors and lower energy bills, so it is genuinely frustrating when fogged glass, draughts or stiff tracks turn up a few years down the track. Most of these problems are not inevitable. They are the result of a rushed installation, the wrong product spec, or a seal that was never going to last. If you are researching double glazed doors and windows for a Macarthur home near Camden Valley Way, this guide will help you understand what can go wrong, why it happens, and exactly what to look for before you sign anything.
- Key Takeaways
- What is double glazing and why do doors need special attention?
- What are the most common problems with double glazed doors?
- How do you compare glass types for double glazed doors?
- What mistakes do homeowners make when buying double glazed doors?
- DIY versus hiring a professional: which is right for double glazed doors?
- How does a professional installation actually work?
- When is double glazing NOT the right choice for a door?
- Practical maintenance tips to protect your double glazed doors
- Ready to get your double glazed doors right the first time?
- FAQ
Key Takeaways
- Seal failure is the single biggest cause of fogged or hazy double glazed door panels, and it is almost always an installation or product-quality issue.
- Condensation inside the room is normal in cold weather; condensation between the two panes means the IGU seal has broken down.
- Stiff tracks and misaligned frames are largely preventable with correct measure-up, quality rollers and proper installation.
- Glass type matters: Low-E, toughened, and laminated glass each suit different applications and choosing the wrong one creates both comfort and safety issues.
- Professional installation protects your BASIX compliance, your warranty, and your resale value, double glazing is not a DIY project.

What is double glazing and why do doors need special attention?
Double glazing means two panes of glass separated by a sealed air gap (typically 6 mm to 20 mm wide), which together form what the industry calls an insulated glass unit, or IGU. That trapped air or inert gas (usually argon) slows the transfer of heat and noise far more effectively than a single pane alone. According to the Australian Government’s Your Home guide, glazing can account for a significant share of a home’s heat gain and loss, making the quality of the seal and the frame critical.
Doors face extra stress compared to fixed windows. They swing, slide or stack. Hardware wears. Frames flex slightly every time the door operates. That mechanical movement puts the IGU seal and the frame under repeated load, which is exactly why a correctly specified, professionally installed double glazed door matters so much.
What are the most common problems with double glazed doors?
After years of work across Macarthur and South West Sydney, the same five issues keep cropping up. Understanding each one makes it much easier to ask the right questions before you buy.
1. Fogged or hazy glass between the panes
This is the most visible and most common complaint. When the hermetic seal around the IGU breaks down, humid air enters the cavity and condenses on the inner surfaces of the glass. The result is a permanent fog or hazy smear that cannot be cleaned because it is trapped between the panes. Once the seal is gone, the entire IGU needs replacing, there is no patch fix.
Seal failure is caused by low-quality sealant, incorrect installation (the frame was not square or the unit was stressed during fitting), or an IGU that was simply not up to Australian conditions. Macarthur summers regularly push well above 35°C, and that thermal cycling accelerates seal degradation in budget-grade units.
2. Condensation in the wrong place
Condensation on the room-facing surface of a double glazed door during a cold morning is normal and is not a fault. It simply means the interior glass surface has dropped below the dew point of the warm, humid air inside. Better thermal performance (lower U-value glass, such as Low-E coated panels) reduces how often this happens.
Condensation between the panes, as described above, signals a seal failure. Condensation on the outside surface in cool weather is also normal, it means the outer glass is very cold, which is actually a sign the IGU is doing its job well. Knowing which type you are dealing with saves a lot of unnecessary worry.
3. Stiff, hard-to-operate doors
Double glazed panels are noticeably heavier than single-glazed equivalents. Sliding doors especially need rollers and tracks that are rated for the extra weight. Cheap or incorrectly sized rollers wear quickly, the door drops slightly, and within a year or two it drags, jams, or requires a hard shove to open. This is almost entirely avoidable with the right hardware specification from day one.
Bi-fold and stacking door systems have additional pivot points and hinges that must be rated for repeated use under load. When a door is installed even slightly out of square, every operation puts uneven stress on those components.
4. Draughts and air leakage
A double glazed door that lets in cold air or wind noise around its edges is often a weatherstripping problem. The brush seals, rubber gaskets and wool pile around the frame and sash need to create a continuous, compressed barrier. If the door was not installed square and level, or if the brushes were the wrong pile height for the gap, you will feel it on a windy night, no matter how good the glass is.
5. Frame distortion and water ingress
Aluminium frames that were not correctly fixed to the structural opening, or that were installed without adequate support, can rack (twist slightly out of square) over time. Once a frame racks, the IGU is under stress, the weatherstripping no longer seals evenly, and water can track in through the corners or sill. In severe cases, the glass itself can crack from frame pressure.

How do you compare glass types for double glazed doors?
Choosing the right glass type for your double glazed doors is one of the most important decisions you will make. Each option has a different job.
| Glass Type | Best For | Key Benefit | Typical Use |
|---|---|---|---|
| Low-E (low emissivity) | Energy performance | Reflects radiant heat, lowers U-value | Living rooms, alfresco doors |
| Toughened safety glass | High-traffic or safety zones | Shatters into small blunt pieces | Entry doors, near stairs |
| Laminated glass | Security and noise | Holds together when broken | Street-facing doors, BAL zones |
| Tinted glass | Solar control and privacy | Reduces glare and heat gain | North and west-facing doors |
| Obscure glass | Privacy | Diffuses view while passing light | Bathrooms, side entries |
For Macarthur homes in new estates like Oran Park or Gregory Hills, BASIX often steers the glass choice. For established homes in Camden or Narellan, heritage or streetscape considerations sometimes influence frame colour and profile. A good supplier will walk you through the WERS data for each option so you can make an informed choice, not just a guess.
What mistakes do homeowners make when buying double glazed doors?
After working across the Macarthur region since 2009, the team at Newage Glass and Aluminium has seen the same avoidable mistakes come up repeatedly. Here are the ones worth knowing before you start shopping.
- Choosing on price alone: a cheap IGU with a low-grade sealant will fail faster in Australian thermal conditions, often within a few years.
- Not asking about the WERS rating: without a verified energy rating, you cannot confirm the door contributes to BASIX compliance, which can cause issues at inspection.
- Skipping the measure: ordering stock-size double glazed doors for an opening that is not perfectly square is a recipe for gaps, draughts and frame stress.
- Ignoring hardware weight ratings: rollers, hinges and locking mechanisms must be rated for the extra mass of a double glazed panel.
- Assuming all aluminium frames are the same: thermally broken aluminium frames (with an insulating barrier inside the frame section) perform significantly better than standard aluminium in terms of condensation on the frame itself. Ask your supplier which system they use.

DIY versus hiring a professional: which is right for double glazed doors?
Replacing a double glazed door is not a standard weekend project. Here is an honest breakdown of why that matters.
A double glazed sliding or hinged door typically weighs two to four times what a standard single-glazed door weighs. Getting it into a structurally sound opening requires the right tools, the right people, and knowledge of how to set the frame square and plumb to within very tight tolerances. Get it even slightly wrong and you have created most of the problems listed above before the door has been used once.
There are also compliance considerations. In NSW, installation of windows and doors as part of a renovation or new build may require a licensed contractor under the Home Building Act, and certain work triggers the need for a BASIX certificate or council approval. NSW Fair Trading provides guidance on when licensed work is required, it is worth checking before you start. You can find more information at NSW Fair Trading.
Resale value is another real consideration. Buyers and valuers notice quality. A professionally installed, correctly specified double glazed door with documented WERS compliance adds credibility to your renovation. An amateur install with no paperwork does the opposite.
The honest verdict: general maintenance like cleaning tracks, lubricating rollers, and replacing worn brush seals is absolutely something a capable homeowner can handle. Anything involving the frame, the IGU, or structural alterations to the opening belongs with a licensed professional.
How does a professional installation actually work?
A correctly managed double glazed door project follows a clear process. Here is what to expect when you work with a specialist like Newage Glass and Aluminium, a family-run business that has been designing, manufacturing and installing aluminium doors and windows across the Macarthur region from its workshop in the Smeaton Grange Industrial Estate on Blackmore Road since 2009.

When is double glazing NOT the right choice for a door?
Honest answer: double glazing is almost always the better long-term choice for external doors in the Macarthur climate. But there are situations where it may not be the priority.
If you have a heritage-listed property or a home on a heritage streetscape in old Camden, council may restrict the frame profile depth or glass thickness you can use. Double glazing may still be achievable, but the profile choice will be constrained. Check with Camden Council before specifying.
For a purely internal door between conditioned spaces (such as an office partition), single glazing may be perfectly adequate for acoustic separation. The sliding door options across the Macarthur region include both single and double glazed configurations, and a good specialist will recommend the right spec for each opening rather than defaulting to the most expensive option every time.
Practical maintenance tips to protect your double glazed doors
Even a perfectly installed double glazed door benefits from basic upkeep. These habits protect both the IGU seal and the hardware.
- Clean tracks monthly: dirt and grit in the track act like sandpaper on rollers, accelerating wear and making the door progressively harder to operate.
- Lubricate rollers and hinges annually: use a silicone-based lubricant, not oil-based products that attract more dust.
- Check weatherstripping every year: brush seals compress over time. Replacing worn pile strips is inexpensive and makes a noticeable difference to draughts and noise.
- Keep sills clear of water pooling: standing water against the frame base accelerates sealant breakdown at the base of the IGU.
- Do not force a stiff door: if it is suddenly hard to open, investigate the cause. Forcing it stresses both the hardware and the IGU.
The Australian Window Association also publishes guidance on window and door maintenance that is worth bookmarking for general reference.
Ready to get your double glazed doors right the first time?
The Newage Glass and Aluminium workshop sits in the Smeaton Grange Industrial Estate, just off Camden Valley Way and a short drive from Narellan Town Centre, making it easy for the team to reach homes across Harrington Park, Currans Hill, Camden and the wider Macarthur region. The business also supplies and installs across South West Sydney suburbs from the one local workshop, so you are dealing with the same team from measure to installation.
If you are planning a renovation and want to avoid the common problems with double glazed doors, the most practical first step is a free, no-obligation measure and quote. The team will assess your opening, walk you through the glass and hardware options that suit your home and your budget, and give you a written figure based on reality, not a guesswork ballpark. Book your free measure and quote with Newage Glass and Aluminium today; it costs you nothing and gives you a clear, honest picture of what your project actually involves.
FAQ
How much do double glazed doors cost in NSW?
The cost of double glazed doors in NSW varies considerably depending on the door type (sliding, hinged, stacking), the size of the opening, the glass specification (Low-E, toughened, laminated), the frame colour and profile, and the complexity of the installation. A free measure and quote from a local specialist like Newage Glass and Aluminium is the only reliable way to get an accurate figure for your specific project.
Why is there condensation on my double glazed door?
Condensation on the inside surface of your door is normal in cold weather and means warm interior air is hitting a cool glass surface. Condensation between the two glass panes is a different matter entirely, it means the IGU (insulated glass unit) seal has broken down and humid air has entered the cavity. A failed IGU seal requires the glass unit to be replaced; it cannot be cleaned or patched.
Do I need council approval to replace double glazed doors in NSW?
In many cases, a like-for-like door replacement does not require council approval, but it depends on your property type, the size of the change, and whether a BASIX certificate applies to your renovation. Heritage-listed properties and certain strata buildings may have additional requirements. Always check with your local council or a licensed builder before starting work, as requirements vary.
How long does it take to get double glazed doors made and installed?
Custom aluminium double glazed doors typically take a few weeks from the confirmed measure to installation, depending on the complexity of the job, the glass specification required, and the current production schedule. Your supplier should give you a realistic lead time in writing at the quote stage so you can plan your renovation accordingly.
What glass options are available for double glazed aluminium doors?
Common glass options for double glazed aluminium doors include Low-E coated glass for improved thermal performance, toughened safety glass for high-traffic or child-safe areas, laminated glass for security and noise reduction, tinted glass for solar control, and obscure glass for privacy. The right choice depends on the door's orientation, your BASIX requirements, and whether the property is in a bushfire-prone area. A specialist will help you match the glass type to your situation.
Does Newage Glass and Aluminium make and install the doors themselves?
Yes. Newage Glass and Aluminium designs, fabricates and installs aluminium windows and doors from its own workshop in the Smeaton Grange Industrial Estate, using its own in-house team. This means the same business is responsible for every stage of your project, which simplifies communication and accountability throughout.
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Related pages: double glazed doors. All made to measure in Smeaton Grange and installed by our own team.





