Double & Triple Glazing

Double & Triple Glazing

Double glazing has been the standard for windows and doors for years now, but a huge number of properties across Gateshead, Newcastle, Durham and Northumberland are still fitted with single glazing, or early double glazing that's well past its useful thermal life. Upgrading to modern double glazing - or triple glazing where it makes sense - is one of the most straightforward improvements you can make to a property's comfort and running cost, and it's a job we do across houses, flats and conservatories throughout the North East.

This page is about the glazing itself - how it works, what the options are, and when triple glazing is genuinely worth the extra cost. For fitting new windows and doors around that glazing, see our new window installation and new door installation pages. If it's an existing sealed unit that's misted or failed, that's a repair job - see glass & sealed unit repairs.

What's Included

• Double glazed unit supply and installation
• Triple glazed unit supply and installation
• A-rated energy-efficient glass as standard
• Argon-filled sealed units for improved thermal performance
• Glazing fitted into new windows and doors, or as a like-for-like unit replacement
• Honest advice on whether double or triple glazing suits your property

How Double Glazing Actually Works

A double glazed unit is two panes of glass with a sealed gap between them, usually filled with argon gas rather than ordinary air, because argon conducts heat more slowly. That sealed gap is what does the insulating work - it's a far better barrier to heat loss than a single pane, which explains why single-glazed rooms feel cold near the window even when the heating's on. Modern double glazed units also use a Low-E (low emissivity) coating on one of the internal glass surfaces, an almost invisible metallic layer that reflects heat back into the room instead of letting it pass through the glass. Between the gas fill and the coating, a modern double glazed unit performs dramatically better than the double glazing that was standard even fifteen or twenty years ago - which is part of why some "double glazed" older properties still feel draughty despite technically having two panes of glass.

Triple Glazing: When It's Worth It

Triple glazing adds a third pane and a second sealed, gas-filled gap, pushing the thermal performance further again. The genuine question isn't whether triple glazing performs better - it does - but whether the improvement over good-quality modern double glazing is enough to justify the extra cost on your specific property. It tends to make the most difference on north-facing rooms that get little direct sun, properties on exposed or particularly cold sites, and homes where heating costs are a significant, ongoing concern. On a well-oriented, reasonably sheltered property already being fitted with modern A-rated double glazing, the jump to triple often isn't the most cost-effective place to spend the extra money. We'll give you a straight answer on your property rather than upselling triple glazing as a blanket recommendation.

Noise Reduction

Alongside thermal performance, glazing type makes a real difference to noise - a common concern for properties near main roads, in Newcastle and Gateshead's busier areas particularly. The sealed gap between panes acts as a sound barrier as well as a thermal one, and units built with panes of different thicknesses (rather than two matching panes) are particularly effective at cutting road noise, since it disrupts the way sound frequencies pass through evenly matched glass. If noise is a bigger concern for you than heat loss, it's worth mentioning at the survey stage so we can specify accordingly.

Signs Your Existing Glazing Needs Attention

• Condensation forming between the panes (not on the inside surface) - a sign the seal has failed
• A noticeable cold-glass draught even though the window closes and locks properly
• Visible fogging or a milky appearance to the glass that won't clean off
• Windows that are still single glazed, or an early double glazing system well past its expected lifespan

If it's specifically the sealed unit that's failed rather than the whole window, that's usually a repair rather than a full window replacement - see our glass & sealed unit repairs page.

U-Values and Energy Ratings Explained Simply

Glazing quotes often throw around terms like U-value and Window Energy Rating without explaining what they actually mean, so it's worth a plain explanation. U-value measures how much heat passes through the glass and frame - the lower the number, the better the insulation. A single pane of glass has a U-value of around 5.0; a decent modern double glazed unit comes in around 1.2 to 1.4; a good triple glazed unit can get below 0.8. Window Energy Rating (WER) takes that U-value and a few other factors and boils it down to a simple A to G letter grade, similar to the scale used on household appliances - A-rated is the top band, and it's what we fit as standard rather than an optional extra. When comparing quotes from different companies, it's worth asking directly what U-value and WER rating is being quoted, since "double glazed" alone doesn't tell you much about actual performance.

Condensation: Inside the Room vs Between the Panes

It's worth understanding the difference between the two, since they mean very different things. Condensation on the inside surface of the glass - the side facing into the room - is usually about humidity and ventilation in the property rather than a fault with the glazing itself, and is common in bathrooms, kitchens, and generally well-sealed modern homes with less natural airflow than older, draughtier housing. Condensation between the panes, on the other hand, is a clear sign the seal on that specific unit has failed and moist air has got into the gap - that's a repair job, not a ventilation issue, and it won't clear up on its own. If you're ever unsure which you're looking at, get in touch and we can usually tell from a description or a photo before booking a visit.

Glazing in Conservatories and Roofs

Glazing specification matters just as much - arguably more - in a conservatory roof, where a huge single-glazed or basic double-glazed polycarbonate panel can make a room unusable through summer heat and winter cold alike. Modern glazing options for conservatory roofs bring the same thermal benefits as they do in windows, and are a core part of the warm roof conversions covered on our conservatories & roofing page.

Safety Glass and Where It's Required

Building Regulations require toughened or laminated safety glass in certain locations - low-level glazing near floor level, glass in and around doors, and glazing in bathrooms among them - because standard glass in these positions poses a genuine injury risk if broken. This isn't an optional extra where it applies; it's a legal requirement, and it's built into the specification as standard on any glazing we fit in those positions without needing to be asked for separately.

Our Process

We start with a free, no-obligation survey, and depending on what you need, that might mean specifying glazing for brand-new windows or doors, or assessing whether existing units can be replaced on a like-for-like basis without touching the frames. You'll get a clear, itemised quote setting out exactly what's being fitted and why, and our own tradesmen carry out the installation.

Why Choose 1st Fix UPVC

Glazing specification is one of those details that's easy to skim over in a quote, but it's the single biggest factor in how a window or door actually performs day to day. We fit A-rated glazing as standard, not as an optional upgrade, and we'll explain clearly what's included rather than leaving you to work out the difference between suppliers' specifications yourself.

Areas We Cover

Double and triple glazing fitted across Newcastle, Gateshead, Durham and Northumberland. Call with your postcode to confirm coverage.

Frequently Asked Questions

Get a Free Quote

For double or triple glazing anywhere across Newcastle, Gateshead, Durham or Northumberland, call 0800 047 2610 for a free, no-obligation quote, or see our full range of services.