What are the lead times for Glassworx products?

Lead times vary by brand. Internorm is typically 8–10 weeks, Dako is usually 6–8 weeks, and QFort (Cortizo) is generally 10–12 weeks. Lead times can change depending on factory workload, so for an accurate timescale it’s best to make an enquiry via our contact form.

Is triple glazing more expensive than double glazing?

Triple glazing is usually more expensive than double glazing, but many of our systems are designed for triple glazing, which helps keep the price difference relatively small. From time to time there are promotions such as triple glazing for the price of double. For current options, please contact Glassworx.

Can your windows and doors be used in a Passivhaus?

Yes. Glassworx offers several systems that are suitable for Passivhaus-standard projects. If you need detailed performance data and technical datasheets, the team can provide these on request – just get in touch via the contact page or email info@glassworxltd.co.uk.

Where is the Glassworx showroom located?

Our showroom is at The Cow Shed, Unit 4, Block 4, Manor Farm Business Park, Stirling, FK9 5QD. Visits are by appointment only, so please contact us in advance to arrange a time.

How much do Glassworx windows and doors cost?

All Glassworx products are bespoke, so pricing depends on sizes, specifications, glazing options and installation requirements. For an accurate quote, please complete our online enquiry form and the team will prepare a tailored estimate.

Do Glassworx work across the whole of the UK?

Yes, Glassworx supplies and installs across the UK. Delivery and installation costs may vary depending on the project location relative to our depot in Grangemouth, Scotland.

What are Glassworx payment terms?

For full installation (Gold Service), the usual payment terms are 50% deposit on order confirmation, 45% on confirmation of the installation date, and 5% seven days after installation. For supply only (Bronze) or installation support (Silver), the usual terms are 50% deposit on order and 50% on confirmation of the installation date. Full details are available in the Glassworx Terms and Conditions.

10 Installation Myths Every Homeowner Should Know

What homeowners really need to know before choosing windows, doors, and an installer.

When it comes to replacing or upgrading windows and doors, most homeowners focus on the product — triple glazing, frame materials, colours, U-values, and aesthetics. But there’s another factor that’s equally important:

👉 The installation.

At Glass Worx, we’ve seen firsthand how misconceptions about installation can lead to confusion, unrealistic expectations, and sometimes costly issues down the line. So today, we’re breaking down the most common myths about window and door installation — and revealing the truth behind them.

Myth 1: “New windows will automatically stop all draughts.”

The truth:
High-performance windows only perform as intended when they’re installed correctly. Even the best triple glazing in the world will struggle if the perimeter sealing is poor, the frame isn’t level, or air gaps are left behind.

Proper airtight installation = real performance.

Myth 2: “Any joiner can install premium or triple-glazed systems.”

The truth:
Modern systems — especially alu-clad, Internorm, Dako, Qfort, and Finstral products — require specialist installation methods, tools, and materials.

Incorrect installation can:

Damage the frame
Reduce airtightness
Increase heat loss
Impact warranties

Always choose installers trained in the specific system being fitted.

Myth 3: “Expanding foam is enough to seal a window.”

The truth:
Foam is one layer of insulation — not a complete seal.

A proper installation uses:

Compriband
Airtight internal tapes
External weather membranes
Correct perimeter insulation

This layered approach ensures long-term airtightness, thermal performance, and moisture management.

Myth 4: “Bigger windows mean more heat loss.”

The truth:
Modern triple glazing often performs better than older small double-glazed units.

Thanks to:

Low U-values
Thermally broken frames
Warm edge spacers
Multi-layer sealing

Large glazing can be just as efficient — and sometimes more efficient — than smaller windows.

Myth 5: “If the window fits the opening, the installation is correct.”

The truth:
Fit does not equal performance.

A correct installation must be:

Level
Plumb
Securely fixed
Fully insulated
Airtight inside
Weather-sealed outside

Anything less can lead to movement, draughts, leaks, and reduced energy performance.

Myth 6: “Triple glazing is too heavy and causes problems.”

The truth:
Triple glazing is heavier — but premium systems are engineered for this. With the right hinges, fixings, and install method, weight is not an issue. Problems only appear when the wrong system or incorrect installation is used.

Myth 7: “Condensation means the window is faulty.”

The truth:
Most condensation issues come from ventilation, not defective glazing. High-performance windows keep heat inside, meaning moisture often settles on the coldest surface — unless airflow is managed correctly.

Trickle vents, extractor fans, and good ventilation habits are essential.

Myth 8: “Homes shouldn’t be airtight — they need to breathe.”

The truth:
Buildings shouldn’t breathe. People should.

Airtight homes are warmer, quieter, and more efficient. Ventilation systems control fresh air properly — leaks do not.

Myth 9: “All window systems perform the same once installed.”

The truth:
Performance varies massively across brands and products. Frame materials, glazing packages, seals, and system engineering all affect efficiency.

Pairing a quality product with a quality installation is the key to long-term comfort and performance.

Why This Matters for Homeowners

Choosing windows and doors isn’t just about picking a style — it’s about protecting your home’s energy efficiency, comfort, and longevity.

At Glass Worx, we specialise in:
✔ Triple glazing
✔ Alu-clad systems
✔ High-end installations
✔ Premium brands including Internorm, Dako, Qfort & Finstral

We’re committed not just to supplying great products, but ensuring they are installed to the highest standard.