When architects, builders, or homeowners start comparing window options, one question comes up quickly: why does low emissivity glass cost more—and what actually drives that price?
Low emissivity glass (often shortened to Low-E glass) is widely recognised for improving thermal performance, reducing glare, protecting interiors, and cutting energy bills. But its cost can vary a lot from one project to another.
This guide breaks down the main factors that affect low emissivity glass pricing today, so you can understand where the money goes and how to specify smartly rather than overspend.
1. The Basics: What You’re Paying for with Low Emissivity Glass
Before diving into cost drivers, it helps to be clear on what low emissivity glass actually is.
Low emissivity glass is standard float glass with a microscopically thin metallic or metal-oxide coating that:
- Reflects long-wave infrared (heat) back toward its source
- Allows a high level of visible daylight to pass through
- Reduces UV transmission, helping to prevent fading of interiors
Compared with standard clear glass, Low-E glazing performs far better in:
- U-value (insulation)
- Solar Heat Gain Coefficient (SHGC)
- Interior comfort and surface temperature
If you’re still weighing up whether the performance difference is worth it, it’s worth reading
Is Low Emissivity Glass Superior to Standard Clear Glass?
Once you decide Low-E is the right direction, the next question becomes: what makes one Low-E specification more expensive than another?
2. Type of Low-E Coating: Passive vs Solar Control, Hard-Coat vs Soft-Coat
Passive vs Solar-Control Low-E
The functional type of coating has a direct impact on cost:
- Passive Low-E coatings
- Optimised to admit more solar heat while still reducing heat loss
- Often used in cold or heating-dominated climates
- Usually less complex than high-end solar-control stacks
- Solar-control Low-E coatings
- Designed to limit solar heat gain while admitting daylight
- Use more advanced layer stacks and tighter controls
- Tend to be more expensive per square metre, especially with very low SHGC and high visible light transmission
If you’re in a hot climate or dealing with large glazed areas, you may need a more sophisticated solar-control Low-E, which will push pricing higher—but can dramatically reduce cooling loads, as discussed in
How Does Low Emissivity Glass Help Control Heat in Hot Climates?
Hard-Coat vs Soft-Coat Manufacturing
Coating technology also matters:
- Hard-coat (pyrolytic) Low-E
- Applied while the glass is still hot on the float line
- Tough and durable, can be exposed or used in single glazing
- Generally less expensive, but with more modest performance
- Soft-coat (sputtered) Low-E
- Applied in a vacuum chamber after glass manufacture
- Achieves much lower emissivity and better spectral selectivity
- Requires protection inside an IGU, and costs more to produce
Higher-performance soft-coat solutions usually come at a premium, but they also deliver the most energy savings and comfort improvement.
For a deeper look at how Low-E compares to other glass treatments, including tint, see
What Makes Low Emissivity Glass Different from Tinted Glass?
3. Glazing Build-Up: Single, Double, Triple and Gas Fills
The glass unit configuration is one of the biggest drivers of price.
Single Glazing with Low-E
- Cheapest Low-E option, often using a hard-coat
- Limited performance compared with insulated glass units (IGUs)
- Typically used in budget-driven or retrofit projects where frames can’t accept IGUs
Double-Glazed IGUs with Low-E
- The most common configuration today
- Adds cost for:
- A second pane of glass
- Spacer system and sealants
- Possible argon or krypton gas fill
But compared to non-coated double glazing, Low-E IGUs can significantly reduce energy use and improve comfort. The performance gap (and why Low-E is worth the step up) is explored in
How Does Low Emissivity Glass Outperform Non-Coated Double Glazing?
Triple-Glazed IGUs with Multiple Low-E Layers
- Highest material and fabrication cost
- Often includes two or even three Low-E coatings, plus argon or krypton
- Best suited for:
- Extreme climates
- Ultra-low-energy or passive house projects
- Locations with strict performance codes
Because each additional pane and coating adds labour, handling risk and gas fill volume, triple glazing with advanced Low-E stacks is typically the top of the price ladder.
4. Performance Specification: How Ambitious Are the Targets?
Low-E products are available at a range of performance levels. As with most materials, pushing the envelope costs more.
Key spec drivers include:
- Target U-value – lower U-values usually require better coatings and sometimes thicker glass or triple glazing.
- Target SHGC – especially on sun-exposed façades; very low SHGC with high visible light often demands premium coatings.
- Visible Light Transmittance (VLT) – maintaining high VLT while reducing SHGC is technically challenging and often pricier.
In other words, the more you ask glass to behave like a precision filter rather than a simple barrier, the more you can expect to pay per square metre.
5. Size, Shape and Complexity of Units
Fabrication and handling risks show up in pricing:
- Large panes require:
- Heavier glass thicknesses for structural strength
- Specialist lifting equipment and more labour
- Greater risk of damage during transport and installation
- Non-standard shapes (raked heads, curves, cut-outs) increase:
- Cutting, edge-working and waste
- Lead times and production complexity
- Additional features such as laminated layers, acoustic interlayers or integral blinds add cost beyond the Low-E coating itself.
A simple, standard-size rectangular Low-E IGU will always be more cost-effective than an over-sized, shaped, laminated unit with multiple coatings.
6. Frame Systems and Integration
Glass doesn’t exist in isolation—frame choice affects unit design and price.
- Slim aluminium or steel frames may require:
- Higher-strength glass
- Careful detailing to control thermal bridging
- Thermally broken frames cost more upfront but support the performance of Low-E units
- Timber or composite frames can add fabrication and finishing costs, but may improve whole-window U-values
Sometimes a project pushes for large moving panels (multi-slide, lift-and-slide, folding doors). These require:
- Heavier hardware
- Stronger profiles
- Tight tolerances for IGU thickness and weight
All of that feeds back into the cost of the Low-E glass packages that fit into them.
7. Project Scale, Location and Logistics
The context of the project matters as much as the glass itself.
Scale and Repetition
- Larger projects with many identical units benefit from economies of scale.
- Small, one-off residential jobs often pay a higher per-unit price because set-up and handling costs are spread across fewer pieces.
Site Access and Installation Complexity
- High-rise or difficult-access sites require cranes, hoists or rope access.
- Remote or congested locations increase transport and on-site labour time.
In many quotes, you’ll see the glass cost combined with installation and logistics, so site constraints have a real impact on the apparent price of Low-E glazing.
Regional Supply and Market Conditions
Local factors can influence cost:
- Availability of coating lines and IGU manufacturers within a reasonable distance
- Currency fluctuations and transport costs for imported glass
- Local demand for high-performance glazing and regulatory pressure
In fast-growing and sustainability-driven urban areas, low emissivity glass is part of a broader toolkit for high-performance building skins, often alongside shading, green roofs and landscape strategies similar to those discussed in
Define Landscape Solutions in Smart Cities
8. Codes, Certifications and Warranty Requirements
As buildings aim for higher standards—LEED, BREEAM, Green Star, passive house, or local energy codes—the documentation and testing behind the glass become cost components too.
You may pay more for:
- Certified performance data and third-party test reports
- Extended warranties on seals and coatings
- Compliance with impact, fire or safety standards in specific jurisdictions
These added assurances often sit more heavily on commercial and institutional projects than on small residential jobs.
9. Incentives, Rebates and “Net” Cost
While they don’t change the sticker price of low emissivity glass, rebates and tax incentives affect what you pay in real terms.
In many regions, energy-efficient upgrades attract:
- Government grants
- Utility rebates
- Tax credits for high-performance windows and doors
When you combine those with:
- Lower ongoing heating and cooling costs
- Increased comfort and potential property value gains
…the effective cost of Low-E glazing over its life can be substantially lower than the initial quote suggests.
10. How to Control Costs Without Sacrificing Performance
If your goal is to get the benefits of low emissivity glass without blowing the budget, consider these strategies:
- Prioritise key orientations
- Use the highest-performance Low-E units on east, west and north/south (depending on hemisphere) sun-exposed façades.
- Use simpler Low-E or even standard double glazing in shaded or minor areas.
- Standardise sizes where possible
- Reduce the number of unique glass types and sizes.
- Avoid unnecessary shaping or complex cut-outs unless they’re critical to the design.
- Optimise performance, don’t chase extremes
- Ultra-low U-values and SHGCs cost more; aim for well-balanced specs that meet code and comfort needs without overshooting.
- Coordinate with shading and landscape
- Combine low emissivity glass with external shading, overhangs and landscaping to control solar gain.
- Smart design may allow you to use slightly less aggressive (and less expensive) Low-E coatings.
- Bundle work where possible
- Replacing multiple windows or completing an entire façade at once can secure better unit pricing and lower per-window installation costs.
Final Thoughts: Seeing Beyond the Square-Metre Rate
When you first see a quote for low emissivity glass, it’s tempting to focus purely on the per-square-metre number. But that price is the sum of many variables: coating type, glazing build-up, performance targets, unit complexity, frames, project scale and logistics.
Understanding what affects Low-E glass pricing across projects today helps you:
- Ask the right questions of suppliers and fabricators
- Avoid over-specifying in low-impact areas
- Invest more where performance and comfort gains are greatest
Most importantly, it lets you view low emissivity glass not just as a line item, but as a long-term asset—one that shapes comfort, energy use and sustainability for the life of the building.