Insulating glass

What types of insulating glass are available?

There are several types of insulating glass, each offering its own level of thermal performance and unique characteristics:

• Double glazing – The basic form of insulating glass, consisting of two panes separated by an air gap.
• HR glass (High-Performance Glass) – An improved version of double glazing featuring a low-emissivity coating.
• HR+ glass – Includes an enhanced low-emissivity coating and insulating gas filling for improved thermal performance.
• HR++ glass – Double glazing filled with argon or krypton gas to significantly reduce heat loss.
• HR+++ glass (Triple glazing) – Three panes of glass with two gas-filled cavities, making it ideal for highly energy-efficient and passive homes.
• Vacuum insulating glass – Glass with an ultra-thin vacuum cavity that delivers the highest level of thermal insulation.

How does insulating glass work?

Insulating glass consists of two or more panes separated by a sealed cavity filled with an insulating gas such as argon or krypton. This construction reduces heat transfer, keeping warmth inside during the winter while helping your home stay cooler during the summer.

U-value and thermal performance

The U-value indicates how well glass insulates. The lower the U-value, the better the thermal performance.

HR++ glass is currently the most popular choice thanks to its excellent balance between performance and cost.

What is HR++ insulating glass?

HR++ glass is the most commonly chosen glazing solution for homes. It features a special low-emissivity coating that reflects radiant heat back into the building, while the cavity between the panes is filled with argon or krypton gas. As a result, HR++ glass provides significantly better insulation than standard double glazing, helping to reduce energy bills while creating a more comfortable indoor environment.

How is HR++ glass installed?

Replacing your existing glazing with HR++ glass involves several carefully executed steps:

• Removing the existing glass – The old glazing is professionally removed, including glazing beads and sealant where required.
• Inspecting the window frames – The glazing rebates are cleaned and repaired or adjusted if necessary.
• Installing the HR++ glass – The new glazing is fitted securely using glazing tape or specialist sealant to create an airtight installation.
• Finishing – New glazing beads are installed and the glass is sealed to ensure a perfect, weatherproof finish.

Which building elements should be considered?

When installing HR++ glass, several construction-related aspects should be taken into account:

• Window frames – Are your existing frames suitable for HR++ glass, or do they need replacing?
• Ventilation grilles – To maintain a healthy indoor environment, it may be advisable to install ventilation grilles together with the new glazing.
• Solar control & acoustic insulation – Additional glazing options, such as laminated glass, can further improve thermal and acoustic performance.
• Glazing beads and sealants – Proper sealing helps prevent heat loss and ensures an airtight installation.
• Façade protection – Protecting exterior walls against moisture helps maintain the insulating performance of your property.

Our specialists will be happy to advise you on the most suitable HR++ glazing solution for your home or commercial property.

Where can HR++ glass be installed?

HR++ glass is suitable for a wide range of applications:

• Homes & apartments – Ideal for both new-build and renovation projects.
• Commercial buildings – Offices and commercial properties benefit from lower energy costs.
• New-build developments – HR++ glass is a standard choice for energy-efficient homes.
• Renovation projects – Perfect for replacing outdated glazing while retaining existing frames where possible.
• Historic buildings – Special heritage glazing solutions with HR++ performance allow listed and historic buildings to become more energy efficient while preserving their original character.

The energy efficiency of HR++ insulating glass

HR++ glass offers significantly better thermal performance than standard double glazing and is one of the most cost-effective ways to reduce heat loss in your home. Thanks to its special low-emissivity coating and insulating gas filling, heat is retained indoors during the winter while helping to keep your home cooler in the summer.

How much difference does HR++ glass make?

A home fitted with HR++ glass can stay up to 5°C warmer during the winter and cooler for longer during the summer. This creates a more consistent indoor temperature without cold draughts or cold spots near windows.

How much heat is lost through single glazing?

Single glazing can account for up to 30% of the heat lost from a home through its windows. HR++ glass dramatically reduces this heat loss, resulting in noticeably lower energy bills.

Benefits of HR++ insulating glass

HR++ glass offers many advantages:

• Up to 30% less heat loss – Improves your home’s energy efficiency and delivers even greater savings when combined with cavity wall insulation.
• Lower energy bills – Reduced heating costs mean you’ll start saving money straight away.
• Improved indoor comfort – Eliminates draughts and helps maintain a stable indoor temperature.
• Noise reduction – Helps minimise unwanted noise from outside.
• Sustainable & environmentally friendly – Reduces your home’s CO₂ emissions by lowering energy consumption.
• Fast return on investment – HR++ glass typically pays for itself within just a few years.

Things to consider with HR++ insulating glass

Although HR++ glass offers many advantages, there are a few considerations:

• Not every window frame is suitable – In some cases, existing frames may need to be replaced.
• External condensation – Condensation on the outside of the glass is actually a sign that the glazing is insulating extremely well, although some homeowners may find it unexpected.
• The difference between HR++ and triple glazing – Triple glazing provides even better insulation but is heavier and more expensive.
• Additional ventilation may be required – Improved insulation often means ventilation should also be upgraded to maintain a healthy indoor climate.

With professional advice and proper preparation, you can choose the glazing solution that best suits your property.

Condensation on HR++ glass

Condensation can occur on HR++ glass in three different locations:

• Condensation on the inside
  This usually indicates that the humidity inside your home is too high. Possible causes include:
  • Insufficient ventilation – Opening windows regularly or installing ventilation grilles can help.
  • High indoor humidity – Activities such as cooking, showering and drying laundry increase moisture levels inside the home.
• Condensation on the outside
  This is a normal sign that the glass is performing well. Because the outer pane remains relatively cold, condensation may temporarily form during damp weather. It will disappear naturally as the outside temperature rises.
• Condensation between the panes
  If you notice mist or condensation between the glass panes, the sealed unit has failed. This means the insulating gas has escaped and the glazing has lost its insulating properties. In this case, the glass should be replaced.

Costs & grants for HR++ glass – Make the most of your investment

HR++ glass is one of the most worthwhile investments you can make to improve your home’s energy efficiency. The total cost depends on the type of glass, the size of your windows, the condition of your frames and the installation costs. In many cases, grants or financial incentives may also be available, making your investment even more attractive.

Grants for HR++ glass

Depending on your location, financial support may be available for installing HR++ glass, particularly when combined with additional energy-saving measures such as cavity wall or roof insulation.

How much funding could you receive?

The level of financial support varies depending on the applicable scheme and your specific project, helping to reduce the overall investment and shorten the payback period.

Typical eligibility requirements

• A minimum glazed surface area may apply.
• The glazing must meet specific thermal performance requirements.
• The installation should be carried out by a recognised insulation or glazing specialist.

BENG Vacuum Glass

BENG Vacuum Glass combines the exceptional insulation performance of triple glazing with the slim profile of single glazing. Thanks to innovative vacuum technology, it delivers outstanding thermal performance while measuring only 7.7 mm to 8.3 mm thick. This makes it particularly suitable for renovation and restoration projects where existing window frames need to be retained. The discreet spacers provide an almost invisible finish without compromising insulation or comfort. BENG Vacuum Glass offers an elegant, energy-efficient solution for both residential and commercial properties.

IsoPerform ScreenLine

IsoPerform ScreenLine combines the thermal performance of HR++ insulating glass with integrated Venetian blinds, giving you greater control over sunlight and privacy. Because the blinds are sealed between the panes of glass, they are fully protected against dust, dirt and damage. They are operated using a convenient magnetic slider. This innovative system not only adds a sleek appearance but also helps regulate indoor temperature and natural light, allowing you to enjoy maximum comfort without compromising the insulating performance of the glazing.

Invest in HR++ insulating glass with Pluimers

Pluimers supplies premium-quality HR++ glass with a U-value of 1.0, providing outstanding thermal insulation.

• Maximum energy savings – Up to six times better insulation than single glazing and three times better than standard double glazing.
• A comfortable indoor climate – Eliminates draughts and cold spots around windows while maintaining a pleasant indoor temperature.
• Environmentally friendly – Reduced heat loss means lower CO₂ emissions and a smaller environmental footprint.
• Excellent sound insulation – Helps reduce outside noise, making it ideal for homes in busy urban areas.
• Increased property value – Energy-efficient improvements such as HR++ glass make your home more attractive to future buyers.

Would you like to reduce your energy bills while improving the comfort of your home? Choose HR++ insulating glass from Pluimers. Our experienced specialists ensure a durable, airtight installation for maximum comfort and the highest possible energy efficiency.

Request your free, no-obligation consultation today »