July 3, 2026

03 Jul 2026

FAQs: Does Putting Tin Foil on Windows Keep Heat Out?

One viral hack that’s currently doing the rounds is putting tinfoil on windows to keep the heat out. We can definitely see the appeal – it’s cheap, easy to access, and when it’s sweltering inside most of us will give anything a go to bring the temperature down a few degrees. So, does putting foil on your windows really work, or is there a better window hack?

How foil works to block out heat

The thinking behind this hack is that foil is reflective, so can ward off incoming rays. As sunlight contains invisible infrared radiation (heat), when this hits standard glass windows it passes straight through them. The heat then gets trapped inside the room, warming it up.

However, because of the reflective properties of the foil, as well as its low emissivity – aluminium can reflect a significant amount of radiant heat – it can bounce the infrared rays away from the window, minimising the amount of heat that can get inside a building.

Does foil on windows actually work to keep a room cool?

Anecdotally, some people do find that it can drop the temperature by a few degrees. However, one key mistake is putting foil on the inside of the window, which we’ve seen a lot of people doing. Putting it on the inside of a window can trap solar heat, which can create extreme thermal stress between the glass and the foil. As this will heat up the glass unevenly across the window pane, the risk of the glass breaking is significantly higher.

Double or triple-glazed windows are at particular risk, as it can cause the internal pane to expand and potentially even shatter. Sticking foil to the outside of a window can prevent this from happening, and in a pinch might make a hot day indoors feel a bit easier.

What can be used instead of aluminum foil on a window?

Foil may offer some temporary relief, but it’s not an ideal solution in the long run – especially not for commercial properties. For properties with a lot of windows, or windows above ground floor level where applying foil to the outside can be risky, using foil won’t be as effective. Plus, foil-covered windows make a room much darker, and for a business especially, don’t give off the most professional appearance. Blackout blinds or curtains can offer similar properties, but again, come at the expense of natural light.

For a long-term solution, we would recommend solar control window film. Sometimes referred to as heat rejection window film, it is designed to better regulate the transmission of heat and light through glass windows.

Solar control film is a lightweight film that comprises layers of polyester that reflect and absorb certain wavelengths of sunlight before it has a chance to penetrate the glass. This means that excess heat is kept out of the property, keeping the temperature more stable. One of the major benefits of solar window film is that you can still see through them, and they don’t block out natural light.

It’s a simple and effective way to regulate the temperature inside a commercial property. Naturally, it costs more than a roll of tin foil, but many people find that it can save them money on energy costs as they have less need to rely on expensive cooling systems. In the winter, the film has the opposite effect – it can conserve heat to keep it cosier, reducing the need for central heating. With more hot summers on the horizon, solar film makes an excellent long-term investment for commercial properties that want to make working conditions more comfortable for employees.

29 Jun 2026

Strengthening the Security of Your Windows

Windows are the weakest point of a building, as they are more susceptible to damage and breakage. Smash-and-grab burglaries by opportunistic thieves aren’t uncommon, and the threat of attacks – whilst uncommon – is something to be considered. A broken window is easy for intruders to force through and gain access to a building, so finding ways to improve the security of your commercial property is key.

We have outlined some of the most common ways to upgrade the safety of your windows.

Lockable windows

If you’re getting new windows fitted – especially if they are at ground level – go for lockable ones. The most secure lockable models come with key operated, multi-point locking systems. Most modern windows can only be opened with a key to turn the handle, which can help to prevent intruders from forcing it open.

Locks can also be retrofitted to existing windows, using tools like sash jammers – which can be attached to the window frame to physically stop the window sash from opening inwards – or window restrictors, which are connected between the window frame and sash to limit how far it can open.

Security bars

Security bars are sturdy metal barriers – usually steel or cast iron – that can be attached to either the inside or outside of windows. Also referred to as ‘burglar bars’, they act in part as a visual deterrent, as they signal to would-be thieves that they are dealing with a well-secured property. They also make it very difficult for them to pry open the windows.

However, a major downside of security bars is that they can be a safety hazard for building occupants. Having fixed bars means that in the event of an emergency, like a fire, they block potential escape routes. Additionally, they reduce the amount of natural light that gets in and obscure the view. And, let’s face it – they don’t exactly make a property look welcoming!

Roll down shutters

Similarly, roll down security shutters are sturdy metal blinds that can be attached to the outside of windows and pulled down when the property is vacant. Shutters make an excellent deterrent because they are a physical barrier to entry. Usually made of steel or aluminium, they make it very difficult to break through, which also means they act as a visual deterrent for opportunistic intruders. However, shutters only add protection when the property is vacant, such as at night, which can leave windows vulnerable during the day.

Alarm systems

There are a range of window alarms on the market, including magnetic contact sensors that trigger an alarm when a window is opened, and vibration sensors, which are triggered when the glass is struck. Window alarms can range from small, budget-friendly battery powered devices, to smart ecosystems that you can monitor from your phone. Although they don’t reinforce a window or add any physical protection, they can be great to have in tandem with other physical security measures.

Security window film

Security window film is a lightweight polyester film that is applied directly to existing glass to reinforce it, making it more durable and resistant to breakage. In the event of impact, the film holds the shards of glass together to prevent injury. Because the glass is held together in the frame, it also makes it much harder for would-be burglars to get inside the property, as it doesn’t give them an easy access point.

It’s not just effective against break ins – security window film can also provide shatter resistance in the event of accidents, natural disasters or even bomb blasts, which is of a particular priority for high-profile businesses, or those with a large public presence, such as government buildings.

Safety window film adds extra protection to a window without sacrificing natural light or visibility, and it is quick and easy to apply.

Upgrade the security of your windows with OVAGLAS

OVAGLAS provides a range of security window films that can be applied to existing glass, reducing the need for expensive new glazing. Our security films are designed to withstand impact, protect against accidental damage, and prevent potential dangers caused by shards of broken glass.

If you have any questions about our security window films – or any of our other products – get in touch with our team and we’ll be happy to help.

29 May 2026

Reducing Heat Gain Through Windows

As much as we all love a gloriously sunny day, it does lose its appeal when you’re stuck inside a hot workplace all day. A surprising amount of commercial properties just aren’t cut out to handle heat, quickly turning into something akin to a sauna – not ideal when you’re trying to get through a day’s work.

If every hot day in the workplace you find yourself searching to find if there’s a maximum legal workplace temperature, it might be time to do something about it.

Why do windows let in so much heat?

A significant amount of heat gain can be attributed to windows, mostly because they let in so much sunlight, particularly infrared radiation. Even a well-insulated window struggles to block out much solar energy, so when it’s sunny outside, it heats up the interior surfaces in a room, which will also then radiate heat and contribute to warming the space. Much like a greenhouse, glass windows will keep the heat trapped inside.

Double-glazed windows are far better at insulating a property, as they have an air or gas pocket between the panes that helps to reduce the movement of heat. However, they can’t stop solar radiation from getting inside your property, so some heat transfer can still be expected.

How to reduce heat transfer via windows

Curtains or blinds

Curtains or blinds can be very handy at blocking light, particularly blackout curtains or blinds. Blackout curtains and blinds are made from thick, dense fabric that can block out the majority of natural light. Some also come with thermal lining to further help keep a room cool. Remember that curtains and blinds will need to be drawn well before the sun is at its peak – usually around midday, but it can still be very warm outside before this – to make sure enough heat is being blocked.

Keeping blinds and curtains drawn can also help to reduce glare, which can cause eye strain and take a hit on productivity – and it’s an easy solution, as if you already have curtains and blinds fitted, it takes a matter of seconds to close them.

Of course, the major downside to curtains and blinds is that you end up blocking out most – if not all – of the sunlight! Bright days can be few and far between, so working in a dark room when the sun is shining outside isn’t ideal. They can also reduce airflow in a room, meaning that heat stays trapped, making the room feel stuffier.

Double-glazed windows

If the windows in your building are single glazed, they will let in a lot more sunlight than double-glazed windows, which can make the room feel uncomfortably hot. They also don’t have as much UV protection as double-glazed windows, which can lead to furniture fading or even skin damage.

Double-glazed windows are a more energy efficient option, as the gap between the two panes acts as insulation, which reduces heat transfer. During the summer, this allows less sunlight to come through the windows, which helps to keep the indoor temperature more comfortable. Over time, this will help save money from cooling costs – such as fans or air conditioning – as well as heating costs in winter, as it can also work to stop the heat escaping.

Although double-glazed windows can be a great long-term investment, they definitely aren’t a quick fix – if there’s a sudden heatwave forecast, getting new windows fitted is not the answer! It can also be very expensive to replace your windows, especially in a large building.

Low-E glass

Low-E glass – also known as low-emissivity glass – is a type of glass that has a microscopic, clear coating that helps to reduce thermal transfer. Low-E glass can be beneficial in both summer and winter, as in summer it helps to keep heat out, whilst in winter it retains the warmth.

The coating on Low-E glass is made of metallic oxide, meaning that it deflects sunlight – including harmful infrared and UV rays – back outside, whilst still letting in plenty of natural light. Similarly to double-glazing, Low-E windows keep energy costs down by reducing the need for you to use heating or cooling systems.

However, the downside to Low-E glass is also the same as double-glazing – it’s not a quick solution, and the treated glass can be significantly more expensive than regular glass. As a long-term investment it can be hugely beneficial for your business, but there is a significant initial cost.

Solar screens

Solar screens are lightweight panels made of mesh that are usually custom-designed to the size of your windows to fit neatly over them. The mesh is usually made from polyester or fibreglass that is coated with a UV-resistant material, which can help to filter out solar radiation.

They are typically fitted on the outside of the window to stop the sun from directly reaching the glass, which is where the majority of solar gain tends to occur. This means that less heat is absorbed by the glass windows, therefore less heat is passed into the room, keeping it a more comfortable temperature.

Solar screens do still let some natural light through, due to them being made of mesh, although it will be duller than with a clear window. Another downside of solar panels is that they aren’t suitable for all window orientations, as some windows don’t receive as much sunlight, so a solar panel might end up blocking out the light unnecessarily.

Solar window films

Solar window film – also known as solar control window film – is a thin, durable film that is applied to windows to help reduce heat transfer, filter out UV rays and minimise glare.

Solar film has a reflective quality which allows it to reflect a certain amount of the sun’s rays before it reaches the glass, and also absorbs some of the solar heat to prevent it from getting inside the building. It won’t stop natural light from getting in, but it will mean that the temperature inside stays far more stable.

Many types of solar film block out a high percentage of UV rays, which can fade interiors and furnishings, and helps to reduce glare for improved visibility. As window films can block a pretty significant amount of heat, it means there is less need to be reliant on air conditioning, which can help your business save some money. Similarly, in winter, window film works as insulation to better retain heat.

Window films are an unobtrusive option, as they simply adhere to your existing windows, and can be installed quickly and easily. Although you can apply window film yourself, it’s definitely better to leave it to the professionals!

Solar gain protection from window film

As window film specialists, we offer a simple and cost-effective way to minimise excess solar heat gain and glare, leading to a more comfortable working environment – not to mention reducing your energy costs!

With summer rapidly approaching, there’s no better time to upgrade your windows – get in touch with the OVAGLAS team.

27 May 2026

Energy Saving Window Film

Optimise your glazing with high-performance coatings. Energy saving window film is a simple and effective solution for businesses looking to improve the energy efficiency of a commercial property, but without sacrificing natural light.

Window film is applied to your existing windows, providing a cost-effective solution that can significantly benefit your workplace, from maintaining a more comfortable indoor temperature to saving money on energy bills.

OVAGLAS also offers Clarifoil® Anti-Fog Film for Freezer Doors, a high-performing anti-fog film for commercial freezers.

Solar Control Window Films

Solar control window film offers can be installed on existing windows to reduce or eliminate common problems like excess heat, glare and faded furniture. It blocks out potentially harmful UV rays whilst still letting in natural light and warmth, and without obstructing your view.

Solar window film works by reflecting or absorbing certain wavelengths of sunlight before it has the chance to penetrate the glass. It allows visible light to pass through, but unwanted wavelengths like UV are rejected. In cooler months, window film works to conserve warmth, as a significant amount of heat is lost through windows, meaning that it brings benefits all year round.

Clarifoil® Anti-Fog Film For Freezer Doors

We also offer Clarifoil® Anti-Fog Film for Freezer Doors, an anti-fog film for retail freezers that prevents the doors from fogging when opened by customers. It maintains glass transparency so that the merchandise inside can clearly be seen, which improves the customer experience – not to mention the savings on energy consumption and your electricity bill.

Energy Saving Window Film FAQs

Does solar window film work?

Solar window film is very effective at preventing significant amounts of sun-generated heat from passing through windows. As soon as it’s applied, solar window film helps to stop excess heat passing through, and filters out UV rays – as well as being damaging to the skin, UV is one of main contributors to fading upholstery and furnishings. In winter, solar control film adds an extra layer of insulation, preventing heat transfer between the indoors and outdoors.

Window film is ideal for workplace windows, as it can reduce irritating glare from solar heat that reflects off computer screens and makes them hard to see.

Is window film energy efficient?

Solar window film is very energy efficient all year round. In commercial premises, using window film can lead to significant cost savings in the summer months, as the building will be less reliant on air conditioning to keep it cool. When it’s colder, window film helps to retain heat, which will help to save on heating bills.

Is window film better than blinds?

Curtains and blinds can be effective at blocking sunlight when they are closed, but it does block the view and stop natural light coming in. They also don’t stop heat from entering through the windows, as they are set back from the glass. Meanwhile, window film stops excess heat from coming in, without reducing the amount of visible light or obstructing your view.

Energy saving window film is also far easier to maintain and clean than curtains or blinds. Solar control window films also offer UV fade protection and glare reduction.

Is window film easy to maintain?

Window film is easy to maintain and keep clean, especially compared to curtains and blinds. It can be cleaned using a mild detergent solution and a soft cloth – just take care to avoid using any abrasive or harsh products that could cause scratches.

How to install solar film on windows

Although it’s possible to install window film yourself, it’s best left to the professionals. Improper glass cleaning, using the wrong tools, or errors in application can all compromise the effectiveness and durability of your window film. Having it installed correctly means that you will be able to reap the benefits of your window film. OVAGLAS offers on-site surveys to ensure you are choosing the right window film for your commercial premises, and our experienced team will fit it to the highest standard.

22 Apr 2026

How Window Film and Flexible Anchoring Reduce Blast-Related Glass Hazards

Despite the fact that glazing tends to be the weakest point in a building, it’s often overlooked as a security risk. This means that windows are particularly susceptible to bomb blasts, break-ins and attacks, as they are fragile and can shatter very easily. A broken window is easy for intruders to force through and gain access to a building.

As well as being relatively easy to break, glass can be incredibly dangerous in the event of an attack. The force of a bomb blast or explosion can cause glass to shatter into numerous shards, which act like projectiles that can cause devastating injuries, so finding ways to strengthen windows can significantly reduce this risk.

What safety and security window film does

Safety and security window film is designed to hold shards of glass together in the event of an attack. It’s a thick, durable film that can absorb energy from an impact to reduce the chances of injury. Flying glass shards are a significant cause of injuries as a result of bombings and explosions, so safety film was created to keep broken glass in the frame. Because it holds the glass together and doesn’t create gaps in the frame, it also doesn’t give an easy access point for would-be intruders.

It doesn’t stop the glass from breaking during impact, but it creates an extra layer of security by holding the pieces together, making forced entry more difficult, and strengthening your glass windows against impact.

Why anchoring matters as well as film

Whilst safety window film can significantly improve the security of a building, film alone doesn’t prevent the glass pulling away from the frame. An anchoring system is used in conjunction with window film to secure a window directly to the structure of the building itself, keeping it firmly in place. Anchoring makes a window film more stable against impact, adding an extra level of security.

How OVAGLAS® Flexible Anchoring System works

The OVAGLAS® Flexible Anchoring enhances the performance of safety and security window films in the event of an explosion. They secure the filmed glass to the frame, creating a continuous connection between the glass, window film and the frame. Using an anchoring system allows a window to better absorb shock, rather than failing under pressure from an impact. The OVAGLAS® system has a FlexZone, which is an energy-absorbing design to allow for this.

Just like security window film, the anchoring system can be retrofitted into existing buildings, which is significantly less disruptive than installing new windows.

Testing, certification and what buyers should look for

The security and safety of your building should be a high priority, so checking that a window system has been thoroughly tested and complies with safety standards is key. Although laboratory testing can give a good idea of how a window film or anchoring system could work under impact, it’s better if there is evidence of real-world testing to see how it holds up.

There are recognised safety standards that products should comply with, like ISO or EN, as this is evidence that the products have been tested and are legally compliant, so you can be assured that they can be trusted. Our anchoring system has been tested to European and international standards, including ISO 16933 EXV25.

Additionally, you should feel confident that the installer of the film or anchoring system is accredited, as if they are fitted by someone without the relevant knowledge or experience, you can’t be certain that the film will be up to scratch.

Typical applications for safety window film

All venues and building types can benefit from safety window film, as it’s a simple, effective and durable way to improve the safety of a property. It can be used in:

Venues – No matter the size of the venue, window film can add extra security and help to protect crowds
Transport hubs – A more common target for terrorist attacks as there is high footfall
Retail premises – Shops can be targeted by thieves, so window film can help to prevent this
Government buildings – Also a potential target of attacks and threats
Commercial offices

If your property has any valuables on site, carries sensitive data, or is frequently busy, it might be more at risk of attacks.

How this fits into wider protective security planning

There are a lot of factors to consider when you’re planning how to improve the security of your property. From training your staff on safety procedures to controlling access to your building, taking a multi-layered approach to security means that more bases will be covered. This is especially important with the new regulations that will be coming into force under Martyn’s Law, which was passed in 2025 to improve protective security and preparation by requiring public venues and events to implement measures against terrorism.

Using window film and anchoring systems can reduce the risk of injury caused by flying glass in the event of attacks, or can help to buy time in which to react or call authorities during forced entries. It’s an incredibly straightforward way of upgrading the safety of your existing windows, and comes with little downtime, so it’s an excellent way of further bolstering the security of your property.

Speak to OVAGLAS about assessing glazing risk in your building

As part of your practical preparation for Martyn’s Law, reviewing the glazing risk in your building can be an excellent precautionary measure. To find out more about how window film can add extra security to your commercial property, get in touch with the OVAGLAS team.

21 Apr 2026

What Martyn’s Law Means for Venues and Public-Facing Businesses

Martyn’s Law – officially called the Terrorism (Protection of Premises) Act 2025 – is a new piece of legislation that was created to strengthen safety protocols in public venues and events.

The new law is named after Martyn Hett, who was tragically killed in the Manchester Arena attack in 2017. His mother, Figen Murray, campaigned tirelessly for the introduction of the new law, which was created to strengthen security at public premises and events. It will establish a minimum legal standard of security at venues and events that host more than 200 people.

Martyn’s Law means that venues need to take proactive steps to ensure the safety of occupants and visitors and reduce the risk of physical harm. Although the law was passed on 3 April 2025, it won’t come into effect until at least 24 months from this date, giving venues plenty of time to prepare.

The difference between standard tier and enhanced tier

The kinds of measures that venues need to implement depends on the tier that the new law assigns them. There are two tiers: Standard and Enhanced.

Premises and events that fall under the Standard tier are those that host between 200-799 people at the same time. There will need to be a named responsible person for each premises, who needs to notify the Security Industry Authority (SIA). This person will be responsible for ensuring that appropriate security measures are in place, including procedures for:

Evacuation – getting people out of the building safely
Invacuation – bringing people into the premises if necessary
Lockdown – securing the premises to restrict or prevent an attacker gaining access
Communication – alerting people of danger

This tier is more about introducing more stringent safety procedures and training staff to make sure that everyone knows how to react in the event of an emergency.

If your premises has a capacity of 800 or more, it will fall under the Enhanced tier. Venues of this type will also need a responsible person to notify the SIA, and will also need to implement the security measures listed above. However, Enhanced premises also need to consider public protection measures that will mitigate risk of harm and offer greater public protection. These measures are in relation to:

Monitoring the premises/event and the immediate vicinity
Controlling the movement of people around the premises
Physical safety and security of the premises/event
Security of information that might assist in the planning or execution of terrorism

These measures can be implemented through training people, introducing new processes, or carrying out physical security measures.

Why physical security enters the discussion for larger premises

Martyn’s Law focuses on proactive security measures by identifying potential weaknesses in how venues operate, rather than reacting after an incident has occurred.

Large venues concentrate hundreds or even thousands of people in a confined area, which can make them a significant target for terrorist attacks. Introducing more stringent physical security measures, such as thorough bag checks and CCTV systems, can act as a deterrent, as would-be attackers are more likely to be caught before they gain access. Having physical security measures can act as a deterrent.

In the event of an attack, a venue will need to be able to respond quickly and effectively. In a bigger venue, this can be harder to control, as there are more people across the building. Having physical safety features like clear evacuation routes and barriers can help a crowd move through the venue more efficiently and safely.

The actual building itself can also play a role in the safety of larger venues. Physical protective measures like reinforced windows and doors, barriers around the perimeter of the venue and access control systems can be used to delay or prevent forced entry, and make the venue safer for occupants in the event of an attack.

Why glazing deserves more attention in security reviews

Glazing is often overlooked during security reviews, despite the fact that it tends to be the weakest point in a building. This means that it is particularly susceptible to bomb blasts, break-ins and attacks, as it is fragile and shatters easily. A broken window is easy for intruders to force through and gain access to a building.

As well as being relatively easy to break, glass can be incredibly dangerous in the event of an attack. The force of a bomb blast or explosion can cause glass to shatter into numerous shards, which act like projectiles that can cause significant injury. Injuries from broken glass are extremely common in attacks, so considering ways to strengthen glazing can significantly reduce this risk.

What blast protection window film and anchoring systems are designed to do

Blast protection window film is designed to withstand impact and protect against damage. In the event of an attack, window film will keep the shards of glass safely in the window frame. Because it holds the glass shards together, it doesn’t create a gap in the window where attackers can easily gain access, which also gives staff more time to react and call the emergency services.

Anchoring systems are a unique type of glass containment system, which can be used in conjunction with blast protection film for added security. It further strengthens a window by holding the glass in place if it gets broken – in fact, it has achieved the highest performance rating of any glazing retention system in the world.

Questions venue and estates teams should ask now

It’s important for venue and estate teams to start planning for Martyn’s Law as soon as possible, to make sure that your staff are fully trained and that your building is protected. As you start preparing, you should be asking:

What are the most likely scenarios that we should be planning for?
Have we carried out a thorough risk assessment of the building?
How secure is our venue currently against forced entry?
Are there vulnerable areas of the building that need reinforcing?
Is there comprehensive CCTV in the building, and it is monitored regularly?
Are there clear evacuation routes?
Do staff know their responsibilities in the event of an emergency?
Do we know how to communicate with each other and visitors in an emergency?
Who is going to be responsible for decision making?
Which level of Martyn’s Law applies to our building?

Having a comprehensive plan in place makes sure that you are adhering to the upcoming legislation, but also means that if the worst does happen, your venue is prepared to react appropriately to keep people safe.

FAQs: Does Putting Tin Foil on Windows Keep Heat Out?

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FAQs: Does Putting Tin Foil on Windows Keep Heat Out?

How foil works to block out heat

Does foil on windows actually work to keep a room cool?

What can be used instead of aluminum foil on a window?

Strengthening the Security of Your Windows

Lockable windows

Security bars

Roll down shutters

Alarm systems

Security window film

Upgrade the security of your windows with OVAGLAS

Reducing Heat Gain Through Windows

Why do windows let in so much heat?

How to reduce heat transfer via windows

Curtains or blinds

Double-glazed windows

Low-E glass

Solar screens

Solar window films

Solar gain protection from window film

Energy Saving Window Film

Solar Control Window Films

Clarifoil® Anti-Fog Film For Freezer Doors

Energy Saving Window Film FAQs

Does solar window film work?

Is window film energy efficient?

Is window film better than blinds?

Is window film easy to maintain?

How to install solar film on windows

How Window Film and Flexible Anchoring Reduce Blast-Related Glass Hazards

What safety and security window film does

Why anchoring matters as well as film

How OVAGLAS® Flexible Anchoring System works

Testing, certification and what buyers should look for

Typical applications for safety window film

How this fits into wider protective security planning

Speak to OVAGLAS about assessing glazing risk in your building

What Martyn’s Law Means for Venues and Public-Facing Businesses

The difference between standard tier and enhanced tier

Why physical security enters the discussion for larger premises

Why glazing deserves more attention in security reviews

What blast protection window film and anchoring systems are designed to do

Questions venue and estates teams should ask now

Speak to OVAGLAS about assessing glazing risk in your building

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