Can You Get Sunburnt Through Glass? Expert Insights

Many of us look forward to enjoying time outside in the warmer weather as the summer’s sunny days draw near. However, if we don’t take the necessary precautions, exposure to the sun’s ultraviolet (UV) rays can result in excruciating sunburns. When we’re outside, we’re frequently advised to wear sunscreen and protective clothes, but what about when we’re inside driving a car or seated next to a sunny window? Not all UV radiation is blocked from entering a room by glass windows. In this article, we’ll investigate if you can get sunburnt through glass that can still cause sunburns and explore the main variables influencing the amount of radiation that can pass through. 

Understanding UV Radiation

There are two primary types of ultraviolet radiation that come from sunlight: UVA and UVB. In comparison to UVB rays, UVA rays are less energetic and have longer wavelengths. Consequently, UVA rays reach further into the skin’s dermis layer beneath the epidermis. Long-term skin damage from UVA radiation includes sagging and wrinkles, as well as indirect DNA mutations that eventually lead to skin cancer. On the other hand, UVA rays do not instantly result in a sunburn. Conversely, UVB rays are more energetic and have shorter wavelengths. They only reach the skin’s outermost layer, the epidermis. Excessive exposure to UVB rays damages DNA directly and destroys epidermal cells, resulting in sunburn symptoms such as skin peeling, blistering, stinging, and reddening.

Glass naturally blocks most UV rays, in contrast to UVA rays. However, prolonged exposure to UV radiation behind glass can still cause sunburns and cell damage. Consequently, UVA exposure increases the risk of photoaging and cancer, while UVB exposure causes an acute inflammatory sunburn response. To prevent skin damage, we require protection against high levels of UVA and UVB radiation.

In essence, UVA and UVB both cause DNA damage to the skin, but UVB causes sunburn right away, while UVA causes long-term ageing effects. Glass totally blocks UVB rays, but UVA rays can still get through and cause burns over time.

What causes sunburn?

  • The main cause of sunburn is excessive sun exposure to UVB rays. UVB rays cause DNA damage to skin cells, which results in cell death and skin inflammation and redness.
  • UVA rays have the ability to pass through glass and penetrate deeper into the skin, damaging cells over time and indirectly causing DNA damage that can eventually result in cancer. However, unlike UVB, UVA does not instantly result in sunburn.
  • Since UVB rays cannot pass through glass, direct sunburn can only happen if exposure to UVB rays is prolonged and intense enough to cause indirect and cumulative damage that kills off skin cells.
  • The likelihood of getting sunburned through glass is dependent on various factors, including the glass’s thickness and tint, the duration and intensity of the exposure, and the individual’s skin sensitivity. 
  • Primarily UVB causes direct sunburn
  • UVA contributes to long term skin damage
  • Glass blocks most but not all UV rays
  • Sunburn through glass depends on exposure length/intensity and glass properties.

Can you get a suntan through glass?

Suntans are caused by exposure to ultraviolet (UV) radiation from the sun, just like sunburns. Most UVB rays that cause sunburn are blocked by glass, but UVA rays that cause tanning can still get through.

Nonetheless, in comparison to exposure to the sun, less UVA radiation passes through glass. As a result, the depth of tan that develops behind glass will likely be lighter and take longer than in direct sunlight.

  • Several factors determine how much tan you get through glass, including:
  • The length of exposure: greater exposure results in increased UVA penetration of glass over time.
  • The intensity of the sun’s rays: brighter days release more UVA into indoor spaces
  • Fair skin types tan more slowly than darker skin types
  • Tinting glass: Dark or UV-blocking glass reduces the amount of UVA radiation
  • Glass thickness: Windows with thicker glass block more light.

In conclusion, long-term, repeated exposure to the moderate UVA levels that penetrate glass can result in light tans, especially in people with olive or darker skin tones. However, the tan takes far longer to develop than it would in direct sunlight. Wearing the right sunscreen is still necessary if you spend a lot of time near windows that let in the sun.

How To Protect Yourself from UV Radiation Indoors?

  1. Use sun-protective window films: To prevent up to 99% of UV rays, think about installing reflective or UV-filtering window films or laminates.
  2. Close the curtains and blinds: To provide an additional UV protection layer, draw back drapes, blinds, or shades during the hottest parts of the day.
  3. Move away from windows: Distance causes the UV rays to become less intense. When at all possible, keep as far away from windows as you can.
  4. Use a sunscreen inside: Before spending an extended amount of time in direct sunlight through windows, apply broad spectrum SPF 30+ sunscreen. Apply again every two hours.
  5. Put On Sun Protection Apparel: When spending time near windows, cover up with tightly woven long sleeves, trousers and collared shirts.


Glass windows do not completely block UV rays that cause sunburns, even though they do block a portion of the sun’s harmful UV radiation. Particularly UVA rays can still pass through glass and over time, with prolonged exposure, harm DNA in the skin. No matter where we are, we need to be mindful of safe sun habits like seeking out shade, putting on UV-blocking window films, using protective clothes close to windows, and applying broad-spectrum sunscreen indoors. It will be easier for us to enjoy the sunny weather without getting burned if we are aware of the skin risks associated with indoor UV exposure. 


  1. Does Window Tint Prevent Sunburn?

Yes, UV-blocking window tints can prevent sunburns by filtering out up to 99% of ultraviolet radiation.

  1. Can UV rays penetrate all types of glass?

No, some glass with special coatings can block most UV rays, but plain glass allows a significant amount through.

  1. Is it necessary to wear sunscreen indoors?

Yes, you need sunscreen when spending extended periods of time near sunny, untinted windows.

  1. Do car windows provide UV protection?

Typically car windows block UVB but a variable portion of UVA penetrates through side windows, requiring skin protection.

Enquiries Book An Appointment Get In Touch Virtual Tour