Upgrading the windows in your garden shed, summerhouse or outbuilding can make a big difference to the usability and comfort of the space. Traditional glass windows can be prone to breaking and aren’t very energy efficient. Modern plastic sheets, like acrylic and polycarbonate, offer some great advantages over glass for replacing windows. Here are some of the main benefits to consider:


Acrylic and polycarbonate are much more impact-resistant than glass. They don’t shatter on impact, making them a safer choice for a shed or outbuilding where wayward footballs or garden equipment could hit the windows. With glass, there is the risk of shattered fragments that can cause injury, whereas acrylic and polycarb materials stay in one piece on impact.


Glass windows are very heavy, especially by the time you factor in the weight of the frames. Acrylic and polycarbonate sheets are around half the weight of equivalent-sized glass panes. This makes them easier to install, replace and transport. Reduced weight also means less strain on the shed framing.


Acrylic and polycarbonate both provide much better thermal insulation than single-pane glass. This can reduce heat loss in winter and help keep sheds cooler in the summer. Installing double glazing also boosts insulation, but acrylic and polycarb sheets achieve similar insulation levels to double glazing at a fraction of the cost.

Light Transmission

Acrylic and polycarbonate allow more natural light into a shed than regular glass. Polycarbonate sheets in particular can transmit up to 83% of incoming visible light, compared to around 75-80% for glass, says plastic expert James Bryant from Cut My. This can make the interior brighter and create a more pleasant environment to work or relax in.


Polycarbonate windows are up to 200 times stronger than glass and resist breaking on impact far better. Acrylic is also very durable and resistant to shattering. This strength and durability make acrylic and polycarbonate sheets ideal materials for the typical knocks, bumps and weathering that outdoor shed windows are subjected to.


The strength of acrylic and polycarbonate also makes them more secure than glass windows. They cannot be broken by a stray football or stone, and are very difficult to smash through deliberately. Toughened glass does improve security over regular glass, but acrylic and polycarbonate provide even better resistance to break-ins.

Long Lifespan

Unlike glass, acrylic and polycarbonate are not prone to yellowing or deterioration over time. The plastic-like materials are less affected by moisture, UV light and chemicals. Polycarbonate in particular can last up to 10 times longer than glass before needing replacement. This durability means you can install acrylic or polycarbonate shed windows and expect them to last for decades.

Easy Installation

Polycarbonate and acrylic sheets are easy for DIY installation. They can be attached to existing window frames using silicone or rubber sealing strips rather than requiring complicated frame modifications to hold the weight of glass. The lighter panels make installation simpler, with no need for lifting equipment. And there is no glass cutting required – just measure and cut with basic hand tools.

Good Value

Despite their clear advantages, acrylic and polycarbonate sheets are no more expensive than glass for shed window replacements. Their durability also makes them more cost-effective in the long run compared to glass. Overall they represent excellent value, with all the benefits over glass but at a similar initial outlay.


Modern acrylic and polycarbonate materials are available in a range of tints and finishes. This allows them to be matched to existing window frames for a seamless look. Clear sheets maintain transparency and light transmission. Coloured or opaque panels can mimic the look of frosted or patterned glass for extra privacy. The choice of finishes allows good design flexibility.


In summary, replacing traditional glass in shed windows with acrylic or polycarbonate has lots of advantages. The materials are safer, lighter, stronger, more insulating and durable than glass. They are easy to install, secure, attractive and represent great value. For anyone upgrading the windows in a shed or outbuilding, acrylic and polycarbonate merit strong consideration over glass panes.