How thick should skylight glass be?

August 4, 2023

When determining the thickness of skylight glass it is worth noting that skylight glass is most commonly used for insulation ranges between 4mm and 6mm in thickness. It must be added, however, that it depends on how big the skylight is and the type of glass you are wanting to install. With that in mind, there are a few things to consider before determining your skylight glass needs.

How safe is skylight glass?

Skylights are designed to be safe, sturdy, and durable. Designed with clear toughened safety glass, you are guaranteed thermally insulated skylights that can withstand tough conditions such as bad weather and strong impact. Made to withstand powerful UV rays, you can rest assured that your skylight roof can maintain perfect condition throughout any type of weather, whilst providing your home with beautiful natural lighting. Before any skylights are installed or added to the market, rigorous testing is carried out to ensure each product is safe and produced with high quality.

Are skylight roofs secure?

Skylight roofs are designed to be secure and thick enough to prevent leakage and burglary attempts. With easy installation and toughened glass structures, you can lay your worries aside for any security risks with your skylight roof structure. Each installation is required to meet standard security risk factors, with the option for additional security measures if you are unsure of the process. 

Building Codes and Standards in Determining Skylight Glass Thickness

Building regulations must be approved before fitting a skylight to determine the safety and security requirements for the installation. The thickness of glass installed for skylight purposes commonly ranges between 4-6mm with a high-quality polished edge finish. 

When determining standards for skylight glass installation, areas such as heat loss, safety and security, glazing types and framing systems must be considered. Glass which is installed to walk upon must be sturdy enough to withstand weight and pressure applied. Non-fragile glass is the standard risk assessment when determining the thickness of skylight glass roofs to ensure the safety of the structure.

Risk factors considered in glass building codes focus on its breakability, fire resistance, natural light production and its ability to withhold heavy impact. All of these areas should be determined when choosing the thickness of a skylight for each individual building’s needs.

Tuffx skylights are designed with 6mm toughened safety glass with 1.2 w/m2 U-Value for extra security and protection.

Different glass types and their impact on skylight thickness

Laminated glass and toughened glass are both commonly used for skylight fixtures. 

Toughened glass provides five times extra strength and durability against outside forces, which is why it is commonly used for the outside pane to reduce pressure from harsh weather and man-made forces. Toughened glass is typically reduced in thickness compared to laminated glass, allowing more natural lighting into the interior of your home.

Laminated glass is commonly chosen with safety and security in mind as the glass pane is designed to crack rather than shatter and fall, reducing the risk of sharp glass fragments falling from the skylight. PVB laminated glass uses two or more sheets of glass, alongside one or more layers of polyvinyl butyral creating a thicker panel for skylight fixtures. Resin laminated glass contains two sheets of glass and one layer of liquid resin slightly reducing the size in thickness compared to PVB. 

Impact glass is also used for skylight roof fittings as impact glass is created using multiple layers of laminated glass to create a sturdy structure designed to withstand harsh weather such as strong hail, wind, and hurricanes. However, impact glass is less commonly used than toughened or laminated as the prior offer more durability and strength.

Matching Glass Thickness to Structural Needs

In terms of skylight thickness, fixed and opening roof lights should be around 6mm in thickness to assure it is thick and durable enough to not shatter. However, The thicker the glass installation is, the less light will be able to come through.

Toughened glass is more commonly used for structural glazing systems as its strength is made to withstand most of the weight within a structure. This can be used when the glass is fully framed or two-edged framed. Therefore, if you’re looking to create a large glass installation within your home, toughened glass is the perfect fit for you. The average of 4-6mm in glass thickness tends to only be installed up to 1000mm in width, which most conservatory and roof installations adhere to.

For walk-on floor glass, the thickness needs to be around 33mm thick to withstand the force of impact. Toughened laminated glass is mostly required for walk-on floor glass as it is more durable in strength. To determine the desired thickness of your chosen glass skylight fixture, it all depends on the type of building the installation is being added to, the glass support structure, and the intended usage for the panels.

Tuffx skylight panels are made with clear toughened safety glass with double and triple-glazed options from 6mm in thickness. Head over to our skylight glass range to find the perfect glass pane size for your home needs.