Building out a one-storey extension? If budget allows, a roof light can make a real impact to your space. Here's how to choose the right one for you. 

velux active smart home roof light -

Image: Active Smart Home roof light, Velux 

Whatever the concept of your new extension, roof lights, lanterns and windows are now available in such a wide range of designs that there is sure to be a style to fit your space. 

The aim of a roof light is simple - to bring as much light to a space as possible - but there's a few things that need to be considered along the way that will affect not only the aesthetic value of your project, but the budget too. 

Bespoke or off-the-shelf?

vale garden rooms house roof lantern light -

Image: Vale Garden Houses

Choosing a roof light that is a standard size is the route to a more cost-effective build, and in many instances is totally appropriate for the design, even if you need to get creative with how you use them. 

However, if every centimetre matters in your design, or you're looking to use glass roof windows in a more unusual or challenging way in your design, you may have to bite the bullet and incorporate the cost of a bespoke creation into your project budget. 

Design options 

timber roof lantern from westbury joinery -

Image: Westbury Joinery 

As varied as properties can be, so can the design of roof lights. Whether you choose a flat or pitched roof light, opt for a sleek thin frame or ornate orangerie style, it's usually more of a visual choice. However, it's important to consider the view not only from the interior, but the outside too.

If you're working with an architect, a specific product or style may have already been specified as part of the project (often even to have planning permission approved), but if not, it's worth considering it as part of your plan for the outside of your home. Is the extension designed to blend in with a period home, or stand out as a modern contrast - whatever your idea will undoubtedly affect your choice of roof light. 


glazing vision sliding roof light -

Image: Glazing Vision 

Roof lights don't always have to be static panels of glass, and your choice of product could offer you extra options for ventilating your space or even completely transforming it depending on the season. However, when it comes to roof lights, automatic controls are best practice for a more useful design feature. Velux's Active Smart Home roof light, for example, can now be controlled by Google voice assistant, while in this project by Glazing Vision, the entire glass roof light can be retracted in summer to create an indoors-outdoors space when the weather allows. 

Special applications 

iq glass roof light on angled side return extension -

Image: IQ Glass

Considering the practical applications of roof lights is important when specifying a product. For example, during hot summer months, if you've not opted for glass with solar-control features, the space may be too bright and hot to use comfortably. Equally, self-cleaning glass can be a good investment for designs where cleaning manually would be difficult, if not impossible. 

Explore features such as Electrochemic glass, which doesn't require blinds as it dims automatically in bright light, switchable glass, which can turn from transparent to opaque at the flick of a switch, and triple glazing, which is super effective at insulating and reducing noise from outside. 


Are you creating an extension with a roof light? Let us know by tweeting us @granddesigns or posting a comment on our Facebook page. 



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