Demystifying Rooflight Terminology

Skylights, often interchangeably called rooflights, roof windows, or even by brand names like Velux, come with a diverse set of components and features. Understanding the terminology associated with these architectural elements is crucial for making informed choices during installation and operation.

Actuators: Mechanisms responsible for electronically opening and closing skylights. Modern actuators offer various functions, including wind or rain sensors, and can be controlled via switch, remote, or dedicated mobile apps.

Baseplate: The part of the rooflight containing hinges for attaching the casement. Positioned between structural support timbers, it forms a critical component ensuring stability.

Bespoke Skylights: Custom-made rooflights tailored to specific requirements. Options include variations in glazing, colour, wood type for the liner, addition or removal of glazing bars, and the choice between opening or fixed casements.

Casement: The opening part of the rooflight containing self-clean glass units, fixed onto the baseplate hinges. It is the visible section once installed in the roof.

Coastal Location Rooflights: Rooflights designed to high standards suitable for coastal use, considering factors like high salinity or pollution in the atmosphere. Ideal for properties near coastal areas.

Condensation: Water resulting from the conversion of water vapor in the atmosphere. Understanding condensation is essential for managing the impact on skylights, considering temperature and humidity levels.

Conservation Rooflight: A design rooted in the 18th century, initially used for agricultural buildings. Recognisable by its low profile and slender appearance, adhering to conservation requirements to minimise visible framework.

Contemporary Skylights: Stylish and streamlined roof windows catering to modern aesthetics. These rooflights maintain a low profile, offer high energy efficiency with self-clean glazing, and typically lack glazing bars.

Escape Rooflights: Fitted with gas struts to stay open during emergencies, providing access or escape routes. Gas struts are pressurised cylinders allowing the casement to remain open unaided.

Gas Struts: Pressurised cylinders attached to rooflights, enabling them to stay open without external support, similar to the mechanism in a car’s boot.

Hand Winder: Mechanism for manually opening and closing rooflights within reach, often equipped with a handle or wheel for ease of operation.

Demystifying Rooflight Terminology Stella Rooflights

Pole Winder: Mechanism for opening and closing rooflights when out of reach, usually operated by a separate crank pole.

Head Detail, Jamb Detail, Cill: The top, side, and bottom sections of the rooflight, respectively.

Linking Bars: Bars used to connect skylights, creating continuous runs. Sometimes referred to as Studio-Linked by specifiers.

Listed Building: A structure officially designated for its special architectural, historical, or cultural significance. Changes to listed buildings require close collaboration with local authorities.

Overall Sizing: The maximum width and length of the baseplate, often covered by tiles or slates.

Pitched Roof: A slanted roof structure, with conservation skylights suitable for use within specific pitch ranges in different roofing materials.

Roof Window, Rooflight, Skylight: Synonymous terms describing the frameset with glass fitted into a roof opening to admit daylight.

Self Cleaning Glass: A technological advancement that simplifies rooflight maintenance. The glass, coated with a specially developed substance, breaks down dirt through a photocatalytic process and spreads rain evenly to clean the surface.

U-Value: Overall heat transfer coefficient measuring how efficiently a building element conducts heat. A critical factor in assessing the thermal performance of skylights.

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The Ultimate Guide to Conservation Rooflights

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