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What support does Lumen offer to architects, home owners, local authority specifiers and builders?


Whilst the needs of our customers may vary, the end results should always be the same. As such we believe that not only do our rooflights have to meet the highest standards but also the service that we provide.

From an architects perspective, we appreciate that our roof windows will ultimately reflect your design. Our experienced team are able to work with you to produce technical drawings and discuss installation queries. As a UK manufacturer we are able to offer rooflights in a variety of materials with several glazing options to meet tight deadlines.

Local Authority specifiers can take confidence from previous projects involving conservation officers and planning officers on projects overseen by the likes of National Trust, English Heritage and Historic Scotland. The Lumen range of roof windows provides products to suit both period refurbishments or modern new build projects. The Lumen range of Conservation Rooflights is fast becoming recognised as a market leader and a trusted brand for quality and service. Other products such as the Lumen Contemporary and Lumen Flat Roof range offer solutions for local authority buildings such as schools and hospitals.

As a building contractor/installer you can be assured that whilst Lumen rooflights are not the cheapest available, they do offer exceptional value for money. Manufactured to a high specification the entire Lumen range are produced in the UK to ensure product consistency. Lumen rooflights are simple to fit, reduce call backs and are available from stock. The ordering process is made easy and full installation support is provided.

The homeowner can be assured that Lumen skylights are not only manufactured to exacting standards in the UK but that our customer service is there to support you from the first enquiry through to the purchasing and beyond with our lifetime guarantee*. We care our about our rooflights and our customers and appreciate the investment made when choosing Lumen. We are not simply box shifters and are always happy to discuss your projects and recommend resources or contacts that you might find useful. Our range of stock sized rooflights are avaible for next day delivery but should these not exactly fit your requirements, we can also manufacture bespoke roof lights to suit both traditional or contemporary settings. *See guarantee details in our download section.


In your brochure you quote a clear viewable area, an internal rafter and an overalll size. Please can you explain how I size the rooflight required.


As the Lumen rooflight is fixed into the sides of the rafter, this is normally the most critical size. The clear viewable size is the glazed area that is viewable from the inside. This measurement takes into account the fitted interior liner that is positioned inside the opening section. The overall size is given to inform the installation team just how much space is required on the outside of the roof. However, much of the outer section will be covered by the tiles or slates so this is not to be taken as the viewable size from outside.


s there anywhere that I can view the range of Lumen rooflights?


Yes, Lumen Rooflight has recently opened a showroom at 3 RMD , Holsworthy, Devon, EX22 6HL.

The new showroom area provides customers an opportunity to view the range of Conservation, EVO and bespoke rooflights installed into a variety of roof tiles and slates. Visitors will be also be able to see and use the wide range of manual and electric actuators.

The roof light showroom is open Monday to Friday 09:00 to 16:00 with weekend and evening appointments available upon request.

If you would like to visit us and discuss your requirements, please call 0330 300 1090.


You provide lots of different sizes, which ones do I need?


We provide a range of sizes in our literature and on our website. The most commonly used size for installation is the "Internal Rafter" dimension. The width dimensions are critical as the fixing lugs are located on the sides of the rooflight however, we do provide around a 55mm tolerance in the quoted internal rafter. This gives the installer an option with the plasterboard. Quite often the installation involves the plasterboard being boxed around the rooflight. However in certain applications the winder may snag on the plasterboard at the bottom of the rooflight thus reducing the distance the winder can open the casement. If your rafters are particularly deep and this is likely to happen, it might be necessary to fit the bottom section of plasterboard at an angle. Providing the tolerance in our internal rafter height makes this process easier. If you do not wish to taper the plasterboard, you can simply add an additional timber piece across the head or cill to fit tight against the rooflight liner. As the end user, you will need to pay attention to the clear viewable size as this is the dimension you have upon completion of installation. These sizes are provided from the internal face of the American oak liner. The overall size is, as you would expect, the size of the complete rooflight. Please remember that much of the outer frame is covered by your slates or tiles, leaving an unobtrusive low profile rooflight in your roof. Should you require any sizing information prior to ordering or installation, please call us on 0845 050 8746.


I am interested in buying a skylight but I am not familiar with much of the terminology used on the various rooflight websites. Can you help explain what these mean?


There are many different ways to describe skylights and the components used in installing and operating them. Not only this but the term skylight is also referred to as many different things such as rooflight, roof window, sky light or occasionally people refer to them as Velux, who are of course is a manufacturer of skylights.

Actuators - are the mechanisms used to electronically open and close the skylights. Our standard product is the Kato and a rain sensor is available for this system. Other systems are available; please speak to one of the team for further details.

Baseplate - this is the part of the rooflight that contains the hinges for the casement to be bolted onto. The fixing lugs are located on the baseplate along with the American oak interior liner. This piece of the skylight sits between the structural support timbers.

Bespoke Skylights- this term is used to describe a rooflight which is custom made to your specification. This can be our range of conservation skylights, our contemporary rooflights or our range of roof windows for flat roof applications. You provide the sizes, we manufacture the rooflight.

Casement - this is the opening piece of the rooflight which contains the Pilkington double glazed glass units. This section is fixed onto the baseplate hinges. The casement is viewable once fitted in the roof

Cill - bottom section of the Rooflight

Coastal Location - We produce the rooflights to the very best of our ability. As such we are proud to offer our customers an exceptional guarantee. Whilst the guarantee gives assurances about our commitment to you and the quality of the product, there are some exemptions.
Firstly the location of your property is very important. Our zintec rooflights are treated with an Interpon APP120 primer before the application of a Cromadex Extra Life coating system for C3 Environment. As well protected as our products are the harsh salty environment of a costal location is likely to result in the faster deterioration of the protective coating and ultimately the metal.
As such we do not recommend installation of our standard range in coastal regions or areas which are subject to a corrosive or polluted environment. If your property is located in one of these areas, please talk to us about our range of paint options or stainless steel rooflights.
As with almost all exterior building materials, you should undertake regular maintenance to ensure that the product continues to work efficiently. We supply a copy of our guidelines with the order but please contact us on 0845 050 8746 should you require additional copies.

Condensation - condensation is the water that results from the conversion of water vapour in the atmosphere. The air in our homes always contains water vapour, which is usually invisible. The warmer the air, the more water vapour it can hold but there is a limit to the amount it can hold for a given temperature. Should you require additional information, please ask our team for a copy of the Glass & Glazing Federation fact sheet.

Conservation Rooflight - during the 18th century rooflights, in their most primitive form, were used to bring light into agricultural buildings. It therefore seems uncanny that todays rooflights are yet again providing an architectural design solution to the increasing trend of converting old or disused industrial buildings into domestic dwellings or business premises. Conservation rooflights are easily recognised by their low profile which means they sit flush and remain unobtrusive to the buildings original architecture. Another characteristic is their slender appearance as conservation requirements stipulate that a minimal amount of framework should be visible. This design feature becomes even more significant when rooflights are placed next to each other.

Contemporary Skylights - A stylish and streamlined roof window for customers who are seeking a more modern look for their roof glazing. The design remains low profile and unobtrusive whilst offering a high specification of energy efficient, self clean glazing

Escape Rooflights - although some rooflights are hinged on the side, our escape version are top hung to reduce any possible issues with light rain and to retain a matching appearance when installed alongside our standard range. Lumen escape skylights and are fitted with gas struts so the skylight stays open on its own accord. Supplied with a brass winding mechanism for daily use, the gas springs should only be deployed for emergency use. Further details can be found by clicking this link

Gas Struts- are pressurised cylinders that are attached to the rooflights so that they can remain open unaided in a similar way to the boot of your car.

Hand Winder- is the mechanism used to open and close the rooflights when the rooflights are within reach. Manufactured in the UK from solid brass these can also be supplied in a chrome plated finish.

Head Detail- is the top section of the rooflight

Jamb Detail-are the side sections of the rooflight

Linking bars-are the bars used to link skyflights together so that they are in continuous runs. Occasionally specifiers refer to these as Studio-Linked but we call them Lumen Link Light.

Listed building-is a building or other structure officially designated as being of a special architectural, historical or cultural significance. If your property is Listed you will need to work closely with your local authority before making changes to the building fabric. An excellent resource for Listed property owners

Non-Standard Rooflight-is a rooflight from our standard range that has a slight variation from others i.e. a different colour or a different glazing spec. Also see Bespoke.

Overall Sizing-the maximum width and length of the baseplate, much of which is covered by the tiles or slates.

Pitched Roof- is a roof structure where the roof is set at a slant. Our conservation skylights can be used between 17 and 70 degrees in slate and tile or 30 and 60 degrees in a pantile roof.

Pole Winder-is the mechanism used to open and close the rooflights when the rooflights are out of reach. Manufactured in the UK from solid brass these can also be supplied in a chrome plated finish.

Roof Window- is an architectural term for the frameset with glass which is fitted to an opening in the roof to admit daylight.

Rooflight- is another way of describing the frameset with glass in that is fitted to an opening in the roof to admit daylight

Self-Cleaning Glass- An important technological breakthrough was introduced to the UK in 2002, in the form of the worlds first self-cleaning glass, Pilkington Activ, considered by many to be an impossible dream. Pilkington Activ is effectively the same as conventional glass, but with a specially developed coating on the outside, that once exposed to daylight, reacts in two ways. Firstly, it breaks down any organic dirt deposits through a photocatalytic process, and secondly, when it rains, instead of forming droplets, the water spreads evenly over the surface and takes the dirt off with it. It is kinder to the environment than ordinary glass and it is the ideal choice for situations where cleaning will be costly or difficult.

Skylight-is another word to describe the frameset with glass in that's fitted to an opening in the roof to admit daylight.

Special Rooflight-is a sky light that is specifically designed according to the customers exact specification, see bespoke rooflight.

U-Value- often called the overall heat transfer coefficient and describes how well a building element conducts heat. Our standard Pilkington units have a U-Value of 1.2.

Viewable Sizing-is the unobstructed viewable area most notable the area of glass inside looking out. For Lumen products this is the measurement between the internal faces on the American oak liner.

Winding Crank-is used with the pole winder to open and close the rooflights when the rooflights are out of reach.


Your rooflights are manufactured with Pilkington toughened glass, does this mean that you can stand on them?


Definately not. Toughened glass provides additional safety to ensure that any falling objects do not come through the rooflight into the room below. Toughened glass is designed to shatter in safe pieces to minimise the risk of injury.

If you need to stand on a rooflight it will require specialist glazing. Please speak to us for further details.


I have both slate and pantiles on my property. Will the Lumen rooflight be suitable for both?


Yes. The Lumen range of rooflights sit as well in slate as they would in a pantile finish. In addition to our range of steel framed conservation rooflights, we are the only company to also offer a traditional cast conservation rooflight. We can supply installation details for many different roof types so please call our team to discuss your project.


We have just purchase a piece of land that we wish to build a new property in a traditional style.


Yes, the Lumen range of rooflights will add light and style to both period and modern buildings, in fact we have many clients building new properties and installing Lumen rooflights. As with all rooflight installations you will need to discuss the application of the rooflight with your local councils building control department, with particular reference to the Part L regulations.


We will be installing Conservation style rooflights into our Georgian farmhouse and wondered how we would ventilate the rooms.


Our stock range of Lumen rooflights have opening casements. Each rooflight is supplied with a beautifully crafted winder mechanism that is available in either brass or chrome. These winders will push the opening section out to a maximum of 300mm. As you are able to control exactly how far the rooflight opens you can have as little or as much ventillation as you like.


Can I buy Lumen roof windows online?


You can only purchase our Lumen rooflights on our website, www.lumenrooflight.co.uk.

We do not sell our products on any other website or auction site such as Ebay. Should you purchase a Lumen product from a secondary online source, it will not benefit from our guarantee.

If you are interested in our Conservation rooflight, EVO skylights, bespoke roof windows, Planus flat roof lights or coastal rooflights, please call our office on 0330 300 1090.

You can also purchase rooflights blinds, manual and electric winding mechanisms on our site.

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(08:30-17:00 Monday-Thursday & 08:30-16:00 Friday)

Telephone: 0330 300 1090 (local rate)

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Lumen Rooflight
3 RMD Business Units, Holsworthy Industrial Estate
Holsworthy EX22 6HL United Kingdom
Tel: 0330 300 1090
Tel: 01409 255120

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