Zenon Arc Rooflights

Barrel vault rooflights are popular in applications where continuous runs of rooflight openings are required in flat, low pitched, curved and standing seam or secret fix roofing systems, or where in-plane or individual domed or pyramid type rooflights are not suitable or adequate to provide sufficient light transmission effectively.

The provision of this style of rooflight allows for high levels of natural light to be provided into the building with all the associated benefits of natural daylight and energy saving. As an out of plane installation, barrel vault rooflights are usually mounted on kerbs or upstands in continuous runs to suit the application.  These upstands are generally a minimum of 150mm high for adequate and long-term weather sealing of the junction between the rooflight and waterproofing layer.

Zenon Arc barrel vault rooflights are supplied as double skin or triple skin insulated modular rooflight units containing the patented Insulator system, and are characterised by longitudinal ribs for extra rigidity. They can be supplied as an un-insulated panel where there are no specific thermal compliance requirements.

They may be constructed from Zenon Pro and Zenon Evolution rooflight sheets, depending upon the performance specification, durability and non-fragility periods required, to provide two daylight opening width options of 1000mm and 1200mm.

Zenon Arc Pro rooflights are manufactured using the conventionally reinforced Zenon Pro 24 rooflight sheets, and Zenon Arc Evolution rooflights are manufactured using the high strength, low embodied carbon Zenon Evolution LC1 outer sheet combined with a Zenon Pro liner.

When choosing the high performance Zenon Evolution, the system delivers embodied carbon levels that are significantly lower than the industry standard making a greater contribution to the target of overall building carbon neutrality.

Zenon Arc Barrel Vault Rooflights

System Features

  • The Zenon Arc comprises of Factory Assembled units manufactured from either Zenon Pro or Evolution panels.
  • Can be used with separate, in-plane liner
  • Opening width sizes: 1000mm and 1200mm
  • Finish: Translucent GRP
  • Non-fragile as tested to ACR[M]001 specification.
  • Suits most roof construction types
  • UKCA and CE marked to BS EN 14963

Zenon Arc Barrel Vault Rooflights Performance Data

To learn more about Zenon Arc rooflights, why not attend one of Hambleside-Danelaw’s CPD sessions, the sessions can be booked for your place of employment, or you can attend one of our sessions open to the public.  Contact the marketing@hambleside-danelaw.co.uk for more information.

For Zenon Arc DOPs, fixing details, and other relevant documentation please refer to our downloads section.

Product FAQs

Is a 10mm 4-wall polycarbonate a better insulation layer than the 4mm twin-wall option?

As an insulant, yes it is, but for the marginal improvement in the heat that is retained by it, the extra layers that both absorb and reflect light mean that the light transmission losses are higher. For some designs, this would be a sound solution, but in many cases the light improvement and lower embodied carbon of the lighter product delivers a better result.

For the best of both worlds, consider the use of Zenon Insulator. This can deliver improved U-values with minimal impact on light transmission, so the best of both worlds.

Why use Zenon Evolution in favour of Zenon Pro when the light transmission is worse?

Zenon Evolution might not always be the best choice for the project, however it brings many benefits. The glass reinforcement comprises continuous strands that run the length and width of the rooflight providing greater levels of tear resistance and greater safety without having to make the rooflight thicker. This means that it can be manufactured to a sharper profile shape to match the metal sheets better, under at the top and over at the bottom. This makes the sealing of the rooflight easier and more reliable.

Due to the increased glass content, the level of light transmission through the Evolution product is less, but the diffusion is greater. Lower levels of light transmission result in lower levels of solar heat gains, therefore greater areas of rooflighting can be used to improve the uniformity of light within the building and avoid areas of shadow.

The stronger thinner product uses less raw materials which reduces the amount of embodied carbon in the product and can also be more cost effective compared to thicker alternatives. Please see FAQs about design considerations, for more information on why specifying rooflights is an important component within building design.

What span can we achieve with your in-plane rooflights?

Span capabilities vary by profile depth and weight of rooflight sheet.  Maximum span recommendations can be found on our product data sheets, which can be emailed to you via our Zenon sales team.

Zenon Arc is a factory-built panel barrel vault rooflight system available in double skin configuration manufactured using either the Zenon Pro or Zenon Evolution type materials and with the choice of two additional ‘Insulator’ upgrade options. It is manufactured to accommodate spans or 1.0m or 1.2m and is extremely quick to install on site.

The rooflight needs to cover an opening more than a metre wide. What are my options?

Some roof sheet profiles are more than 1 metre wide as standard and we have tooling to make many such products. Often the rooflight pattern of an installation can include two or more rooflights adjacent to one another, depending on the daylighting requirements within the building. For other roof types, Barrel Vault Rooflights are available for daylight opening widths of 1000mm and 1200mm. Please contact us to discuss your requirements.

What type of rooflight do I need to use in a low pitch/standing seam roof system?

We can supply certain rooflight profiles to match these metal roof profiles, however there are usually strong technical reasons where this is not the best approach, and ‘out-of-plane’ barrel vault systems mounted on kerbs such as Zenon Arc would be a more appropriate solution. Please contact us to discuss your requirements.

What guarantees do Zenon rooflights come with?

Zenon rooflights have either a 25 year or 30 year Service Life Guarantee dependent upon choice of material.  Project specific service life guarantees can be issued for inclusion in O&M manuals upon request. As manufacturers of components fitted into or onto roof assemblies by others, we cannot offer any guarantees on non-fragility as there are too many factors beyond our control.

Have all Zenon rooflights been tested?

Yes. Rooflights must be tested for light, heat and solar transmission properties, together with fire performance. They’re are also tested for non-fragility in a representative assembly of the different construction details required for that system.

What roof pitches are your rooflights suitable for?

In-plane GRP rooflights are not recommended for use in pitches below 4°, although some system manufacturers may allow this, subject to the limits of their system guarantee.  They can also be used as ‘wall lights’ in vertical cladding applications where required.  For roofs with a pitch below 4°, or for some specialised roof systems, kerb-mounted barrel vault rooflights are often the best option. We supply a GRP barrel vault rooflight system, Zenon Arc. Contact us for further information.

Why are Zenon Rooflights not clear and does that mean I don’t get as much natural light in my building?

Zenon rooflights are manufactured from translucent, naturally-diffusing GRP. The light levels passing through Zenon rooflights can be comparable to transparent materials, subject to weight and specification. Unless direct vision is required through a rooflight, then diffused light is a more appropriate option. The light is scattered over a wider area reducing the uncomfortable effects of hot spots, glare and gloom within the building.

Do you offer bespoke rooflight manufacture?

We have tooling to match the vast majority of fibre cement and metal roofing profiles. If we don’t have the profile you need, we can produce the necessary tooling  at a cost depending on the quantity required. Sheet lengths are generally manufactured from 1.2m to 7.5m but can be made them shorter or longer to meet specific requirements. There would usually be additional cost associated with this. Please contact us for more information.