Roofglaze News

Jul 2010

By Richard Cliffe, Director, Roofglaze Limited

Over the last few years, much has been written about the positive contribution that rooflights can make towards meeting the requirements of Part L of The Building Regulations: a fact that is supported by independent research carried out by De Montfort University on behalf of NARM, the National Association of Rooflight Manufacturers, of which Roofglaze is an associate member.

The research indicated that compliant rooflights make a positive contribution to healthy internal environments, as well as reducing energy usage. This in turn reduces carbon emissions, helping to meet the requirements of Part L of the Building Regulations.

Inevitably, pressure to increase rooflight areas has led to concerns regarding the potential for causing unwanted increases in internal temperatures due to solar gain. Unacceptably high internal temperatures have a detrimental effect on building occupants and place increased emphasis on energy-hungry cooling.

However, whilst these are valid concerns, it is easy for today’s rooflight specifier to avoid these outcomes by simply selecting appropriate products and if necessary, seeking design guidance from a reputable rooflight specialist.

The first point to consider is the glazing material. Glass, solid or multiwall polycarbonate and GRP are today’s most commonly used glazing materials.

Glass and polycarbonate can be specified to provide varying degrees of light diffusion with translucent grades or textured surfaces. GRP is also translucent and therefore provides diffused light that’s ideal for industrial environments.

The latest, hi-tech Nanogel®-filled multiwall polycarbonate rooflights are particularly effective in terms of light diffusion, providing soft, even, deep light dispersion with no glare, in addition to unrivalled thermal insulation performance.

Nanogel®-filled rooflights have been specified by Tesco’s for a number of their new stores, including the world’s first ‘zero-carbon superstore’ at Ramsey, Peterborough.

For more specific requirements, various solar control glazing options are  available. These provide predictable results in applications where control of internal temperatures is a key concern. South facing areas of a building are typical of these.

An example of solar control glazing is Roofglaze’s ‘Cool & Clear’ polycarbonate range. Cool & Clear glazing can be specified on all Roofglaze polycarbonate rooflights, from modular domes to barrel vaults and other configurations. Cool & Clear glazing is a polycarbonate sheet that has been impregnated with a special additive that tints the material to cut solar gain by up to 75%, whilst maintaining high light transmission. The material also filters out 99.7% of harmful UV rays to minimise health risks associated with exposure to UV.

Where glass is the preferred glazing material, this can also be specified in a wide range of solar control options from all the major glass manufacturers – to provide varying degrees of light transmission with a choice of aesthetic effects.

Self-adhesive tinted films are also available for application to glazing, to provide solar control or reflectivity for privacy purposes. However, these should generally only be considered as a low-budget remedial solution, as the film surfaces can be easily damaged and poor adhesion can result in unsightly patches.

In conclusion, it would be wrong for rooflight businesses like ourselves  to make light of concerns over the very real potential problem of solar gain (pardon the pun). However, this is a subject that has been well and truly addressed with the introduction of a whole host of rooflighting and glazing products. This means that today, there can be no excuse for overheating buildings resulting from poor rooflight specification.

Based in St Neots, Cambridgeshire, Roofglaze Limited is one of the UK’s leading providers of rooflights and skylights, offering a complete range from modular domes and pyramids, to continuous barrel vaults, ridgelights, lantern lights and bespoke designs.