Airs and Graces
Written for Windows Active October 2008 issue
Having supplied hardware lines for almost twenty years, including ventilation products, Carl F Petersen draws on its experience to provide an overview of ventilators with details of products and applications. John Mitchell, Head of Technical Support for Carl F observes that a vast range of product titles and associated terminology have developed and, in this report, an overview is provided to clarify ventilation categories.
Adequate ventilation has an impact on everyone involved in the window supply industry - it is an essential pre-requisite for many applications. The appropriate products therefore need to be identified, selected, supplied and fitted. Cutting through the complexities of the ventilation sector's vocabulary, there are three main categories of airflow systems: through frame, overframe and glazed in.
At Carl F, we work in partnership with Greenwood and have supplied the company's ventilation products for over a decade. Specialising in the design and manufacture of domestic ventilation products, Greenwood also offers extraction solutions for both trade and retail sectors. With over 120 years' experience, the company has established a strong reputation for simplicity in application, style and acoustic properties. In this article, I will draw on examples from Greenwood's ventilation product portfolio which are available from Carl F.
Through frame/slotvent solutions
Through frame ventilation goes through the head, frame or sash of the window and slotvents are the most popular description for products that fall into this category. Todays through frame ventilators are discrete, slim-line and stylish - they are designed to provide optimal air performance with minimal visual impact. New clip fit variants have been developed for through frame products and this approach helps to reduce installation time.
The key to through frame ventilation is the combination of adequate ventilation and aesthetics - the product has to be sympathetic to the look of the profile and leading ventilation manufacturers provide products in white plus colours to complement natural materials. Options are also provided for internal and external parts. The stylish D type range from Greenwood, for example, features a fly screen and provides unobtrusive ventilation for PVC-u or timber windows. With external louvered grill, the front operated ventilator incorporates specially designed ‘hydro-shedding fins' to ensure that rain falls away from the window frame.
Overframe ventilators
As indicated by the title, overframe ventilation products sit on top of the profile. The application tends to prohibit retrospective fitting of this type of ventilation into existing properties and overframe solutions are therefore predominantly used for new-build schemes.
Greenwood's Nu-Build overframe ventilation system is designed to prevent the need for routing through the frame. In-house manufacture ensures correct levels of ventilation are provided in line with current Building Regulations.
A key design feature of overframe ventilators is to be sympathetic to the room - in other words, the product should not overtly draw attention. Slim and unobtrusive aesthetics are the order of the day with overframe ventilation. Once installed, the ventilator should complement the window, blending and becoming part of the structure.
Glazed in ventilation
Again as the name suggests, glazed in ventilation solutions are installed integrally within the glass aperture. The glazed in option is a useful approach where space restricts use of overframe products or where aluminium is the preferred material. As people like to maximise their glazed area, we have found that this route tends to have niche appeal, with the majority of applications being in the social refurbishment or the new build commercial sectors.
Ventilation variables
Acoustic ventilation solutions can fall within all three categories previously mentioned but, in general, are used in through frame ventilation systems. Acoustic options are worthy of individual mention: with growing use of brownfield sites for new build development, the need to minimise noise from neighbouring roads, industrial sites or airports is increasing. Additionally, the issue of noise is set to become a planning consideration under the PPG24 planning policy guide. Where noise issues are a planning condition, it may be necessary to install acoustic ventilation solutions that provide the required replacement air into the dwelling and reduce noise intrusion for the occupants. Meeting this need, Carl F offers the Greenwood Airvac Acoustic Humidity Control Ventilator as this provides effective noise protection, humidity control and features a self regulating internal mechanism.
Through stocking Greenwood's products, Carl F provides a comprehensive range of quality ventilators across all categories including through frame, glazed in and overframe along with variables such as acoustic options. All products have been tested at third party accredited test houses in conjunction with BS EN 13141-1 Clause 4 Ventilation for Buildings.
Carl F staff are fully versed in the technical capabilities of Greenwood products and can support customers across all sectors for their ventilation needs.
