Sustainable design strategy: ventilation is the key to securing five star build status

The role of skylights in ventilation has increased in recent years as both architects and developers face mounting pressures to improve the energy efficiency of new buildings. Providing not only additional lighting, skylights contribute to sustainable design, helping to enhance indoor air quality as part of a natural ventilation strategy.

With people now spending up to 87%* of their time indoors, good ventilation plays a vital role in ensuring general occupant health and wellbeing. A lack of ventilation and breathability in buildings can lead to an increase or build-up in moisture, and with prolonged exposure to low air quality, occupants are also at potential risk of suffering from respiratory problems.

Good ventilation is an important consideration in the design and construction of all new homes and buildings. With this, architects are turning to natural ventilation solutions to meet the standards required– are skylights the key to a comfortable and well-ventilated future?

Natural Benefits

The importance of good ventilation has been further highlighted by an increase in uptake of voluntary building and construction standards. For example, the introduction of the British Science Centre’s Home Quality Mark (HQM) aims to set a voluntary national standard for all new properties. Filling some of the void left by the (now obsolete) Code for Sustainable Homes, the HQM uses an impartial five-star rating system to indicate a home’s overall quality to prospective purchasers by measuring its performance against a series of financial, wellbeing, environmental and social factors.

With over 97% of consumers stating that they would welcome the HQM, the standard could be set to become the industry-approved indicator of a comfortable, ecological, energy efficient and cost-effective home, as well as being a key market differentiator for developers in a period of significant sector growth.

Although ventilation itself is not covered within the technical standard, sufficient ventilation must be demonstrated if the desired five star HQM status is to be achieved. As outlined in official guidelines, a building with sufficient ventilation should aim to improve occupant health and wellbeing by helping to enhance air quality, reducing the risk of harmful chemicals being released from building materials and finishes (e.g. formaldehyde.).

Natural vs Mechanical Ventilation

There are two general means of ventilation – natural and mechanical – and it is important to consider both methods before deciding on which process is the right solution for a building. With ambitious government targets now in place surrounding energy efficiency, alongside a change in end-user needs, developers and architects are pioneering mass eco-build programmes, choosing natural materials and methods over mechanical alternatives.

As a form of natural ventilation, the benefits of skylights are numerous, and include reducing condensation and exposure to VOCs, moisture control and improved occupancy comfort – by providing residents with an accessible connection to the outdoors.

High performance skylights can also go some way towards achieving a range of other HQM credits, ‘Daylight’, ‘Temperature’ and ‘Internal and external noise’, contributing to the requirements of a minimum 2% daylight factor and maximum 35 dB equivalent continuous sound level in living spaces.

From a developer or facilities perspective, skylights are a passive solution, reducing overall operational, energy and long-term building maintenance costs. This is a stark contrast to its mechanical counterparts, with systems of this kind often being retrofitted, requiring a higher investment both in terms of installation and operational costs.

Mechanical systems such as air conditioners can also create air which is dry, and in some cases, take relative humidity levels below the ‘goldilocks zone’ of 30%-70% – the levels which are recommended for occupancy comfort.

Driven by Demand

There are three main types of skylights; ventilating (or roof windows), fixed, and tubular. They come in a range of different shapes, including flat, arched, domed, and pyramid, as well as materials including plastic or glass, and all are available with trickle vents, offering continuous ventilation. Manufacturers, such as VELUX, are responding to the increase in demand for skylights with high quality solutions, including bespoke modular systems – suitable for a variety of building types and spaces, from internal courts and studios, to offices and narrow corridors.

With standards such as the HQM set to become the industry-approved indicator of a comfortable, ecological and energy efficient home, natural ventilation systems, including skylights, could soon become a standard component in building design blueprints as architects seek to satisfy the demands required of them – both from occupants and developers.

Callum Tasker, operations director, Construction Materials Online

 

* The National Human Activity Pattern Survey (NHAPS): A Resource for Assessing Exposure to Environmental Pollutants