Low carbon ventilation
I seem to have been writing about the need for old buildings to ‘breathe’ forever but the fact is that all buildings need to have air movement within them, whatever their construction. With the emphasis now on airtight, energy efficient homes the issue is becoming ever more important, both in new build and retrofit projects, a fact driven home when I attended a recent briefing by Vent-Axia.
Vent-Axia is one of “the leaders in energy efficient ventilation technology” and, perhaps unsurprisingly, the company has welcomed the publication of Approved Documents for Part F (Means of Ventilation) and Part L (Conservation of Fuel and Power) of the Building Regulations 2010, due to come into force in October.
Ronnie George, Vent-Axia’s managing director, believes these documents represent an important “step change” in Building Regulations. “If we are to meet the UK’s carbon targets and reach zero carbon homes by 2016 it’s essential to meet staged efficiency targets. These sweeping changes to the Building Regulations set out a clear agenda for low carbon ventilation, as well as encouraging an increase in the uptake of renewable heat technology.”
The degree and type of ventilation required depends on how ‘leaky’ the building is but the new regulations favour continuous ventilation rather than intermittent fans. Continuous ventilation performs better in SAP (Standard Assessment Procedure), is easier to specify and standardise and does away with the need for trickle vents. It seems that what we’re likely to see is an increased adoption of whole house Mechanical Extract Ventilation systems (MEV) and Mechanical Ventilation systems with Heat Recovery (MVHR). To maximise carbon saving specifiers will need to choose units which are both effective and energy efficient.
Importantly, for the first time, Part F will require post-completion testing of ventilation equipment with the aim of ensuring that ventilation not only delivers the required airflow, but does it efficiently and quietly. Installers will therefore need a greater understanding of ventilation requirements.
Traditionally it’s been the electrical contractor who has installed ventilation equipment. One interesting consequence of the regulations is likely to be a change in the contractor base because, with the pipework required for ducting and the calculations needed to comply with the Regulations, the skill set is much more akin to plumbing. With this in mind it’s noteworthy that Vent-Axia has now entered the heat pump market, offering both air and ground source systems.
Regarding the move to airtight homes, combined with increased insulation, combined (often) with underfloor heating, has sufficient attention been paid to the effect this has on timber products in the property? As a supply/fit service for hardwood flooring I have recently seen floors react in a way I have not seen in the previous twenty years.
We have always had a strong environmental policy and support the move to energy efficiency but I feel there is a lack of understanding on the part of architects/specifiers regarding the implications of recent inovations.
This is an area that certainly needs to be given consideration and I know many flooring suppliers only recommend certain grades of flooring for use with underfloor heating. It would be interesting to know of specific problems that you’ve had. Does anyone else have thoughts?
I first came across Mechanical Ventilation on visits to Scandinavia and have been trying to include a system in my own home ever since. They successfully integrate systems into many of their historic buildings. I love the air quality that a system achieves and it removes the classic “heating on, window open” scenario we often have in the UK. It also apparently reduces airborne dust – what is there not to like!
[…] in highly energy efficient homes, states: “Recent BRE discussions with UK manufacturers of MVHR (mechanical ventilation and heat recovery) systems suggest that there is no market for replacement […]