Changes to SAP calculations set to boost the adoption of continuous centralised ventilation systems.
The amendments, due to be launched in January 2012, have been given the green light by the Department of Energy & Climate Change and will reduce the current conservative performance ratings given to this ventilation technology when it is installed by a competent person.
Currently conservative ratings are applied in SAP calculations to the performance figures of centralised Mechanical Extract Ventilation (MEV) and Mechanical Ventilation with Heat Recovery (MVHR) because specific fan power (SPF) can increase if a system is not installed correctly, affecting efficiency. The Government therefore applied ‘in use’ performance penalties to the technology’s laboratory data results in initial SAP calculations to compensate, adding a 40 per cent specific fan power penalty to MVHR and 30 per cent to MEV systems.
From January, a developer can choose to have the ventilation equipment installed by a competent person and at the same time reduce these penalties. The scheme is the result of the ventilation industry developing training and competency plans linked to assuring installed system operation. As a result of this assurance a housebuilder that specifies a ‘Competent Person’ to install continuous centralised ventilation systems will be able to unlock a SAP Benefit which will improve a building’s DER.
Under the scheme, a trained contractor, who must be a member of a Competent Person Scheme, will ensure an installation is in line with competency requirements and complies with or at least meets the performance laid out in the original system design and complete a commissioning sheet capturing the installation details. This information will be submitted to building control and the SAP assessor and will reduce MVHR penalties from 40 to 30 per cent and MEV from 30 to 25 per cent, enabling developers to achieve a better value for their spend in SAP.
“This Competent Person Scheme comes at a time when the Building Regulations Minister is calling for a significant improvement in the way we build our new dwellings and fits well with the intended policy to apply ‘confidence factor’ penalties on whole dwelling performance unless there is proof the home has been built as designed. The Government has called for at least 90% of all dwellings built in 2020 to either meet or exceed the stated design performance,” explains Kelly Butler, Marketing Director at BEAMA.
For contractors the scheme offers an opportunity for them to both add value and differentiate themselves from their competitors while winning packages of work from developers. Meanwhile, manufacturers will benefit from a knowledgeable installer base which helps ensure satisfied customers and reduces call back rates. By using a competent person to install a ventilation system a unit will be optimised and so run efficiently and quietly resulting in happy home occupiers.
“At Vent-Axia we welcome the introduction of this Competent Person Scheme. As we move towards the Government’s target of all new homes to be zero carbon by 2016 it will be necessary to install continuous centralised ventilation. To meet this demand it is essential to train installers to fit the systems. By offering developers an enhanced SAP benefit this will encourage contractors to train to win work packages. As a result home occupiers that use approved contractors will benefit from quiet, efficient, effective ventilation,” says Lee Nurse, Marketing Director at Vent-Axia.