When Denise and Neil Gaydon bought The White Lodge, an iconic art deco period property in Adel, Leeds, intending to convert it and add a sizeable extension, they turned for a third time to ADM.
The first time they had used ADM’s services had been with the renovation of a bungalow near to The White Lodge. Both properties were close to the Ring Road and therefore affected by air pollution caused by heavy traffic. Denise and Neil are both asthma sufferers, so they were also particularly concerned to eliminate any potential causes of allergy.
ADM installed Mechanical Ventilation and Heat Recovery (MVHR) systems in both properties, ensuring each would provide a healthy living environment for their occupants. In such circumstances filters need to be checked frequently and replaced regularly, so proper system-maintenance is essential.
In between these projects, the couple had called on ADM to retro-fit a MVHR system in a flat their son had bought in the King’s Cross area of London, where again the air quality was very poor.
Fully understanding and appreciating the physical and psychological benefits of breathing fresh filtered air, the couple were keen to install a MVHR system in their new home. Their aim was to retain the character of the property while making it run with the efficiency of a modern home, including significant insulation, new underfloor heating systems, better windows and generally sealing the interior from external weather. They also intended to have wet rooms, ie bathrooms with floor drains. They knew that the MVHR system would obviate potential problems with humidity and damp, and deliver cost-savings from recycled heat.
The extension is one-third of the total area of the completed dwelling, and was built using structural insulated panels (SIPs). These are quick and easy to use for walls and roof elements. SIPs are Inherently insulated and are joined together with a special tape to guarantee a seal as close to airtight as possible – often the seal is so airtight that MVHR becomes a requirement, for example in Passive House certified projects. On occasion the construction may be to nominal Passive House standard but is not formally certified as such to save cost. For this project the architect aimed to achieve an air permeability level below or equal to 5m³/(h.m²) if possible.
With a MVHR system, only two external penetrations per unit are needed for house ventilation, contrasting with one for each wet room if extractor fans are used. Also, with extractor fans trickle ventilators in windows would have been a requirement, which would not have been suitable for a build intended to meet such a high standard.
In designing any system ADM choose the most suitable combination of components for the specific dwelling, taking into consideration aspects such as the location of plant (access for maintenance included), the position and appearance of air valves, noise attenuation, control strategy and zonal distribution where multiple units are required. Specifications always conform to the Domestic Ventilation Compliance Guide 2010, Building Regulations Part F (England and Wales) and the Technical Handbook 3.14 (Scotland) as appropriate.
In this instance the size of the property and some structural features meant it was best to use two medium-capacity units, one for the ground floor and one for the first floor. Limited voids, timbers that could not be worked on and architectural features that had to be retained meant that duct-routing would be simpler using smaller diameter ducts. The choice of a semi-rigid manifold system was the key to minimising the impact on the internal structure and the available void access. A single larger unit would have required larger diameter ducts which could not have been accommodated.
On ADM’s recommendationand low running costs. These units are also Passive House certified.
The system was commissioned by one of ADM’s approved installers. Having an NICEIC accredited competent person carry out this work improves the SAP rating for the property (https://www.gov.uk/guidance/standard-assessment-procedure).
Looking back on their achievement, the couple commented: “We are delighted with the result, where in the middle of winter the combination of the MVHR and heating systems creates an environment best described as every day feels like a summer’s day, with lovely fresh air.”