Before the refurbishment started, the local authority had around 1,500 bedsits right across the city. Known as zero-bed units, they were small – usually no more than 26 square metres – and as they aged, they became progressively less attractive to tenants.
Moreover, the more unattractive the location, the more ‘de-tenanted’ they became. So began a vicious cycle of vacancy, dilapidation and social deterioration.
Actions carried out:
- Passive-house standard retrofit
- Creation of a community Hub
- Training for the whole team on insulation works
- Post occupancy monitoring
In all, 22 bedsit apartments were amalgamated into eleven one-bed apartments as part of this phase of the project, undergoing a passive retrofit in the process. In addition, the community centre which forms part of the complex was also renovated to a very high standard.
During the refurbishment Enerphit was used, the passive house refurbishment standard which perfectly fit into the aim of helping elderly tenants particularly vulnerable to fuel poverty. Costs are low, maintenance is low and there are the health benefits associated with living draft-free in clean air.
The project was certified by MosArt on 1 May 2019, with a space heating demand of 21 kWh per square metre per year, comfortably below the threshold of 25.
The newly upgraded apartments have vastly improved thermal performance – up to 80% better than the previous units – and are fully compliant with the current building regulations.
Because the apartments will remain in the ownership of the council in the years ahead, one eye is kept on long-term maintenance issues.
Each of the St Bricin’s Park apartments is equipped with a Nilan Compact P exhaust air heat pump, which provides space and water heating, and ventilation. Insulation is accessible and replaceable (some of them have to be replaced every fifteen years).
- Space heating demand (PHPP, after): 22 kWh/m2/yr
- Heat load (PHPP, after): 11 W/m2
- Primary energy demand (PHPP, after): 127 kWh/m2/yr
- Heat loss form factor (PHPP): 2.9
- Overheating (PHPP): 0%
GROUND FLOOR
Before: Uninsulated concrete floor
U-value: 0.73 W/m2K
After: Existing concrete floor with 20mm Smet floor screed, followed below by 62mm Enviroform E-Therm Slim panels including 2 x 6mm ship lapped mineral boards & 50mm Kingspan PIR floor insulation. Some deeper sections have an additional layer of 50mm QuinnTherm PIR floor insulation. U-value ranges from 0.18-0.23 W/m2K
HEATING SYSTEM
Before: 20-year-old gas boiler & radiators.
After: Nilan Compact P exhaust air heat pump w/ heat recovery ventilation distributing heat through ventilation ducting. Plus, three small electric radiators in each apartment, controlled by the Nilan unit.
VENTILATION
Before: No ventilation system. Reliant on infiltration, chimney and opening of windows for air changes.
After: Nilan Compact P — Passive House Institute certified to have heat recovery rate of 75%.
More information can be found here.