Planned occupancy | Two adults occupy the property almost continously, other than the "school run" on weekdays. A further two adults and one young child visit the house on a daily basis for 4-6 hours. |
Space heating strategy | Ground source heat pump solution serving radiators with LTHW @55 deg C. Radiatiors proposed as slimline low water radiators with low efficiency, high output. |
Water heating strategy | Instantaneous hot water via integrated thermal store within indoor Ground Source Heat Pump unit. |
Fuel strategy | Ultra low all electric solution, offset by roof photovoltaic electricity generation. |
Renewable energy strategy | High efficiency ground source heat pump. Roof mounted photovoltaic electricity (3.7kWp as a maximum - this figure is constrained by the input of the efficiency with SAP for the groud source heat pump, which runs at 400% and not 320%, as inputted. |
Passive Solar strategy | High performance low solar transmission glazing on the property which has windows on South-East and North-West elevations. A garden to both front and rear increase likelihood of tenants opening curtains. |
Space cooling strategy | Comfort cooling is possible via reversible ground source heat pump operation. Openable windows for natural ventilation for most of the cooling season. |
Daylighting strategy | No changes to the fenestration were possible in this retrofit proposal, but the new heating system with slimline radiators does allow more flexible planning of furniture, which could allow better daylight access through the existing glazing. |
Ventilation strategy | Passive ventilation via openable windows and trickle vents. Extract fans in kitchen, bathroom and ground floor toilet. |
Airtightness strategy | Significant improvement to gaps and cracks in envelope, targetting 3m3/m2hr. |
Strategy for minimising thermal bridges | Areas considered include junctions between external walls and roof, where refurbishment has taken place since the original construction. Window to wall junctions and door jamb are considered using specially-fabricated "Passivhaus" windows and doors that address thermal breaks. |
Modelling strategy | Whole house dynamic modelling was undertaken in an iterative manner using ies ve software, SAP 2005 9.81 + SAP extension - see energy forecast below. ies ve software used with SAP interface (SAP2005 9.81 via JPA Designer vr 4.04b1 build 002). |
Insulation strategy | High performance TARGETTED roof insulation upgrade following detailed thermo-imaging report and air tightness testing undertaken during phase 1. Triple glazing with target u-value of 0.7W/m2k is the proposed upgrade to the existing double-glazed windows. |
Other relevant retrofit strategies | We are planning to carry out our package of retrofit measures with tenants remaining in the dwelling during the proposed works. We intend to demonstrate our approach can be undertaken with minimal disruption to the tenants and with no associated temporary re-housing costs. Due to the Landlord owning and managing all external land in between properties, there is the opportunity to install external ground source loops for up to 5 properties with potential to activate 1 property in Phase 2 leaving four ground loops capped off for future use. (subject to funding availability). Low energy lights, appliances, cooking and water-saving devices are also going to be supplied and installed. |
Contextual information | Additional data logging devices and clear metering for easyily controlled technology proposed to provide enhanced monitoring feedback to exceed TSB base specification is proposed, following discussion with current tenants that they are not especially energy-conscious at present and would benefit from support in this regard. The tenants have lived in this property for decades and have habits that might be challenged by the retrofit! |