What technology did
the pilot test?

Smart sensors across a sample of 121 Bromford Flagship properties within its portfolio were installed to understand how the information could be used to scope, plan and deliver a programme of retrofit interventions.

Senze's measurement-based approach utilises room-by-room smart sensors and energy meters to continuously monitor thermal conditions, including temperature, humidity, pressure and pulling live energy consumption data. These sensors link into a software platform which uses digital twin models to monitor building performance and assess energy use.^dBased on the measured data collected, the platform simulates retrofit options, assessing their relative cost, expected energy savings and carbon impact. This aims to make use of room-level measurements to identify interventions that will be most effective and have the greatest impact, targeting areas of the property where improvements are most needed.

Senze's algorithmic approach to recommending targeted interventions based on the data collected is a key strength of its service offer. It was identified for this pilot as an example of an 'intelligent measured data' approach. Senze's platform also allows users to connect directly with suppliers to procure the recommended retrofit interventions.

Further detail on the technology and platform used in the pilot can be found in the Appendices, and in Birmingham City University's verification of the methodology on p3 of this chapter.^e

Figure 2: Overview of Senze’s process

^{Pre-assessment}^{Analyse and scrape publicly available data to assess the portfolio to understand where to prioritise sensor installation.}

^{Digital twin capture}^{Utilise technology to scan all rooms in a property, capturing structural dimensions and digitising them into a 3D 'digital twin'.}

^{Sensor and meter}
^installation^{Install sensors throughout each property to monitor thermal conditions, and link into energy meters to pull consumption data.}

^{Live thermal and energy analysis}^{Take continuous readings to calculate live thermal measurement analysis on a room-by-room basis.}

^{Recommendation and optimisation}^{Based on data collected, simulate retrofit options, assessing relative cost, expected energy savings and carbon impact.}

This service is delivered at a typical cost of £1,500 per property.

_{^d A digital twin is a virtual model of an object, a system, or a process. It is connected to its real-world counterpart by a 2-way flow of right-time data, meaning it mimics it in all aspects (definition from the}_{Department for Business and Trade}_)._{^e See ‘Appendix 4: A Measured Approach to Retrofit’ and ‘Appendix 5: Birmingham City University Verification Findings’ in 'The Science Behind The Insight Pilot Study Report, for further details.}

Assessing against the 'traditional' approach to retrofit

This pilot project is based on an assessment of the expected effects of the technology's data collection and retrofit recommendations. The works themselves have not yet been carried out and so this report explores the effects we expect to arise from use of this measurement-based approach, assuming the recommendations from the technology deployment are implemented.

The assumed counterfactual used in this pilot study is Bromford Flagship's existing programme of retrofit interventions (both planned and historic). There were differences observed in how Bromford and Flagship approached their respective retrofit programmes (their existing retrofit programmes pre-date their merger and so need to be treated separately). Generally, though, both organisations followed a full PAS 2035 compliant process, submitting cost estimates in line with their WH:SHF applications.^f

Both programmes used a combination of asset management systems and EPC-modelled data to identify which properties require improvement works (i.e. those rated EPC D or worse), and to recommend appropriate retrofit interventions.

This is broadly in line with the traditional 'modelled' approach to retrofit seen in the social housing sector, where upgrade measures are based primarily on assumptions derived from EPC ratings and SAP calculations rather than on measured property-level data.

Further details on the assumed counterfactual and the methodology behind the comparison can be found in the Appendices.^g

_{^fPAS 2035 is a standardised, whole-house process for upgrading homes to improve energy efficiency in line with the UK's official domestic retrofit standard. It involves a detailed property assessment, a risk-based design pathway, and usually a fabric-first approach that prioritises reducing energy demand before installing new technologies. Works must be overseen by accredited professionals, with quality assurance, post-retrofit evaluation, and resident handover built into the process. All WH:SHF-funded retrofit measures must comply with PAS 2035.
^gSee 'Appendix 10: Cost comparison methodology' in The Science Behind the Insight for further details.}

Birmingham City University – Verification of Senze Method

Birmingham City University (BCU) undertook an evaluation of the intelligent measured data approach used by Senze as described in this report. We sought to ascertain the viability of the Heat Transfer Coefficient (HTC) measurement, the economic evaluation of refurbishment options and evaluate the ancillary features of the Senze platform, such as indoor air quality.

The evaluation was conducted by a detailed dynamic simulation using pilot data industry leading IES software + SAP and the evaluation of operational data provided by Salford University (Salford) and benchmarked against a co-heating test and conducted in a test house under controlled conditions.

Evaluation confirmed that:

Results from pilot and co-heating test comparison were aligned and the Senze calculated HTC was found to be within 1.3% of Salford's measurement.
The simulation exercise of two houses monitored and evaluated by Senze in real-time, established that Senze HTC results were within range of expected values, accounting for assumptions in simulation and confidence intervals. This similarity demonstrates the adequacy of Senze for calculations for assessing retrofit options.
Whilst the energy reduction and costing of retrofit options was reviewed through simulation and showed that the Senze system produced good order of magnitude benefits and costs, the variance in retrofit installation costs must be recognised, as final costs might differ from construction cost databases. For the purpose of this project, independent cost data and Bromford Flagship’s actual costs (see Appendix 10, Cost Comparison Methodology) were used to ensure results were robust.
The Senze monitoring of internal temperature and humidity conditions can be enhanced by it measuring indoor air quality parameters which are presented in the dashboard, assisting in the more accurate evaluation of indoor environmental quality and avoidance of unintended consequences.