Home Retrofit Planner

Home Retrofit Planner (HRP) is a comprehensive system for producing in-depth home retrofit surveys. It helps homeowners plan and execute energy-efficient retrofits, tailored to their specific needs.

1. It is flexible and detailed; it has the ability to take into account resident priorities, plans, and needs and building context. It is able to work down to individual window level and accommodate a range of - often complex - existing arrangements. HRP can model planned building alterations and extensions.
2. It stands out for its user-friendly scenario planning approach. It enables users to compare options and alternative approaches using measurable metrics that are useful in zero carbon planning and informing decarbonisation strategies. Moreover, it offers transparency by avoiding a "black box" approach and provides clear insights, allowing users to understand the implications of various options, such as the feasibility of fitting a heat pump.
3. HRP offers good integration of contextual location-based information. It incorporates data related to planning, radon, flood risk, and more. Furthermore, it enables the integration of site-specific contextual information, making it a versatile tool that extends beyond energy modelling alone. As the need for such information continues to grow, our HRP is positioned to become increasingly valuable in supporting decision-making processes.

HRP surveys are conducted by trained and experienced Retrofit Surveyors, who use the web application to profile the performance of the home and identify improvements. The surveyor creates a baseline model of the existing home and then uses HRP to create a number of potential retrofit scenarios - usually a minimum of 3, but more where further comparison of alternatives is useful. These are often based on low, medium, and high levels of intervention, though can be flexibly tailored to the homeowner's priorities and future plans, testing cumulative or alternative approaches to inform decision making about the retrofit strategy. The scenarios can be integrated with any non-retrofit works the homeowner may be planning and are aligned with their biggest concerns or budget.

A sample of the scenarios report we produce is here.

HRP has been used to plan retrofit works ranging from DIY projects to medium-sized measures costing several thousand pounds to large-scale projects with budgets over £200,000. To date, HRP has been used to deliver more than 500 whole-house retrofit assessments, with many homeowners carrying out recommended retrofit works. Every time an assessment is carried out, the insights gained are used to improve the tool further.

The HRP service provides access to the HRP tool, which is hosted on PPR's servers in a typical software-as-a-service arrangement. Users are provided with training on how to use the tool and are vetted to ensure they have the necessary skills to use it. Technical support is also available to help with building modelling, scenario development, and any software bugs.

"The HRP tool includes pre-calculated performance data for a wide range of common building elements and building services. This is particularly useful because you can almost always find existing options to match the surveyed building. On the occasions when something isn't covered, PPR is happy to suggest an alternative or add it to the database for future use. I've found that this approach simplifies the process and saves time in building an accurate picture of individual buildings, avoiding inaccuracies that can arise from oversimplified systems and the need for arduous individual calculations.

The report combines pre-populated text that explains common themes with free fields for the assessor to input project-specific information. This approach works well for me as it allows for personalisation of the reports. It breathes life into suggested measures through descriptive text that links them to specific client circumstances while also supporting readers in developing their general retrofit knowledge with well-targeted prewritten sections on common issues applicable to all clients, such as ventilation, air tightness, and heat pumps.

While the tool is simple to use, it does require the user to have a good understanding of retrofit risks and best practices. The tool does not provide guidance on applying measures in a specific order, and the inclusion of certain measures does not automatically trigger others. This flexibility allows the assessor to tailor the sequencing of measures to suit the property and client in a nuanced approach."

Amy Hield, Technical Lead at Cumbria Action for Sustainability

We work with community energy organisations and charities around the UK to implement HRP organisationally. At present we're not working with non-community energy organisations, and the route to using HRP for individual retrofit assessors/surveyors is through one of the organisations we work with.