Delivering portfolio-wide PAS 2035 archetyping and costed improvement modelling to underpin a 30-year Target Energy Pathway.
Project Overview
- Client: Ark Consultancy (commissioned on behalf of Taff Housing Association)
- Sector: Social Housing / Housing Association
- Location: Cardiff, South Wales
- Services Provided: Decarbonisation feasibility Study – Archetyping, PAS 2035 Retrofit Assessment, Costed Improvement Modelling
- Scale: 1,600-property portfolio, assessed via 18 representative archetypes
- Target: Interim EPC C (SAP 74), long-term EPC A (SAP 92); 30-year Target Energy Pathway aligned to the Welsh Housing Quality Standard (WHQS 2023)
The Challenge
Taff Housing needed a genuine, evidence-based Net Zero roadmap for their entire 1,600-property portfolio – but surveying every single home individually simply wasn’t realistic within the project’s timeframe or budget. Ark Consultancy needed robust, defensible cost data at a portfolio scale to build Taff’s board a 30-year Target Energy Pathway, without requiring exhaustive, home-by-home surveying to get there.
The Solution
Portfolio Archetyping & Costed Improvement Planning
Rather than surveying 1,600 homes, we identified 18 representative archetypes across the portfolio and validated them through targeted on-site PAS 2035 assessments, capturing genuine fabric and ventilation data rather than relying on desktop assumptions alone. For each archetype, we modelled costed improvement pathways across fabric, services, and renewable measures – right down to individual line items – and extrapolated those costs across every property sharing that archetype, turning sample-level data into genuinely portfolio-wide cost projections.
The Outcome
Ark Consultancy came away with robust, costed improvement data extrapolated across the full portfolio – the evidence base used to build Taff’s board a 30-year Target Energy Pathway aligned to the Welsh Housing Quality Standard. The archetyping and per-archetype cost modelling delivered genuine portfolio-wide financial clarity at a fraction of the cost of assessing every property individually, giving Taff Housing’s board a defensible basis for long-term investment decisions.
Client Testimonial
We have worked with Building Energy Experts on a number of projects and have consistently found them to be professional, knowledgeable, and collaborative. They work closely with our team to ensure that we meet the aims and expectations of our clients, often going above and beyond to deliver high-quality outcomes. Their reliability and commitment make them a valued partner in our work around social housing decarbonisation.
— Luke Beard, Assistant Director of Technical Services, ARK Consultancy
