Changeworks Connects recap – February 2026

Retrofit Realities: Unpicking the challenges of the non-traditional timber archetype

This webinar explored how Changeworks uses archetype analysis to guide retrofit strategy development and decision making. It focused on the challenges and opportunities of retrofitting nontraditional timber homes, a diverse archetype with more than 140 subtypes.

Archetype analysis: An approach to strategic planning

Changeworks adopts a whole house approach to retrofit strategy development using archetype analysis to guide decision making. This approach groups properties into representative samples to enable deeper detailed analysis.

By setting quantitative and qualitative objectives and understanding baseline performance, the potential impact and feasibility of various improvement options can be explored through analysis of cost, carbon, heat loss and tenant impact.

Outcomes of the analysis can support funding applications, business case development, identification of pilot projects and align retrofit measures with planned maintenance cycles.

Archetype analysis can help estimate: 

• Current stock level performance 

• Suitable measures 

• Outcomes of various options 

• Stock level costs and potential risks 

However, further analysis is needed at individual property level to confirm final suitability of retrofit measures, precise costs and to address any non-standard property details.  

Key characteristics and challenges of the non-traditional timber archetype

The session highlighted key considerations of these properties such as:

• Moisture vulnerability, requiring careful insulation and ventilation design
• Fire safety considerations, especially around compartmentation
• Cladding decisions, which must balance aesthetics, cost and weather protection
• Significant performance variation, with some types already meeting proposed regulatory targets while others fall short

Insights from Changeworks Projects with Aberdeenshire Council include:

To reach required expected energy performance standards and reduce risks of fuel poverty, many non-traditional homes need: 

• Two layers of insulation (often external wall insulation combined with framefill or internal insulation) 

• Loft insulation upgrades 

• Major airtightness improvements 

• In some cases, MVHR may need to be considered to ensure adequate air quality in airtight buildings 
• Careful consideration and mitigation of interstitial condensation risk through a range of discussed methods  

Discussion themes

Participants discussed WUFI moisture modelling, the impact of external wall insulation on solar gain, and emerging evidence of summer overheating in south-facing homes.

The session also touched on the importance of tenant engagement and Changeworks’ ongoing Impact Evaluation and Tenant Energy Support work.