Retrofit assessment
A retrofit assessment is the process of surveying, inspecting, assessing and recording the relevant characteristics of an existing dwelling ...in order to provide sufficient information for the preparation of a retrofit. This role is mentioned in PAS 2035, which is the British Standard for retrofitting dwellings, first published in 2019, and most recently in 2023, it outlines how retrofit projects should be managed and delivered.
Figures by the Trustmark from November 24, indicate that some 225k retrofit assessments have already been carried out in the UK. Following the PAS standard a piece of work regarding a standard for UK retrofit was started by RICS and published in their document 'Residential retrofit standard: RICS Professional Standard UK, as a 1st edition in March 2024, effective from 31 October 2024.
The BS 40104 Assessment of dwellings for retrofit, will effectively formalise and expand on this work, the new British Standard with effectively replace clauses 8.2-8.6 of the PAS 2035 document and will add clarity and context to other sections if so required. The current broad scope structure of the BS 40104 Assessment of dwellings for retrofit as developed by the CB/401 BSI Committee - Retrofitting Energy Efficiency Measures is as follows (for updates follow the BSI link above):
| Context - how the dwelling should be inspected and reported on |
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| Condition - the assessment of the condition of the dwelling and defects including: |
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| Occupancy - focussing on the two main facets of occupancy described in PAS 2035: |
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| Ventilation - Key to healthy homes is a functional ventilation strategy, as such a comprehensive understanding of the dwellings existing ventilation system should recorded, this includes (see also Annex C of PAS 2035): |
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| Energy Performance - The energy performance characteristics of the dwelling. |
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| Significance - The architectural or historical context of a dwelling is key to the provision of a sensitive retrofit. Where a dwelling is, or forms part of, a protected dwelling (Listed, part of a conservation area or within a world heritage site for example) or traditional (defined as “constructed with solid brick or stone walls, or timber-framed walls with any infill”), then it should be treated in a specific manner as part of the retrofit assessment: |
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| Reporting - encompassing the data above provided in a standardised format and may include: |
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| Qualifications - |
[edit] Related articles on Designing Buildings
- Alterations to existing buildings.
- Do the building regulations apply to works to existing buildings?
- Demolition.
- Material amendment.
- Material change of use.
- Minor material amendment.
- Non material amendment.
- Change of use class.
- Planning permission.
- Permitted development.
- Principal designer.
- Renovation v refurbishment v retrofit.
- Retrofit project roles.
- Types of works to existing buildings.
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