Standards Development

Scope

This standard will aim to provide standardisation of the method of retrofit assessment described in PAS 2035. This assessment is completed as part of the process that records vital evidence to the stakeholders in the process. The standard will provide requirements for the level of expertise needed for the role.

This standard will replace Clauses 8.2-8.6 of the PAS 2035 document and will add clarity and context to other sections if so required.

The standard will cover the eight main facets of the retrofit assessment process:

1) Context: This section will contain information about how the dwelling should be inspected and reported upon:

a. The dwelling shape, size, features, structure, services, and suitability of the building for improvement.

b. Appraisal of the dwelling to allow for U values and moisture characteristics to be established. This should include construction type and materials.

c. Constraints presented by the site and the dwelling which may affect any proposed works, such as planning permission, special architectural, historical interests, subterranean elements and proximity to other structures.

d. Statutory limitations; rights to light, party wall issues, tree preservation orders and consideration of neighbouring properties.

e. Access to site, major roads etc.

f. Environmental features, orientation of the building, exposure to precipitation, wind, and solar gain.

g. Identification of existing energy efficiency measures.

2) Condition: This section will focus on the assessment of the condition of the dwelling and defects and shall include the following:

a. Location and severity of any construction defects; structural, condensation, damp, or mould growth issues.

b. Structural survey reports where required.

c. Description and condition of the installed building services; lights heating hot water and ventilation. A statement of the operational status for each system.

d. Destructive tests such as pull-out tests for fixing systems.

3) Occupancy: This section will focus on the two main facets of occupancy in PAS 2035:

a. The levels and type of occupancy of the dwelling, including special considerations such as vulnerable people; children, elderly, or those with disabilities.

b. A formalised occupancy assessment, which may affect the outcome of the energy performance calculation.

4) 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 (Annex C of PAS 2035 provides requirements around this topic):

a. Any continuous or intermittent ventilation system should be assessed in accordance with BSRIA BG46/2015.

b. Any ventilation system should be recorded and its area of coverage, condition, working status.

c. Identification, functionality, and condition of any background ventilation such as trickle vents, as well as purge ventilation, and ventilation paths, such as undercuts on doors.

d. Where required, an air permeability measurement should be carried out to recognised standard.

5) Energy Performance: The energy performance characteristics of the dwelling shall be recorded using RdSAP/SAP or PHPP. As such, the measured survey in Section 1 shall be added to, to provide enough information for this to be completed, also a corresponding method to allow for the occupancy of the building shall be included.

6) 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:

a. Where a building is defined as traditional, an assessment can be made using the simplified version of the BS7913 document.

b. Where a building is defined as protected then a full assessment of significance shall be made under BS7913.

7) Reporting: A report encompassing the data collection in sections 1-6 above shall be provided in a standardised format this data may include the following:

a. Energy performance data from RdSAP/SAP/PHPP shall be provided in a digital format.

b. Labelled photographs shall be provided digitally of all important features such as defects, site constraints, significant elements, RdSAP required photos.

c. Full copy of report including all other captured data.

d. Data protection requirements will be addressed.

8) Qualifications: The retrofit assessment is split into three paths according to risk. The path will dictate the level of skills required by the assessor, the standard will provide the correlating skills level and qualification to each of these paths.

Purpose

To be developed by CB/401/-/02