SHDF Wave 1 – Oswestry
Measured across our retrofit programmes
- 2,493homes with a post-works EPC
- +11average SAP points gained
- D → Caverage band movement
- 99.6%finish at band C or better
Crawford & Co assessed and coordinated these homes. Figures cover every programme where works are complete and a post-works EPC has been lodged, September 2026, and are not specific to this project.
Overview
For a housing association in Oswestry (via the principal contractor), Crawford & Co Surveyors delivered 27 retrofit assessments and coordinated the 27 retrofit works that followed under SHDF Wave 1.
Scope: External Wall Insulation (EWI), loft insulation and window and door upgrades.
Approach: a comprehensive assessment method identified energy-efficiency opportunities in each home; coordination then ensured measures were installed to standard with minimal disruption to residents.
Outcome: a meaningful reduction in carbon emissions and improved energy performance across the stock, delivered smoothly and compliantly.
Naomi
Project Manager
Strategy
Fabric
Wave 1 stock was predominantly system-built and cavity construction. Pre-existing defects are the rule rather than the exception on this kind of stock: dampness, condensation and mould, cavity wall tie failure, roof slumping and spread, timber decay and lintel failure. Every one of those has to be resolved before insulation goes on.
Identifying them at assessment is what makes enabling works a planned item rather than a mid-programme surprise.
Fabric measures were then specified per property — loft, room-in-roof and flat-roof insulation, cavity or external wall insulation, underfloor insulation, and replacement windows and doors — rather than issued as a standard package.
Service
Ventilation is designed alongside airtightness, not after it. Sealing a home without addressing how it breathes moves a moisture problem rather than solving it, so extract ventilation forms part of the same specification as the fabric work.
Heating and hot water measures are matched to the demand the fabric measures leave behind, so that plant is sized for the improved home rather than the original one.
Renewables
Where a property suits it, solar PV is added after the fabric measures, so that generation offsets a demand already reduced rather than masking one that has not been. Roof orientation, structural capacity and the condition of the existing covering all decide suitability, and the assessment records that rather than assuming it.
Vital Statistics
Properties in scope: 27.
Crawford & Co scope: Retrofit Assessment, Retrofit Coordination, Retrofit Design.
Measures installed: External wall insulation, loft insulation, window and door upgrades.
Programme period: 2022 to 2023 (indicative).
Each assessment records the property’s construction and its modelled performance before and after the proposed measures — space-heating demand in kWh/m² per year, carbon in kg per year and estimated energy cost. Figures are held per property rather than averaged, and are available to the client in full.
Detailing
The main technical risk on Wave 1 was installer familiarity with PAS 2030. An experienced coordination team is what catches paperwork discrepancies early and feeds them back before they become compliance problems at lodgement.
Our retrofit condition report was developed in house and approved by both the scheme provider and TrustMark. The work behind it contributed to our managing director’s appointment to the BS 40104 steering group — the British Standard for retrofit assessment. Where PAS 2035 leaves a technical question genuinely open, we take it up with the standard’s authors rather than guess.
Further Data
Standards
PAS 2035 / PAS 2030
Comfort
The measure of this work is a home that is warmer, drier and more affordable to run, and that stays that way. Lower heat demand is only part of it — even temperatures, humidity that stays under control and plant that runs quietly all decide whether a resident actually feels the difference.
Residents live in these homes throughout. Capturing everything needed in a single assessment visit exists for exactly that reason.
Monitoring
Coordinators quality-check every assessment before it reaches design, and the scheme runs with a live view shared between client, designer and installers so that discrepancies surface in days rather than at handover. Regular review meetings with client, designer and installers run for its duration.
Post-completion documentation is prepared for TrustMark lodgement through secure data sharing.
Social Value
AwaisSocial value leadDuring this project Awais was on a Surveying Technician Apprenticeship, funded directly from this contract.