Rooftops and a church tower across a Kirklees town, West Yorkshire

Case study · Kirklees Council, West Yorkshire

Failed cavity fill taken out, the walls dried and refilled, in homes people were living in.

A framework programme for Kirklees Council’s Homes and Neighbourhoods service across Huddersfield, Dewsbury and the wider borough, led end to end by Miles Sharples, now Managing Director of EnergyGiants. The office team and the crews who delivered it are the team now at EnergyGiants.

51 homes by July 2026²£200,000 contract³December 2025 to March 2028Cavity wall, ventilation, damp proofing

The numbers from the programme

Homes completed by July 2026

Each one extracted, dried, refilled and made good with the household at home.²

£200k

Contract value

Called off under the council’s framework, priced home by home.³

28months

Programme length

December 2025 to March 2028 under the Housing and Neighbourhood Property Services Framework, programme reference EG060.⁴

Before and after

What extraction and refill actually involves.

Failed cavity fill does its damage out of sight. It slumps, it holds water, and the wall above it gets cold and damp while the tenant gets the blame for condensation. The fix is not more insulation on top. It is the old material out, the cavity clean and dry, and the wall refilled properly.

Illustration of a cavity wall with failed insulation, showing where damp collects and how the fill is extracted — The failed fill: slumped, wet at the base, cold above the damp line. Illustration, not a Kirklees property.

Diagram of a cavity wall refilled with blown insulation through drilled and made good injection points — The refill: the cavity cleared and dry, blown insulation to specification, drill points made good. Illustration.

The work

Out with the old fill, then the wall fixed at source.

Every home starts with a survey and a retrofit assessment: which walls have failed fill, where the damp is coming from, what the ventilation is doing, and what the household needs from us while we are there. Miles ran the programme end to end, from framework award to handover, and the resident liaison sits with the office team rather than with whoever happens to be on the van.

On site the sequence is fixed. Extract the failed fill through drilled points and check the cavity is clear. Deal with the cause: groundworks and a new damp proof course where rising damp is feeding the wall. Refill with Knauf Supafil 40 to the manufacturer’s specification, then the full ventilation measures so the drier home stays dry. Make good the drill points, the render and the internal finishes, and clear up.

It is all delivered to PAS 2035 and TrustMark requirements, which in practice means a named retrofit coordinator, a design for each property rather than a blanket specification, photographs at every stage, and a file at handover that the council can audit. Nothing here is fast, and none of it should be.

Blown cavity wall insulation being injected through a drilled point in an external wall. Illustrative image — Blown insulation going in through a drilled point. Illustrative image, not a Kirklees property.

The programme

A framework, a council landlord, and its stock.

The client is Kirklees Council’s Homes and Neighbourhoods service, the council’s own landlord for around 21,000 council homes across Kirklees.⁶ The work is called off under the council’s Housing and Neighbourhood Property Services Framework, programme reference EG060, with Tracey Wilcox as the client contact.⁴

Cavity wall extraction and refill is where a landlord finds out whether a contractor can be trusted in tenants’ homes. The job is dusty, it needs access to every elevation, and the household has to be told what is happening and when. Delivered by the team now at EnergyGiants, office based and on the tools, that is the part we would ask a council to check with the residents rather than with us.

Delivered under Kirklees Council’s Housing and Neighbourhood Property Services Framework.

Cavity wall insulation being installed in a brick wall. Illustrative image — Illustrative image. Photographs from the programme will follow.

What was delivered

The specification.

Client	Kirklees Council, Homes and Neighbourhoods. Client contact Tracey Wilcox
Programme	Cavity wall remediation across occupied council homes in Kirklees, Huddersfield and Dewsbury, West Yorkshire. Programme reference EG060
Framework	Kirklees Council Housing and Neighbourhood Property Services Framework
The package	Survey and retrofit assessment, resident liaison, extraction, refill, ventilation, groundworks and damp proof courses, making good and remedials
Measures	Cavity wall insulation (extract failed fill and refill), full ventilation measures, groundworks and new damp proof courses to tackle rising damp at source, making good
Materials	Knauf Supafil 40 blown insulation
Standards	Delivered to PAS 2035 and TrustMark requirements
Working conditions	Occupied council homes, residents at home throughout
Project lead	Miles Sharples, Managing Director, EnergyGiants¹
Dates	December 2025 to March 2028. 51 homes completed as at July 2026²

Step oneSurvey and assess
Every home surveyed and given its own retrofit assessment before anything is priced.
Step twoPrice and programme
Called off under the framework, sequenced street by street, residents told the dates in writing.
Step threeDeliver
Extract, dry, damp proof, refill, ventilate, make good. Photographed at every stage.
Step fourHand over and certify
The PAS 2035 file, the guarantee paperwork and the council’s sign off, home by home.

Take it with you

Download the case study (PDF)
Four pages: the programme, the delivery, the outcomes and how to reach us.

Download the case study (PDF)

Failed cavity fill in your stock? Talk to the people who have taken it out.

Councils and housing providers: extraction and refill is the measure that goes wrong in the wrong hands, in homes people are living in. The team that ran this programme is now at EnergyGiants. We survey and price home by home, deliver to PAS 2035, and hand over a file you can audit. We work on programmes for landlords and public bodies and on insulation of every kind.

Talk to us about a programme Ring 01200 407790

Notes on the figures

This programme was delivered under a contract held by a previous company. It appears here as the track record of Miles Sharples, who ran it end to end, and of the office team and workforce now at EnergyGiants. EnergyGiants was not the contracting party.
Homes completed: 51 as at July 2026, from the programme records. The programme continues to March 2028.
Contract value £200,000, from the programme documentation.
Framework, programme reference, dates and client contact are from the programme documentation: Kirklees Council Housing and Neighbourhood Property Services Framework, reference EG060, December 2025 to March 2028.
No energy, bill or carbon saving is stated on this page. Cavity wall insulation savings depend on the house type and the year, and any figure we publish later will carry its assumptions and cite the Energy Saving Trust method.
Kirklees Council facts: Homes and Neighbourhoods manages around 21,000 council homes across Kirklees, as published at kirklees.gov.uk, read 7 September 2026.
Photographs and diagrams on this page are illustrative and are not of Kirklees properties. Site photographs from the programme will replace them.

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