Cladding specialist Sto Ltd was named in five High Court cases centring on historic installations of its StoTherm Classic system before entering administration, Construction News research has found.

CN identified the cases in High Court records after administrators at Grant Thornton reported receiving £135.2m of unsecured claims against Sto Ltd, largely comprising contingent claims relating to legacy cladding issues.

In their update report, administrators did not identify the claimants or projects behind the £135.2m, or say whether any of the court cases are included in it.

But court documents inspected by CN show that Sto Ltd was named in five cases at the Technology and Construction Court linked to stated remediation costs, pleaded claims and underlying judgment sums exceeding £100m.

Four of the cases remain unresolved, while the court ordered Sto Ltd’s German parent to pay £1.77m following a default judgment in the fifth case.

All five concern historic, project-specific installations or configurations of StoTherm Classic, including systems identified in the papers as Classic K and Classic M, as well as adhesive-fixed and mechanically fixed systems.

Four of the claims were issued in December 2024, the month before administrators were called in.

The cases do not concern or determine the safety of any system currently marketed by the Sto group companies.

Administration moratorium rules prevent proceedings against Sto Ltd from continuing without the administrators’ consent or the court’s permission.

However, proceedings against other Sto group companies have continued in some of the cases.

The claims against Sto Ltd

Before Christmas 2024, Lendlease Residential (CG) Ltd and Lendlease Residential (BH) Ltd lodged a £21.1m claimconcerning five buildings – four at Clarence Dock in Leeds and one at Capricorn Place in Bristol, completed between 2003 and 2007. The Lendlease companies allege that Sto Ltd and/or its German parent, Sto SE & Co KGaA, made misleading claims about the performance of the historic StoTherm Classic systems installed on the buildings. They also allege that the systems were inherently defective or failed to meet construction-product requirements. The allegations have not been determined. Court records show that no substantive defence had been lodged in the Lendlease case by an April deadline set by the court.

Companies in the Redrow group – HB (WM) Ltd, Redrow Homes Ltd and Redrow Ltd – filed a separate claim in December 2024 concerning the StoTherm Classic system installed at the Hemisphere development in Edgbaston, Birmingham, which completed around 2008. The remediation works were estimated to cost £27.3m, but the companies acknowledged that some of the work did not relate to the StoTherm Classic system and would be excluded from their claim.

Also in December 2024, Barratt Redrow, BDW Trading and Barratt London provisionally valued a claim concerning historic StoTherm Classic installations at five London residential developments, completed between 2000 and 2006, at £47.6m. The developments are Pierhead Lock, Tower 8 at Barrier Point, Tideslea Path, Switch House and Centreway Apartments. The claim documents describe several configurations, including Classic M and adhesive-fixed and mechanically fixed systems.

All three proceedings also name Sto Ltd’s German parent, Sto SE & Co KGaA, and Sto SE’s ultimate parent, Stotmeister Beteiligungs GmbH, as defendants.

In May, the High Court rejected the German defendants’ argument that the claims against them should not be heard in England and Wales, allowing those claims to continue.

The ruling did not determine liability for the alleged defects or remediation costs.

Sto Ltd was also named in two cases brought by contractor Mulalley & Co.

The first, filed in March 2024, concerns StoTherm Classic K installed on four tower blocks in Gosport, Hampshire between 2007 and 2008. Mulalley is seeking a contribution after an earlier judgment required it to pay £10.8m in damages, interest and costs to housing association Martlet Homes. Mulalley wants Sto Ltd to pay a share of the £10.8m, but has asked the court to decide how much.

The second Mulalley case was also filed in December 2024 and centres on StoTherm Classic K installed during the 2007/08 refurbishment of Parkside Court, a residential tower block in Chelmsford. After Sto Ltd entered administration, Mulalley continued its case against Sto SE & Co KGaA, Sto Ltd’s German parent. Sto SE did not defend the claim, and judgment was entered against it by default. In June, the High Court ordered it to pay Mulalley £1.77m plus interest under a building liability order, as well as £175,000 towards Mulalley’s costs. Mr Justice Pepperall described the system installed at Parkside as an “unsafe external cladding system” and said the liability established by default included that it was inherently defective and had made the apartments unfit to live in.

Watkin Jones & Son Ltd also lodged a claim against Sto Ltd in 2025 – after the firm had entered administration. The court listing reviewed by CN did not disclose the claim value, project or any product involved in this case.

A statement provided to CN by Sto SE & Co. KGaA said: “Sto Ltd. always was a separate legal entity from Sto SE & Co. KGaA, and all decisions by the company were made by the former management of Sto Ltd.

“As to the Parkside Court case, we are aware of the ruling and are currently reviewing it.”

Administrators’ approach to Sto Ltd

The five pre-administration cases could help to explain the scale of the contingent cladding claims reported by

But the administrators’ report does not link any of the proceedings to the £135.2m in claims they said they have received.

Under administration moratorium rules, proceedings against Sto Ltd could be resumed if the administrators consent or the court grants permission.

In their latest progress report, the firm’s administrators said they would “continue Sto Ltd’s defence to proceedings either intimated or commenced over historical cladding supplies…as far as they believe appropriate…”

They said they would weigh the cost of continuing a defence against the potential detriment to creditors of abandoning it.

Work undertaken by te administrators during the latest reporting period consisted of reviewing Sto Ltd’s records for historical cladding information, they added.

Grant Thornton expects some money to be available for unsecured creditors but said the timing and value of any dividend remain unknown because of the continuing legal claims.

The administration is expected to be converted into a creditors’ voluntary liquidation within six months, with any distribution to unsecured creditors made during the liquidation.

Grant Thornton said: “We have received unsecured claims totalling £135.15m.

“We highlight that this is largely made up of contingent claims that are in relation to the cladding claims. These have not been adjudicated or confirmed as final claims in the administration.”

This storyis based on original court documents provided by litigation analytics firm Solomonic

https://www.constructionnews.co.uk/buildings/building-safety/firm-hit-with-100m-in-cladding-court-claims-before-collapse-13-08-2026/