The alert was first raised when defective ACM cladding was removed following the Grenfell disaster at one major scheme in Croydon.
The frame of the Citiscape residential high-rise in the town centre had suffered large structural cracks prompting the immediate evacuation of residents from the first two floors.
Now further investigations of buildings designed for Barratt by the same original engineering firm or by other companies within the group have unearthed issues at seven more buildings, although not as serious as those found in Croydon.
Barratt said it now faces a £70m bill to cover the cost of remediating all buildings, up from the initial £2m estimate to cover recladding the Croydon building alone.
The house builder said it was now actively seeking to recover costs from third parties.
In a statement this morning Barratt said: “As a responsible developer, we appointed independent structural engineers to review all of the other developments where RCFs were designed for us by either the same original engineering firm or by other companies within the group of companies which has since acquired it.
‘The preliminary reviews of all 26 of these developments, the majority of which were designed over 10 years ago, are complete and have not identified any issues as severe as those present at Citiscape.
“Engineers are now undertaking more detailed reviews to see if any remediation of the concrete frames is required.
“Those detailed reviews have so far shown that eight developments have no defects while seven developments required some remedial action to address smaller-scale problems.
“At these developments, remedial action has either been successfully completed or is underway.
“While in most cases we have no legal liability, in line with our commitment to put our customers first we will ensure that no costs associated with remedial works are borne by leaseholders.”