The housing giant has also appointed a Group Construction Champion to establish “the Persimmon Way” which will consolidate new home construction standards and embed best practice across the company.
The moves follow criticism of build quality by new homeowners.
Chief executive Dave Jenkinson said: “The group has invested in its work in progress and delayed sales releases on sites with higher demand to allow build progress to reach a more advanced stage.
“This supports the improvement in construction quality that we are determined to deliver, ensuring that our quality assurance processes are more effective for each home.
“We have invested significantly in digital technology covering our build and inspection processes and have recruited a team of Independent Quality Inspectors to critically assess each key stage of our construction process and to provide increased levels of quality and safety assurance.
“These enhanced quality assurance procedures are reinforcing the behavioural change required to mitigate the risk of substandard execution of the group’s required build processes, such as the historic failure to properly install cavity barriers in certain of its properties, from occurring in the future.
“We are continuing to progress our cavity barrier inspection programme, with over 20,000 properties now inspected.”
Results for the year to December 31 2019 show Persimmon made a pre tax profit of £1,041m compared to £1,091m last time on turnover down to £3.65bn from £3.74bn.