The inspectors called for improvement across a whole range of fields including quality of education, leadership and management and apprenticeships.
The latest ranking comes as CITB has changed its business model since the last “outstanding” rating in 2017.
The CITB has moved away from the use of subcontractors to provide training to work closer with employers to recruit and train apprentices.
The move has seen the number of apprentices trained directly by the CITB drop to 629 from 9,000 at the time of the last Ofsted inspection.
A Spokesperson for CITB said: “These two inspections were not comparing like with like.
“CITB’s business model for supporting the sector to recruit and train apprentices fundamentally changed between the 2017 inspection and 2023.
“In 2017, CITB worked with subcontractors to deliver a wide range of apprenticeship training, which meant that when we were inspected by Ofsted we were responsible for a significantly higher proportion of all construction apprentices than we are today.
“From 2021 onwards, in line with Government policy, we made a strategic decision to move away from that model. CITB now works more widely with employers and providers nationally on the delivery of apprenticeship provision locally.
“Instead of subcontracting, CITB now offers support to employers and providers to recruit and retain apprentices through the New Entrant team. This was established in 2022.
“The New Entrant team approach means we can offer more comprehensive support to all construction employers who take on apprentices, regardless of the provider they choose to work with. We only continue to provide training directly in niche areas that would be prohibitively expensive for the rest of the market to provide for.
“Overall, this strategic shift has been a success. In 2017 there were 48,240 enrolments into construction apprenticeships in England, according to the Department for Education, whereas this year the enrolment number so far is for 58,970, a real improvement.
“We know there is more work to be done and we are focussed on listening to employers and further transforming our approach in order to meet the skills needs of the industry. There are no plans for future reductions in our direct provision.”