A growing trend of fire door problems at the point of building handover is a cause for concern, according to Chiltern International Fire (CIF).

The testing organisation said the problem may be due to the many new entrants to the fire door sector not fully understanding the scope of their product’s test evidence or assessment.

This has resulted in companies incurring the additional cost of having to run further tests simulating on site conditions.

CIF said it had seen a “significant” increase in the number of cases where Building Control had picked up problems with fire doors.

“Variation on configuration, species or glazing may not be allowed unless they have been specifically tested or appraised and some newer manufacturers may not fully appreciate this,” said Mark Cummings, CIF’s head of section: fire resistance.

“It is important that manufacturers understand that even a simple change of hardware can invalidate the test result.”

CIF said joining a third-party certification scheme was one way to alleviate the daunting task of understanding the scope of test evidence.