An expert has said he is "incredibly puzzled" as to why a prevention system that survived the first Glasgow School of Art blaze was ripped out before the second fire.

The world-renowned art school was extensively damaged last June while undergoing a £35m restoration following the previous fire in May 2014.

The Scottish Parliament's culture committee heard on Thursday from independent fire adviser Stephen Mackenzie.

Speaking about the mist suppression equipment, committee member Tavish Scott asked Mr Mackenzie: "The committee wasn't told it was removed after the first fire and we are all puzzled as to why it would have been removed. Why would it have been removed?"

Mr Mackenzie said: "I'm also puzzled as an expert."

Mr Scott then asked: "Do you think there would have been a good argument for retaining that system until such time as other things were developed, if that was your fire prevention proposal for the future?"

Mr Mackenzie replied: "Categorically I've stated there should have been a temporary or phased installation and that could've been part of that basis. I'm incredibly puzzled to now hear that this has occurred."

The art school said it was advised the system was unusable following the blaze.

The committee also heard that ventilation ducts which allowed the fire to take hold in 2014 were still in place at the time of last year's blaze.

They had been due to be rectified at the end of the restoration project.

Dawson Stelfox, a conservation architect at Consarc Design Group, told the committee: "It was planned to deal with the ducts as part of the works on completion so they would have been fire-stopped.

"But the missing bit seems to me to be measures to protect fire spread during the construction process and those ducts were not compartmented."

He added: "Fire-stopping during construction is not an easy thing because it might continually be disruptive and have to be put back into place.

"But I would suggest to you that there hasn't been enough focus on achieving compartmentation fire-stopping during the construction process."

MSPs were also told by Historic Environment Scotland that they could not offer any financial support for a new build of the Mackintosh building as grants are for the repair and conservation of existing historic fabric.

Referring to the mist suppression system, a Glasgow School of Art spokesman said: "As a result of the 2014 fire, considerable elements of the system were destroyed or damaged.

"The GSA sought expert advice which indicated that this system was unusable.

"As you would expect, the GSA wanted to take advantage of improvements in the technology and install the best system for the building.

"The installation time for the replacement system in the post-2014 restoration would have been broadly similar irrespective of the type of system commissioned."

Committee convener Joan McAlpine said findings and conclusions would be published in due course.