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120 Minute Durasteel Fire Rated Ductwork

120 Minute Durasteel Fire Rated Ductwork

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Contact Fraser Shearer Sarun Vysakham Ben Tan Azim Rizvi Anand Raghavan Our USA Office

Home Technical Data Fire Rated Ductwork 120 Minute Durasteel Fire Rated Ductwork

120 Minute Durasteel Fire Rated Ductwork

The SMT system is formed by fixing 9.5mm, DURASTEEL® sheets on to a welded or cleated, prefabricated steel skeletal framework, minimum 3mm thick. The sheets are fixed using self-drilling self-tapping screws, with PROMASEAL® mastic applied before fixing to the frame. Flanged lengths of ductwork are bolted together trapping the PROMASEAL® mastic between the mating flanges. The SMT system can be constructed in 1, 2, 3 or 4 sided configurations.


Ductwork Insulation Matrix

Natural Ventilation / Powered Ventilation / Smoke extract
Minutes Stability Integrity Rock Wool Insulation
Type A or B duct – 300°C smoke temperature Type A duct – 1000°C+ Type B duct -1000°C
30 Yes Yes SMT SMT SMT
60 Yes Yes SMT SMT + 30mm of 60 kg/m³ SMT + 50mm of 60 kg/m³
120 Yes Yes SMT SMT + 50mm of 60 kg/m³ SMT + 80mm of 140 kg/m³




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SpecUp - System Specification Wizard

Answer the 5 short questions below to receive your recommended Durasteel system specifications. Hover over the ? icons for a brief explanation.

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Fire rating required?

Question 3/5

Fire integrity-only or integrity and insulation?

Question 4/5

Fire attack risk from one side or both sides of the system?

Question 5/5

Blast rating required in addition to fire rating?

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