Are there any recommendations for the use of PROMASEAL® Fire Compound Extra Strength to fill a large opening ?

The Fire Compound Extra strength should always be installed in a single pour (i.e. seal filled by multiple mixes and pours but with none of the layers being allowed to set) as otherwise the seal would be made up of multiple “layers”, which would significantly reduce the strength of the finished seal). 

From start to finish, the seal should be completely filled within 40 to 50 minutes. 

For larger openings, where it would be difficult to install the complete seal within this time frame, we would recommend that the opening should be split into smaller, more manageable sections, using mineral fibre board upstands to create the smaller sections. The left section and right sections of the opening (sections 1 & 2 in diagram below) can be poured together and then left for a minimum of 2 hours before removing the upstands and then pouring the centre section.   Go to product information