Sealord Group, based in New Zealand is the country’s largest supplier of processed seafood and
exports to more than 60 countries worldwide selling more than $400 million worth of seafood.
The main freezer floor in the hold of the FV Rehua needed repair. The floor is concrete over polystyrene;
the freezer operates at –30°C and the polystyrene acts as the insulation. When the ship off-loads
its catch, the freezer room is washed down and when the ship goes back to sea the room is back
operating, this constant freeze-thaw cycle caused the floor to spall. The concern of water working its
way down into the insulation and holding water would lead to major issues later on, replacing this type
of floor is a major cost.
Initially the team was looking at an epoxy coating (the generally accepted method for similar situations)
but after discussion with Fraser Brown & Stratmore Limited, Kryton’s Krystol Concrete Waterproofing
products were selected for the job.
Kryton’s Krystol T1 and T2 Waterproofing System were selected over an epoxy coating because it has the ability to self-seal
small cracks, it penetrates deep into the concrete and the waterproofing properties are not affected
by surface wear or abrasion.
The floor was prepared by grinding, removing sealant from the joints and then washing to remove any
oils etc. The surface was then brought to SSD condition and the first coat of T1 was applied. Due to
the location at the bottom of the ship there was not a lot of air movement so a fan was used to move
the air around in the hold overnight to harden the T1 layer without it drying it out too fast.