Owner’s consultant advises that joints must be sealed with silicone, fabricator advises using grout - who’s right (for precast concrete wrap, not structural elements).
Who’s going to hold the warranty?
Anon,
The Owner’s consultant.
We’ve always used the “belt and suspenders” approach by using sealant and backer rod over a precompressed joint sealer. I can’t recall ever having seen a project in our office where grout was used.
Sealant moves, grout doesn’t.
How about Epoxy grout?
Epoxy grout moves even less, and has a tenacious hold on the precast.
One question for you, is the precast being adhered to a plaster substrate? Or what is the assembly being proposed. The answer would depend on the condition being challenged.
The precast is being used to wrap a steel column, as a decorative element.
It depends on how the precast is attached. If it was hard attached to concrete in a shear wall building I might consider grout.
Typical methods of attaching precast to steel would allow enough movement that the grout would crack and allow moisture to get inside. Use sealant you will have fewer problems.
I definately would not use epoxy grout. This idea is based on the idea that you can restrain the building movement. Buildings move. You can influence where the cracks are but you cannot prevent them. The epoxy grout would cause the cracking to occur in the panels and not in the joint.