Barrier coat or not?

I’ve been talking to different shops about bottom painting our R27. Some recommend a couple coats of barrier paint before the ablative anti-fouling layers and others tell me they’ve seen more problems with barrier coat blistering than hulls without the sealer. Can anyone share their experiences with barrier coat vs just the biocide layer on the (sanded) gelcoat? Thanks!

I have never heard anyone say you could skip barrier coat. I know some shops don't like to take those jobs because of the timing requirements. The re-coat times can be critical.

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