Can you specify when caulk should be used with this floor? Does it need to be caulked around the expansion joint under the baseboards? Where else should caulk be used?

Hello Hannah - thank you for your inquiry. The use of caulk is more of a personal preference and finishing your flooring project. No - no need to use caulk under the baseboards. We recommend the flooring planks be free to expand and contract. (Some flooring manufacturers recommend the use of caulk cord and a silicon caulk to "perimeter seal" the floor.) And technically, you don't even need to caulk around a toilet when installing in a bathroom. (If caulk is used around a toilet, you wouldn't know if you had a leak or not...) The only time I personally use caulk when installing LVP / LVT is after I install my quarter-round. I will caulk any gaps between the quarter-round and baseboard. Hope this helps - Thank You!