One-day bathtubs are bathtubs that can be installed in just one day. This is possible because they come in pre–assembled sections that just need to be put together. This is in contrast to regular bathtubs, which need to be assembled on–site from scratch. One-day bathtubs are thus much faster and easier to install, and are therefore a popular choice for busy homeowners who want to avoid the hassle and delay of a traditional bathtub installation.