I am sorry, however there is no such option for Tiling in Lightroom.
I like this answer and will look into it. I have found free applications
on the web, but thought LR 6 came with this option.
The free Adobe Reader 11 has tiling capability: Print posters and banners | Adobe Acrobat, Reader
It is possible to output a high-quality, full-size image PDF file using the LR Slideshow module and then print using Adobe Reader 11 in Poster mode.
If you need help let me know.