We were approached by a Dad on a mission to create the ultimate StarWars games room for his daughter.
After a discussion over email, we realised that there was space above the room where we could work from above to the original ceiling. So the client proceeded to decorate the ceiling prior to us arriving.
When we arrive we usually mark out the ceiling where the joists are and then sketch out metre squares too. Depending on the spec chosen we would then drill the holes and then fit the fibres from above, dressing fibres through joists so that loft boards can still be fitted and loft conversions are still possible etc.