[biohead]

Thanks for that.
From what I've done in the house, I think the main entry into the house runs straight into the loft. From there it goes to the master bedroom, then comes back out of there and into the living room - there isn't a central point to spur things from.
I didn't know if an engineer would use a splitter in the bedroom with a 2nd isolate, or something different (like create a central point).