Yeah, it is hard to explain... I will put a piece of 50 x 200 across from the girder to the wall and "hang" the beams using these:
And hang the beam that they cut using this (it is cut further back from where I will hang the bigger beam):
I am boarding out the storage section of my loft and have seen that the loft conversion company has made the waste pipe fit by cutting a footlong chunk out of the floor joists leaving them only 3cm thick at that point.
The picture only shows one joist but of the four in that section they have...
