Levelling sloping bathroom floor
I'm in the process of renovating a late-19th century terrace cottage. Whilst stable now the property has experience some slight movement in the past. This has resulted in the floor of the upstairs bathroom sloping down towards one corner of the room.
I want to level the floor before tiling it, but am unsure as to how a go about this. The only option I have come up with so far is to try to affix a series of tapered strips of wood to the top of the floor joists so that they become level. However, I envisage producing the correct taper will be extremely problematic.
Any help/ideas would be much appreciated.