Levelling floors in Victorian house

Hi There, As a qualified chartered structural engineer, I can list the following typical issues as the main cause: shallow footings and foundations, heaving ground due to clay substrate, subsidence, lime mortar used for brick work, twisted and warped timber joists, rotten or woodworm set in the subfloor timbers.... None of them should scare you, as all these issues are expected to happen over the time given the age of the property and the methods of building at the time of construction. Solution! If after lifting floor boards, you see no sign of wet or dry rot in timbers, or no woodworm activity, and timber joists been only warped and twisted naturally, then you can use sistering techniques to level them correctly. Make sure you buy C24 structural grade timbers. But, if you detect any signs of rot or woodworm, I'm afraid you'll have to completely change the entire subfloor. Never sister new timber to rotten one, as it will only spread the rotten faster . Hope this helps, and good luck 👍

You may want to contact a structural engineer before doing any work as a precaution.