Foundation not level

[diydad888]

Hi,

Been working my extension project and have got my strip foundations in, thought we had got the top level but after seeing rain in the trench I could see one end of a 5 m stretch was about 50mm lower than other side, there are a few low areas but the 50 mm was the lowest.
these low areas can ne ober a couple of metres.
What is best to do now?
should I fill with water to level then add ready mix bags?
or can it be taken up by the initial mortar?

Thanks

 

[jeds]

You might be able to gauge up with mortar - depending on number of courses. I wouldn't go more than 15mm20mm joints though. If you don't have enough courses to play with cut a course of blocks.