Gap in flooring what do I fill with?

[SteveMc]

I have removed the carpet from my parents house with the intention of installing Oak flooring. I came across this problem, the screed has crumbled and when removed discovered this insulation covering copper central heating pipe, obviously I like to fill it before installing floor but not sure what to fill with, do make another screed type mixture of use a pre-mixed flooring repair 'kit'?

Any advice would be appreciated, the house is 38 years old, it has a DPC and there is no sign of damp.

Thanks

 

[vinn]

Fill the gap with a semi-dry 4:1 sand and cement mix and smooth off with a trowel or a block of wood.

 

[SteveMc]

Thank you so much. It was what I was thinking, just need someone to confirm my thoughts.

Steve