This is the 11048th most frequent Russian word.
гидроизоляции
Waterproofing.
Here, 'гидроизоляция' is used as a noun to describe a material or process used for waterproofing a structure.
Гидроизоляция необходима для защиты фундамента от влаги.
Waterproofing is necessary to protect the foundation from moisture.
In this sentence, 'гидроизоляции' is in the dative case, showing purpose or benefit.
При строительстве дома следует уделить внимание гидроизоляции стен.
When building a house, attention should be paid to the waterproofing of the walls.
Here, 'гидроизоляции' is in the genitive case, indicating possession or association, referring to the process or state related to waterproofing.