How to advise without photos of the chamber ?

Forumers don't have microscopic eyes to look beyond your posting 😅

Try using waterproofing paint. I used Penten brand previously for my roof slab. There are various brands in the market, so study your preference.

When using such product, the wall must be dry and clean. U have to air the chamber for few days before applying the waterproofing.

To clean the wall, you require a pressure washer. Don't shoot the water near the wall, else u might break the cracked cement wall.

This post has been edited by mini orchard: Aug 15 2025, 09:39 AM