Hello, firstly thank you for any advice, it is much appreciated! My question relates to my badly leaking concrete roof terrace. The property is over 100 years old and the previous owners chopped off the end of the roof to make themselves a large roof terrace. From my unprofessional view, it looks as though they attempted some sort of repair to the old concrete they must have laid to begin with by pouring another layer on top, but I cant be sure. This layer is breaking up badly and lets a lot of water through into the area beneath (not residential but will be eventually) as a temporary measure, I was told to pour water glass into the holes and cracks. My questions are: How do I prepare the surface before applying the water glass. Will the water glass cause a problem in relation to other materials being placed on it later on? How effective is water glass? and does it need to be mixed/diluted or anything or can I just chuck it on? The purpose is to find a temporary solution while other work is carried out which needs to be completed before we can begin the floor repairs/resurfacing because every time it rains I can almost feel the floor weakening! Thank you for any advice!