Week 54-55 - Tanking

Tanking? Yea I think it’s a weird name too! It is basically waterproofing the wall (and/or slab) of a building to make it water tight against ground or flood water. In the same way as a fish tank or petrol tank is, so you can kind of see where the name comes from. But those things are designed specifically to keep water in, whereas we’re trying to keep it out – so really it should be called inverse tanking (no?). Anyway, stupid name, let’s move on…

In simple terms all we are really doing is spraying, rendering, painting, spraying again, painting again etc etc the downstairs walls of the building with a vast array of expensive chemicals, pastes, renders, emulsifiers and anti-sulphates. Most of which I only have a very vague understanding of how or why they make it water proof, but I am assured they do. If you are interested there are lots of websites that explain very well, I’ll leave you to educate yourself in your own time – its as dull as you’d imagine.

First I had to build new inner block work skins the the two side walls of the building. This is because the tanking needs a smooth even surface with no cracks to adhere to. The old stone walls are none of these things and have cracks and gaps a whole families of borrowers could live in. I admit I am far to proud of these two walls for what they are! But I had never done any block or brick laying before this project and always wanted to. I have definitely seen a good improvement in my skills since the first blocks I laid at the beginning of the build. 

Above you can see the first coat of the K11 slurry going on to the right hand side and prepared area for coating with all other chemicals applied to the left.

Finished river wall now waterproof up to just above window level

The middles stone wall of the building was rendered first before coating rather than blocks as the sides. As it is internal and only needs to withstand water pushing up from below not direct attack.

And finally the concrete floor around the main entrance, the only part of the old floor that was not covered by the new waterproof concrete floor was also tanked.