Water proofing render

Xcellor

I put my shed on a layer of concrete blocks and mortared in but I need to put a render on to stop water from coming through. Whats the best job for this? doesn't need to be perfect finish.

my3cents

Xcellor wrote: »

I put my shed on a layer of concrete blocks and mortared in but I need to put a render on to stop water from coming through. Whats the best job for this? doesn't need to be perfect finish.

Can you slip a jack under the shed joists so you can lift lift it enough to slide a piece of block work DPC under each one?

I have block work under several sheds and water coming through isn't really a problem provided there is a DPC under the wood shed parts.

Xcellor

my3cents wrote: »

Can you slip a jack under the shed joists so you can lift lift it enough to slide a piece of block work DPC under each one?

I have block work under several sheds and water coming through isn't really a problem provided there is a DPC under the wood shed parts.

Unfortunately the shed doesn't have a lot of height in it, only realized after purchase. So the concrete blocks were put to increase the height. If I put a floor inside it with DPM i'll lose the extra height gained from the blocks. The slab that i poured has a DPM under it to stop water coming up. I could have put another row of blocks but this project is running over in terms of time taken and the OH is fit to kill me

I was thinking of just putting some external render mixed with with evoplast around the external blocks making sure to move water away from the base. Water isn't flooding in or anything as I've good drainage both sides. I could even finish with some masonary external paint?

my3cents

Does the shed have a floor built in or are you relying on the slab as a base?

Xcellor

my3cents wrote: »

Does the shed have a floor built in or are you relying on the slab as a base?

Yeah exactly the slab is the base and the metal shed is mounted on row of concrete blocks

my3cents

Xcellor wrote: »

Yeah exactly the slab is the base and the metal shed is mounted on row of concrete blocks

Sorry, wood sheds are my thing and don't have a clue about render. Well know enough to say I can do it but hate it.

By row of block I assume they are laid and jointed and you have a dpc between the shed walls and the blocks?

If thats the case then I don't see a need for any special render. In fact any render may bridge that gap between the dry slab and the soil?

Xcellor

my3cents wrote: »

Sorry, wood sheds are my thing and don't have a clue about render. Well know enough to say I can do it but hate it.

By row of block I assume they are laid and jointed and you have a dpc between the shed walls and the blocks?

If thats the case then I don't see a need for any special render. In fact any render may bridge that gap between the dry slab and the soil?

Im attaching a rough sketch. The blocks are mortared onto the slab. I know I need to tidy up the joint work and this looks like where water is coming in. So for the render I was considering adding this when I render
https://www.mcmahons.ie/evoplast-waterproofer-plasticiser-5l

As the blocks by themselves will just soak water through.

my3cents

Everything is above the DPC so you'll find the blocks will dry out just as quickly as they get wet but no harm in your render and that plasticiser will help. If you are really worried about it once the render is fully dried out you can give it a coat of silicon waterproofer https://www.mcmahons.ie/thompsons-one-coat-water-seal-5l .

Xcellor

my3cents wrote: »

Everything is above the DPC so you'll find the blocks will dry out just as quickly as they get wet but no harm in your render and that plasticiser will help. If you are really worried about it once the render is fully dried out you can give it a coat of silicon waterproofer https://www.mcmahons.ie/thompsons-one-coat-water-seal-5l .

Thanks I will render and see how that improves things and if its still not great ill try the silicon water proofer.

Cheers.

Stoner

Xcellor wrote:

Thanks I will render and see how that improves things and if its still not great ill try the silicon water proofer.

You can inject a chemical into the blocks to form a barrier to water rising up.

However I agree with the above that they should dry out by themselves.

I have the application gun for that somewhere if you want to borrow it, bought it years ago for an issue I had at home.