# Forum Home Renovation Waterproofing  Waterproofing External Wall Foundations

## laan

Hi, 
I just removed the formwork for my shed concrete foundations... next up is waterproofing the walls. Here's a few pictures to show the situation:   
The shed is on a bit of a slope, so parts of the walls will be below ground level, and I want to apply some kind of waterproofing membrane to reduce the likelihood of dampness getting onto the shed floor. There will be drainage all around, but it might not be able to drain fast enough during a heavy downpour. 
I've looked into the options for waterproofing membranes and browsed this thread for any previous advice, but haven't found much up to date info for my particular situation. There's a pretty wide range of stuff out there to choose among, from a 20L bucket of Bondall Bitumen Rubber for $107, to a 15L bucket of K10 for $219 (which probably also needs a primer). 
There's also Duram Durabit Reo ($115 or so for 15L) which looks good, but also claims to need an expensive primer which makes is a lot more expensive than a bucket of bitumen. 
Any advice on what my best option is would be great.

----------


## Random Username

I'd be happy with a coat or two of bitumen followed by a sheet of black coreflute (at about $12 for a 2400x1200 sheet it's cheap insurance against rocks).  Or if you reckon you'll have some black plastic spare, bitumen, black plastic, then coreflute.

----------


## laan

Thanks Random, I'll just slap on some bitumen then. I'll be backfilling with sharp crushed up concrete rubble and knew I needed something to protect the waterproofing, but I didn't know what to look for. Coreflute looks perfect, cheers. 
Btw, I didn't have time to find a small enough vibrator and had to make do with shovels and sticks to make the concrete flow out properly... looks mostly ok but there's a few spots with trapped air bubbles on the sides. I have a feeling that trying to patch them up with just a plain mix of cement+sand wont work that well for a number of reasons, such as it wont stick very well and that too much water will be sucked out from the new filler into the surrounding dry concrete and make it brittle. I'm thinking of using Gripset Betta Concrete Crack Filler to fill up the little bubble holes fore putting on the bitumen, unless someone has a better suggestion?

----------


## Random Username

I'd just glug them up with bitumen, or if you must, plaster/spakfiller.

----------

