Here's today's final updates. I've installed a vent at floor level on the south side and an extraction fan at the top corner on the opposite side, powered by a 12V 5W solar panel. The floor is all covered in foam mats which is a lot easier on the knees when crawling around.
Cheers Dave. I'm pleased with how it has worked out. It was a lot more work than I had anticipated but it is nice to not have to drag the gear in and out of the house
looks good Peter. I have likewise just received the OK from SHMBO for a similar build for my b'day next week. As always your work looks very well thought out and professional.
Peter,
I may be too late if you have already used expanding foam for the floor/wall join sealant. The stuff is not impervious, I suffered from this. See my thread
"a cautionary tale" in this diy obs forum.
Chris
The inside height of the Colourbond channel is higher than the outside height so in theory the water should drain outside before it overflows inside. The point of the foam was mainly to keep ants at bay.
I've sealed the gap between the bottom channel and the floor with exterior flexible silicone sealant:
Since completing that the only issue I still have is some moisture tracking up through the slab, despite two layers of impervious plastic underneath. It currently isn't causing grief however I have considered applying some concrete sealant.
Peter,
I found that my 100mm floor also leaks despite the underlay of plastic. I do find that an overlay of the same underlay plastic keeps the interlocking foam floor tiles dry and the trapped water exits via the cast in floor drains. Like you I will apply sealant, what do you intend to use?
Chris
Chris, I haven't looked into sealants for the concrete yet but I suspect there are plenty of suitable options to choose from. Have you found something?
As it turned out the roof on mine was easy to seal - just a blob of silicon on each screw hole.
Took me a lot more goes to get the walls sealed up. Because I've got a wood base, I wanted to seal the gap between the channel and the wood base, to prevent hidden water and rotting. However, this helped keep the water in.
Then when sealing the outside of the channel, even a small leak inside would just store water up until it leaked everywhere inside. More and more silicon eventually solved the problem, though it seemed to get worse before it got better. The door was a particular problem.
I've tried to keep the inside reasonably silicon free, since it at least lets you see if there is any water ingress, rather than hiding it away where things rust and rot.
