Maybe I missed something,
You might have. Sometimes posts cross.
I answered these before, but I appreciate your help very much, so here are the summaries again.
but how are you going to resolve this? You've got a bamboo cross member at the low end of the roof, and water is pooling in the plastic.
Yes, sorry if I was not clear enough!
The father-son team is coming tomorrow to finish the greenhouse. (It is NOT finished yet!)
They plan to stretch the plastic, and attach it to the frame so that it will hypothetically drain into the gutter.
If it still pools after that (which it may), I plan to poke holes in the plastic, and have rainwater catchment under the pools, inside the greenhouse.
(WIth SIPs I am sure I will need lots of de-chlorinated water!
)
If you had no cross member, and the tarp was tight enough, the pooling wouldn't happen.
Right!
I think the issue is that in this particular location, we have to have a water channel, to make the water go down the drain tube (by community policy).
When we get to the property we can make greenhouses without the water channel.
I think he tried to copycat valley greenhouses, and then tried to adapt with a water channel.
If it pools, I will poke holes in the plastic and enjoy the rainwater!
As this is currently built, you've got two things working against each other: 1) the need to tighten the plastic and fasten it to the frame,
Should happen tomorrow, Father willing.
2) the need to catch and drain the water.
Yes.
As mentioned, that is why he is putting a rainwater channel on the outside of the structure, is to make the water go down the drain pipe, in accordance with community policy. .
I'm concerned you will not be able to tighten the plastic enough laterally. If any water begins to pool, and you have a strong enough rain, the pool will grow because of its weight, stretching the plastic, and then the feedback loop could end in disaster – water is very heavy (8.3 lb per gal). When these situations happen (i.e. design failure), if you catch it soon enough, you can poke a hole in the bottom of the pool to let it drain.
Yes, if he comes and goes and it still pools, I will be 100% fine with placing a rainwater catch-basin under any pools in the tarp, and using the rainwater in the SIPs, since this is only a temporary (planned one year) structure.
Compare to the below design... Each rafter is supported at the low end by a vertical member. There's no cross member at the low end, hence water flows freely. Note, you could potentially put a gutter on this design, especially if there was an overhang.
Thank you!
I will be sure to mention it to him.