And a concept I tried to recreate at a board meeting 2 years ago.
You guys are going to learn a little bit about rain gutters and downspouts... sorry.
We were called out to clean out a bunch of rain gutters and downspouts at an association that is mostly 4-stories high. I dont like bidding on these due to safety reasons so I bid the job high and wouldn't you know... they signed it.
Sent the gutter cleaning crew over there and they cleaned out the gutters and downspouts. Next rain, I get a call saying my guys missed a bunch of the gutters, as they are all overflowing which is very loud when the water lands. Send the crew back out there, and everything is clean and free flowing. I explain this to the manager and ask for a history of this and if it's been an ongoing issue. She calls me back and said, "This has been happening since the buildinig was built, 20+ years ago."
Derp! This is something I would've liked to know ahead of time. "Sorry, Sam, this is a new HOA for us." Because of this, I need to go and inspect the gutter and downspout system to figure out why they are not working.
First thing I notice is that they have half-round gutters installed but no ribbed brackets to support the weight of the water in the gutter. These should be installed every 4' because, as you know, water weighs a lot. Because of this, all the gutters are leaning forward, some by quite a bit.
Even though they are leaning a lot, they should still be working... kind of. But something else struck me as WTF and that was the size of their downspouts. 2" round downspouts which is way, way to narrow.
The way a gutter system works is that there is a drop outlet that is cut through the bottom of the gutter, and slides down through the gutter, and inside of the downspout.
The drop outlet is typically 1.75" to 2" round and when you install a 2" round downspout to these drop outlet, it is a very tight fit. Too tight, in fact.
Some where so tight, you couldn't even see the drop outlet.
So I called 1 of my roofers and had him meet me there so I can run 2 tests. There was a nice 10' long gutter that was accessible from a 1-story ladder.
I had my guy cork off the drop outlet, and we flooded the rain gutter until it was overflowing. Once it begun to overflow, I had him remove the cork and at the same time, I started my stop watch. It took 1:47 seconds to drain that 10' gutter completely.
So we remove the preexisting 2" round downspout, and installed a 2" X 3" downspout to the drop outlet that was allowing air to flow through the system.
We flooded the gutter again, and ran the stop watch and the gutter drained in :34 seconds. Holy ****!
Explained this to the HOA board members and used the example of pouring your cooking oil into a nicer bottle through a cone, and how if there is no air between the cone and the bottle, it takes forever for the oil to drain, until you lift it up a bit to allow for air and spill oil all over the place.
Anyways, I provided them with a gutter and downspout replacement for their HOA and bid it really high because... I didn't want the job. Guess what? Yep, we just finished it 2 weeks ago. Removing and replacing the gutters was back breaking work but they had fun installing most of the downspouts, as they got to drive around in a bucket-lift.