Raining behind a window


Has anyone had rain fall behind an outside window? I have the idea to run a pvc pipe over the window backstage and drill holes in order to drip down. Also, I think some creative lighting back there will help out.

We don't have plumbing backstage; so I'm either going to have to run a hose from the front and under the stage, or get a fountain pump.

Any ideas or past experiences?


Active Member
well, when we did 10 lil indians, we had rain going down a window. we just ran a hose to a PVC pipe, had holes in the pipe, very small holes, and had large containers at the bottom which had pumps in them to get the water out. we covered the wood and windows in a sheet of plastic also to keep the water from getting on the wood.


Well-Known Member
At one point or another I looked into this and found quite a few pages arround the internet describing how to do this type of thing. I personally have never done this so I dont really have much insight other then what can be found elsewhere on the internet. (sorry i dont remember the URLs, i found them via google, and they can probably still be found that way)


Handy is the kind of portable electric submersible sump pump.

Build a trough slightly wider than the window, and slightly wider than the pvc rain pipe wider than the window.

Drill the holes on the top side of the pipe, the drops will fall more randomly.

Let the trough drain into a 5 gal bucket where you can submerge the pump. You can line the sides of the bucket with some soft foam rubber to absorb pump sound and sandwich another thick piece under a lid for the same purpose.

The pump is basically on or off only, so you have the option of putting a valve inline to regulate flow rate (you can also adjust scene to scene or mid scene if rain is supposed to be varying). You still may want to test the arrangement very early on to see that there are no water hammer effects from air/water interaction.

The good thing about the sump pump is that it better tolerates junk that may end up in the water.

A few things to watch out for:

The noise of the water falling onto whatver collection/protection system you use. You can protect the scenery and help drain the water back into the trough using plastic sheets (which will make some noise, though if done at an oblique angle actually provide a perfect rain sound effect). For almost no noise at all, low pile indoor-outdoor type carpet can be used instead, though with appropriate structure behind it.

Issue 2 is that plain water is hard to see. Highlighting with water is one out. Adding something to the water is another. Gene Kelly famously sang "Singing in the Rain" in milk, but don't do it, it will stink to high heaven within a day or so and not go away.

Also, if you have a door in the set that also opens to the "outside", it will look strange if you see rain out the window but not out the door. You can build a larger rain capture system, even covering the whole stage if you have to, but that's a step up in complication.


Active Member
I've read about these, but never had the occasion to try to use them. (It seems to me that water and a stage would not be a good combination.)

That being said, the pumped system described (as described by darkfield) would be better than one hooked up to the water supply – hoses joints/connections can leak, valves can leak, valves may not fully close, someone may not turn it off completely or tightly, the tripping hazard of the hose, water draining from the hose when you take it apart after each use, etc. With a pumped system, the amount of water is limited, and the water is contained in a limited area.

Remember to keep a dry mop or two backstage, maybe some paper towels, too. You may even want to consider keeping a supply of old towels or blankets, in case of a major spill. You'll also want to be able to dry the system out after each use, at the end of the day, to keep it from getting musty.

Good idea about watching for water hammer, particularly if its an oversized pump. You might need to consider putting in a check valve near the pump discharge. Or you may need to activate the pump against a nearly-closed valve and gradually open it. (But that may depend on the scene requirements and cues.)

[darkfield - Does the pump discharge line end at the pipe with the holes, or does the pipe continue back to the bucket, with a recirculating flow?]



jwl868 said:
I've read about these, but never had the occasion to try to use them. (It seems to me that water and a stage would not be a good combination.)

[darkfield - Does the pump discharge line end at the pipe with the holes, or does the pipe continue back to the bucket, with a recirculating flow?]


It's recirculating. (I guess it wouldn't have to be, but sure makes sense).

The outlet of the pump is a hose fitting and you just need to have a place to attach the hose (shortened scrap of it, as short as practical to allow handling the pump but avoid opportunity for trapping air) to the pvc. No reason you couldn't use steel pipe, either, but drilling is more of a hassle.

This scheme replaced an attempt with the hose that suffered greatly from water hammer issues. Much nicer to limit the amount of water that can get loose, and since the stage doesn't typically have a sink or other tap, the hose might have to be run in a way that creates additional headaches (doors that can't close, or hose needs to be removed every night).

I think the trough was built from plywood or 1x12, but lined with plastic sheeting, too. A sink drain type fitting about 1-1/2" or so ran out the low end, stuck out several inches, and went through a hole in the side of the 5 gallon bucket. The hole is in the upp half of the bucket. You have to have enough capacity in the bucket to hold the water in the system, obviously, since it will all drain back there when the power is off. Again we stuffed thick foam rubber around the area between hole and the drainpipe.

I can't remember all the details anymore, like did we suspend the pump so it didn't rest on the bottom and transmit nosie and vibration?

This was a small portable sump pump, not a big one. The kind that rests on the floor, with a screened base, and cord/hose connection on top.

The water wasn't a big issue. Plastic sheet on the back of the flats, on the floor, etc.

I am repeating myself, but the running water noise was very effective.

It was probably up and running as needed for a little over a week, never had a problem with the mustyness. If it's clean, it should be fine, and you could change it if necessary. I wish I knew what to add for visibility that wouldn't smell or cause other problems.

You don't need a huge amount. Despite that, I suppose it might be smart to consider issue like nearby floor pockets and so on that would be at risk in a worst case (trough tips over, piping come apart, bucket spills, somebody soaps the trough).


Umm well if you wanted a simpler and dryer option, try about 2 dozen 1/4" white ribbons tied in loops over two spinning drums (one at top of window, one at bottom) When the drums move the ribbon closest to the window moves down and voila, you have rain. If you want a classic example of this check out the tiki room in either Disneyland or Disney World.

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