29 replies to this topic

[PaulEK]

I'm nearly finished with the roll-off roof observatory I'm building with my local school district, and could use some help.

 

We really should be having snow right now, but the warm weather has meant all the moisture has been rain. I went out to the site yesterday and found that some of it had ridden the rails into the building and dripped down the walls. Quite a bit, actually. Some may even have done some kind of wicking along the interface between the top of the the wooden plate (made of two treated 2x6s) and the bottom of the 1/4-inch steel plate above it.

 

One of the rails has its casters riding on inverted angle iron, and the other has them riding on the flat steel plate. More water comes in on the angle iron side. I'm not sure if that's because the hole the water comes in through is larger, or if that's where the prevailing wind comes from.

 

I built a sort of dam with caulk on the flat steel, hoping that would keep the water out, and it seemed to until this steady, long-lasting rain event we just had.

 

I'm not sure just how to seal things up better on the roof ends where the rail leaves the building, and would be grateful for any advice others with experience might have. Images would be especially helpful.

[GeneralT001]

I'm nearly finished with the roll-off roof observatory I'm building with my local school district, and could use some help.
 
We really should be having snow right now, but the warm weather has meant all the moisture has been rain. I went out to the site yesterday and found that some of it had ridden the rails into the building and dripped down the walls. Quite a bit, actually. Some may even have done some kind of wicking along the interface between the top of the the wooden plate (made of two treated 2x6s) and the bottom of the 1/4-inch steel plate above it.
 
One of the rails has its casters riding on inverted angle iron, and the other has them riding on the flat steel plate. More water comes in on the angle iron side. I'm not sure if that's because the hole the water comes in through is larger, or if that's where the prevailing wind comes from.
 
I built a sort of dam with caulk on the flat steel, hoping that would keep the water out, and it seemed to until this steady, long-lasting rain event we just had.
 
I'm not sure just how to seal things up better on the roof ends where the rail leaves the building, and would be grateful for any advice others with experience might have. Images would be especially helpful.

I am following this with interest as I have this same concern for the rainy area I live in. I haven't built to that point yet and would like to be able to incorporate some ideas to avoid rain seeping in along the tracks.

[44ye]

If you could post a picture of the system it would help

[PaulEK]

I'll try to get a good picture, but it may be a few days before I can (this weekend) and I was hoping, by that time,to apply the fix that someone gives me here!

 

Here is a highly cropped image taken before there was a piece of wood placed on the open space visible. The wood obviously does not completely seal the hole. Sorry the image is not better, but it's the best I have at the moment.

 

[JJK]

One way to eliminate rain penetration is to have the exterior beams that carry the roof slightly below level.  Of course, that'd make it a little harder to close the roof.

[44ye]

It would appear from the amount of light that you don't have any sort of soffit on either the gable or behind the facia  see link

 

 https://www.google.c...450481075556809

 

 

depending on what  you have on hand  you could place rubber wipers on the gable end made from inner tube or conveyor belt

 that would seal tight to rails

[PaulEK]

Thanks for the responses!

 

The roof is already as heavy as can be moved without some kind of power, and I'd like to avoid that. and since it's already built, changing the level would be pretty difficult.

 

Since that photo was taken, much of the end has been covered, but it is not a straight shot that could be covered by simply putting rubber windshield wipers on it. But I could be wrong about that, and will look it over carefully with that in mind as a possibility.

 

Does anyone have any photos, or links to photos, that might show how others have dealt with this? Even if I figure something out, I think it would be helpful for anyone else, like GeneralT001 in comment #2, who might find this thread.

[Kellogg]

I had a similar problem, and solved it by using silicone sealer along the edge where the angle iron meets the wood frame, as the rain seemed to be wicking along. I also sealed any holes i'd drilled in the angle iron but hadn't filled with a screw and also every 12" or so I made a small wall of silicon to funnel any rain over the edge of the wood.

 

After all this some rain was still getting in on the underside of the rails, so one final thing I did was to place a small 3D printed wall (for want of a better word) on the underside near the building as a final barrier forcing the rain down to the ground.

 

If this is hard to visualize let me know and i'll try to take some pictures over the weekend.

[PaulEK]

I think I get it, but some photos would certainly help. I don't have access to a 3D printer, but am pretty good at scrounging for other materials.

 

I'm going out to the site today to take some photos of my own, and to take some measurements. When we do finally get snow and ice here, I'm going to want to have the rails covered with something. I'm thinking of inverted rain gutters on hinges. We can just flip them over before rolling off the roof.

[HunterofPhotons]

One solution.

The brushes are attached to the movable gable end (note how the beam tops are chamfered to shed water):

 

 

 

dan k.

[Lorence]

When we do finally get snow and ice here, I'm going to want to have the rails covered with something. I'm thinking of inverted rain gutters on hinges. We can just flip them over before rolling off the roof.

 

Rail covers solve a few problems. See my site at the link below. All you need is a bit of gravity.

[PaulEK]

dan: chamfered rails would have been a good idea, but it's too late now! 1/4-inch steel plate, 5-1/2 inches wide.

 

Lorence: the rail covers on your observatory are an ingenious idea that is beyond anything that would have occurred to me. Again, it's too late on the building we have.

 

Ours was built by students in our high school's constructions trades class. They did fine work, but my planning suggestions, even some of my planning demands, were sometimes ignored by the adults in charge. The building was made in such a way that the walls ended up higher than I was willing to accept, for no good reason other than the convenience of the person overseeing it. Another teacher did his best to lower it, but only after the roof was already on, so he could not easily get into the corners to make the rail end of the building easy to seal.

 

Here's a shot I took today, showing the side with angle iron from inside the building.

 

[PaulEK]

Here's the same spot, shown from a different angle.

 

[PaulEK]

And now I've highlighted the chunk of wood that is really in the way of easily covering the end with some kind of seal. I know it's probably difficult to understand from the image just what is going on, but it just sticks right into the way like it enjoys causing me trouble. The other rail does not have the inverted angle iron, so will just need two seals at right angles to each other. This one will be very difficult to get at it with any kind of saw I know of, unless I remove a fair amount of something to get at it (though a reciprocating 'sawsall' will probably work best; I may have tor rent a cordless one). I'll keep thinking about it.

 

Edited by PaulEK, 18 December 2015 - 09:06 PM.

[PaulEK]

Finally, here's the weatherstrip I bought today. It has a thick, wide, rubber-ish piece that seems like it will cover a multitude of sins.

 

 

[sidwalkastronomy]

I have  a  ROR  and  where  the  rails  are I  cut  a thin rubber door mat  and  used  that  as  a  flexible  flap  covering  the  rail.  on  the other  side  I used  the rubber  from  the under a garage door  to act as  a flexible  flap

[Galaxyhunter]

I think I get it, but some photos would certainly help. I don't have access to a 3D printer, but am pretty good at scrounging for other materials.

 

I'm going out to the site today to take some photos of my own, and to take some measurements. When we do finally get snow and ice here, I'm going to want to have the rails covered with something. I'm thinking of inverted rain gutters on hinges. We can just flip them over before rolling off the roof.

Are you thinking of something like this?  http://hawkeye-obser...ne/snowgrd.html

4" PVC cut in half mounted by hinges & a handle attached to flip open.

[boutilierspoint]

 

I think I get it, but some photos would certainly help. I don't have access to a 3D printer, but am pretty good at scrounging for other materials.

 

I'm going out to the site today to take some photos of my own, and to take some measurements. When we do finally get snow and ice here, I'm going to want to have the rails covered with something. I'm thinking of inverted rain gutters on hinges. We can just flip them over before rolling off the roof.

Are you thinking of something like this?  http://hawkeye-obser...ne/snowgrd.html

4" PVC cut in half mounted by hinges & a handle attached to flip open.

 

the PVC cut in half gets rid of the problem at the source. Do this and you won't have to do anything else... been there done it!

Edited by boutilierspoint, 27 December 2015 - 06:56 PM.

[PaulEK]

I ended up doing something similar to the PVC cut in half: I used vinyl gutter. I wanted the entire rail covered, so I widened (and also strengthened) the gutter laterally by attaching treated 1 x 2 boards along one side of it. I then attached it along the rail with half a dozen strap hinges. I got it up just before we got our first snow of the winter here. I'm only posting now because I've been out of town for the Holiday.

 

I only have inverted angle-iron on one side, so, since the other side is flat, I just strung some 1 x 6 treated boards on that side. I haven't attached them yet.

 

Before covering the rails, I covered the holes in the walls above the rails with both the rubber stripping imaged above, as well as some more brushes. Before doing that, I cut off the red-highlighted board in one of the photos above with a hand saw I was able to get at it with. That made things much easier. We got more rain after that, so I was able to see if it worked. It helped a lot, but there was still some slight leakage. From what I can tell, I think nearly all of the water getting in now may well be sort of wicking in under the rails, along the 2 x 6 top plates. I can see some light through the wall where they enter, and had not realized that the folks who built the observatory had not put any caulk here. I'll need to wait for spring to caulk the walls really well. What's getting in now is little enough to be acceptable, and should be even less now that the weather has finally gotten below freezing.

 

The rail covers may help, too, but I didn't install them primarily for water shedding, but for preventing snow and ice build-up on the rails. Now I can simply flip them over and roll the roof along smooth metal.

 

I'll try to post photos of what I've done, but it may be a day or two before I can get out there again.

 

Thanks again for all the helpful suggestions!

Edited by PaulEK, 28 December 2015 - 01:37 AM.

[Cotts]

A 'toothpaste-is-already-out-of-the-tube' approach is to admit that some water will get into your obsy via the rails and the required openings no matter what you do and to ensure that the water does not leak down from the rails into your walls (seal the #$#$% out of the top of your walls with silicone or some such waterproofer).  

 

Secondly, ensure that the building is well ventilated via the soffits and some way to admit air in at ground level (there are screened vents available at building supply stores).   The combination of wind and convection will ensure that the humidity in the observatory is always as low as possible.  If water gets in and just stays there because you have done too good a job of sealing the building you'll be more susceptible to rot and fungus, not only in the walls and roof but in your valuable telescopes and mounts that have to live inside....

 

Dave

[Kellogg]

I think I get it, but some photos would certainly help. I don't have access to a 3D printer, but am pretty good at scrounging for other materials.

 

I'm going out to the site today to take some photos of my own, and to take some measurements. When we do finally get snow and ice here, I'm going to want to have the rails covered with something. I'm thinking of inverted rain gutters on hinges. We can just flip them over before rolling off the roof.

 

Apologies for the late reply, i'm not around these parts as often as I should be.

Anyway here are two pics I just took. The first shows small slivers of silicone sealent that I replace each year to funnel the water away. I place these every foot or so. The second pic shows the solution for the underside of the beam, anything that forces the water down would work here, maybe a piece of angle iron?

[PaulEK]

I'm coming back to this old thread because I ended up more or less solving the problems. I used brushes and the rubber weatherstripping I showed up above. As Cotts says in post 20, having a perfect seal would be bad. Still, standing water has only happened once since I finished the weather sealing, and that was when we had 6 inches of rain in less than 24 hours, with strong wind that made the rain fly nearly horizontally. And, very little water got in, none of it anywhere near the equipment, and it dried up quickly.

 

Here's a photo of the side with the angle iron (I did end up sawing off that awkward bit, and just used a hand saw with a narrow blade):

 

[PaulEK]

And here's the side without angle iron, which was much more straightforward:

 

 

 

 

The brushes not only keep out water, but bugs and other critters as well. Some still get in, though. I was stung a week ago by a yellow-jacket while I was getting things ready in the afternoon for an outreach event that night. I had already sprayed** a couple of small nests that I'd found a few days earlier, but this one was a stray. It's nice that they aren't active at night!

 

**I was glad to find a spray that uses peppermint oil, since it is less caustic and harmless to kids and other animals. I can report, though, that it instantly killed the wasps and yellow-jackets.

 

 

 

[TCW]

A 1/4" break in the rails would stop water from running inside as would sloping the exterior portion of the rail away from the building,

[mikeDnight]

To prevent rain penetration between roof and observatory walls I covered the roof with rubber roofing material which is glued to the ply board roof. I allowed the rubber sheet to hang over the roof edge as a skirt and secured by plastic edging. The rubber skirt is slightly longer than the roof/wall divide and drips into a plastic gutter. There is also a strip of the same rubber nailed to the top edge of the observatory walls all round and which also drips into the gutter. When the roof is closed the wall rubber and roof rubber skirts effectively close the gap. No rain enters the observatory! 

 

Mike