Frost-free hose bib on rainwater tank?

We live in a mildish winter area. We can get down to 0 degrees F, but our diurnal swings are usually 30-50 degrees in a day. We rarely get more than a couple days in a row with highs below freezing.

We have a 55-gallon rain barrel by the chicken coop that doesn't freeze. Pipe fittings do freeze. We use the water for the chickens through the winter, but have to dip it out from the top.

We want to add rainwater collection to every outbuilding, but don't want to add heat tape, and would like spigot access on at least some.

Can you install a silcock (frost-free hose bib) on a rain barrel? I assume if the water doesn't freeze around the backside of silcock that would work? (And assuming the rain barrel has a removable top so we can access the backside for installing)

Is there any silcock-equivalent bulkhead fitting for cisterns with 2" fittings? I mean an outlet that shuts off well behind the wall, so that the exterior fitting never holds water in it. If not, I guess we could step it down to the size we need, but have to be careful that none of those fittings hold exterior water.

I see no reason you couldn't install a sillcock on a rain barrel. I think you would need to invent a bulkhead seal, possibly by screwing/bolting the sillcock exterior wall plate to the barrel wall and siliconing behind it. Maybe you could cut a rubber gasket or two to do the job.

I'm on my celphone right now, so I'll try to post some pics when I'm back at my PC. In your situation, since you'd like 2", I think I'd use a PVC ball valve installed well inside the tank. I'd have a welder or machine shop make me a custom street key so I could open and close the valve. (I'd install the street key through the tank's lid, working the valve with the handle sticking out above.) Then I'd run PVC through a uniseal to seal between it and the tank. I'd try to run the pipe very slightly downhill, so when you shut the valve the pipe drains out. A 45° elbow JUST outside the tank might help start a little siphon to empty the pipe.

Kimi Iszikala wrote:Can you install a silcock (frost-free hose bib) on a rain barrel? I assume if the water doesn't freeze around the backside of silcock that would work? (And assuming the rain barrel has a removable top so we can access the backside for installing)

We had one of these when we lived in Ottawa. Some municipal workers hooked up our hose to it one day when we were out. The hose effectively defeated the mechanism and burst the pipe inside the house. We were away at the time...   So just don't leave anything attached to the outside spigot part! If you want to be able to have  a hose attached to it, use a quick connect so it's easy to remove as soon as you finish with it. The hose will be fairly low pressure anyway, but depending on the situation and uses for the water, even a low pressure hose has benefits of both relocating the water and decreasing the tendency for it to splash or drip in places you don't want it to do so.

Jay Angler wrote: We had one of these when we lived in Ottawa. Some municipal workers hooked up our hose to it one day when we were out. The hose effectively defeated the mechanism and burst the pipe inside the house. .

Ay yi yi, Jay, what a nightmare! I'm so sorry that happened to you. Good cautionary tale.

Jay Angler wrote: We had one of these when we lived in Ottawa. Some municipal workers hooked up our hose to it one day when we were out. The hose effectively defeated the mechanism and burst the pipe inside the house. We were away at the time...   So just don't leave anything attached to the outside spigot part!

100% correct. Every fall, my nightly checklist / walkabout includes making sure the hoses are depressured and disconnected from the silcock hose bibs outside of the house.

I like T Melville's solution of a tap inside the barrel so that the thermal mass of the water makes it less likely to freeze. In mild UK having a tap (=cock?**) on a water butt (=rainbarrel) is quite normal. To be extra safe you could have a cap that fits over or into the exposed bit of pipe, so that cold air does not penetrate into the pipe and still freeze it from the inside.

**I had to look up sillcock/hose bib as I had never heard of it - It would just be an 'outside tap' in the UK.

Nancy Reading wrote:I like T Melville's solution of a tap inside the barrel so that the thermal mass of the water makes it less likely to freeze. In mild UK having a tap (=cock?**) on a water butt (=rainbarrel) is quite normal. To be extra safe you could have a cap that fits over or into the exposed bit of pipe, so that cold air does not penetrate into the pipe and still freeze it from the inside.

**I had to look up sillcock/hose bib as I had never heard of it - It would just be an 'outside tap' in the UK.

The frost-free hose bib is a modified version of what I think you mean. (See attached picture.) They're usually installed through a wall, with the washer and seat that open and close to let the water flow being located somewhere that stays above freezing. The plastic spacer it comes with is thicker on the top than the bottom, so if it's installed right the water from the washer onward drains out when you shut it off. As far as I know, they aren't made in 2" diameter, because they're made to connect garden hose, which only comes in one size. I basically copied the idea, but with 2" parts.

T Melville wrote:In your situation, since you'd like 2", I think I'd use a PVC ball valve installed well inside the tank.

Thank you for this detailed design! I think it might be more complicated than we need, but it is great to have a 2" solution in our bag of tricks.

I'm thinking that you'd have to make sure you didn't let the water level in the rainwater tank get too low without the hose bib parts getting emptied first.  If you're in a cold enough location, or simply an atypically long cold snap, water in the tank may freeze. There are things you can do to help that - multiple layers that includes heat tape inside of insulating layers, but insulation without a heat source won't help and water is a thermal hog.

The catch is: where I live the "Daily Minimum Temperature" for our two coldest months are 1.1 C and 1.5 C. But these numbers are averages over decades. We've lived in the area for approximately 30 years and we've had "snow on the ground" for a full week at least 3 times. Other winters, it's hardly ever gone below +5 C. Averages are just that - it's important to look at the "extremes" and consider that those extremes have been tending to get wilder. However, I find that getting the "extreme" temperatures is harder - much harder than "averages" because extremes are treated like a one-of event. I finally found one chart that's a bit vague, but we fell into having a 10 to 13% chance of having temperatures from 0C to -9C somewhere between mid Dec to mid Jan. We had a further 8 to 10% chance of having similar cold temperatures from mid Jan to mid Feb and slightly less odds of it happening early December. However, I distinctly remember my mom visiting in Nov and wishing she'd brought snow boots... back around the mid 1990's. We have all of 1 farm water spigot of the "hydrant" style - similar to the image above except operated by a lever and the unit is vertical and shuts off and drains underground. I'd love to have 3 or 4 more for peace of mind. Ours don't need to be all that deep. I've seem pictures of them that are more than 3 ft deep for places with seriously deep frost lines! After one particularly difficult winter, I know several local farmers wanting to put these hydrants in. And yet when we had to pull ours out for repairs and Hubby took it to a shop to get parts, they pretty much laughed at him and said we'd never need it... wrong!!! We got it fixed and reinstalled and needed it desperately within a year.

This is an interesting topic, the last concept is clever, but they seem to be rarely used. Is that the case?

Here are some other ideas;
https://www.amazon.com/Freeze-Proof-Faucet/s?k=Freeze+Proof+Faucet

T Melville wrote:I'm on my celphone right now, so I'll try to post some pics when I'm back at my PC. In your situation, since you'd like 2", I think I'd use a PVC ball valve installed well inside the tank. I'd have a welder or machine shop make me a custom street key so I could open and close the valve. (I'd install the street key through the tank's lid, working the valve with the handle sticking out above.) Then I'd run PVC through a uniseal to seal between it and the tank. I'd try to run the pipe very slightly downhill, so when you shut the valve the pipe drains out. A 45° elbow JUST outside the tank might help start a little siphon to empty the pipe.

I just want to say how fantastic this idea is, on so many levels. First the valve inside the tank, rather than on the surface, insulating it with the water inside. Second, no metal fittings, so less conduction of cold through the parts... even those frost-proof sillcocks fail if not installed properly or used properly (hose removed each time). Third, if you wanted to insulate the tank, no special measures need to be taken at the outlet, no access necessary to operate the valve there, just a usually dry pipe.

You might even be able to fashion a street-key out of PVC pipe fittings (some pipes, a tee for the handle, and a bushing to strengthen the end where it operates the valve)
This could do two things: A.) eliminate the welding of a metal key and B.) since it is less conductive, that would allow this non-metal key to just live in the tank, or be forgotten now and then?

John C Daley wrote:This is an interesting topic, the last concept is clever, but they seem to be rarely used. Is that the case?

If you're referring to the farm "hydrant", yes they're not super common, but farms with animals to water are often willing to pay the price as the convenience and piece of mind is totally worth it. They last decades (ours is over 30 years old) so if you amortize the cost and value in the labor saved from having to drain systems and the stress of worrying about pipes freezing, I think they're totally worth it. The last time we had a really cold, snowy winter that seemed to go on for months, there were a lot of locals who were agreeing with me!

This seems like a great deal of fuss.

Why not use a jiggler siphon attached to a 3/4" garden hose? Move the water you need, gravity powered, then bring it inside for the night.

It's not a 2" solution, but that seems like massive overkill for a 55 gal barrel.

Douglas Alpenstock wrote:Why not use a jiggler siphon attached to a 3/4" garden hose? Move the water you need, gravity powered, then bring it inside for the night.

Well, maybe I just got a dud, but I found that our jiggler was only effective if the barrel was over half full. Two issues: one was water pressure, the second was that if your filtration isn't great, trying to get the jiggler started tended to stir up the gunk in the water and the less water, the more gunk/volume.

Our first one  was from a company that's usually reliable. Hubby got a cheaper one later and it was worse.

Jay Angler wrote:... if your filtration isn't great, trying to get the jiggler started tended to stir up the gunk in the water and the less water, the more gunk/volume.

Very true. Mine doesn't like a lot of gunk either.