Turning sunlight into hot showers: best kits or hacks?

Yeah, the peroxide thing is a bit of a double-edged sword. I tried it once because I was worried about algae, but after a season the tubing got all brittle and started leaking... not worth the hassle for me. I switched over to some black UV-resistant poly tubing (think it was labeled for irrigation use), and it’s held up way better than the clear stuff. Still gets a little faded after a year or two, but I haven’t had it crack or anything yet. Not sure if it’s truly “UV-proof,” but it’s definitely less maintenance.

As for the partly cloudy days, that’s been my biggest frustration too. I’ve experimented with wrapping the tubing in those cheap emergency blankets to reflect more light back onto it, but honestly, the gains were pretty minimal unless the sun was really out. One thing that helped a bit was coiling the tubing tighter and putting it on a dark metal sheet - seems like the extra mass holds heat longer, so you don’t lose temp as fast when clouds roll in. Still, without a greenhouse or some kind of insulated box, I think there’s just a limit to how much you can squeeze out of these setups.

I’ve seen some folks build little mini-greenhouses just for their coils using old windows or even clear storage bins. Looks goofy, but apparently it helps trap enough heat to make a difference. Haven’t gone that far myself yet... I keep hoping for a hack that doesn’t involve building a whole sunroom just for hot water.

If anyone’s managed to crack the code for decent temps on those in-between days without going full DIY greenhouse, I’d love to hear about it. Otherwise, I guess we’re all just at the mercy of the weather gods. At least the cold showers build character, right?

Yeah, I’m with you on the peroxide - tried it once and my lines turned to mush by the end of summer. Black irrigation tubing is definitely the way to go, though I wish someone made a truly UV-proof version that didn’t cost a fortune. I’ve also played around with those “solar shower” bags, but honestly, they’re just not practical for daily use if you want more than a quick rinse.

On the cloudy days, I’ve had slightly better luck using foam board insulation under the coil and then covering it with an old glass door. It’s not a full greenhouse, but it traps enough heat to keep things warm-ish even when the sun dips behind clouds. Still not perfect - if there’s no sun at all, you’re out of luck - but it beats shivering every time a cloud rolls by.

Honestly, unless you’re willing to go all-in on a proper collector box or evacuated tubes (which gets pricey), there’s always going to be some compromise. At least we get bragging rights for doing it ourselves...

I get the whole “there’s always a compromise” thing, but honestly, I think people overestimate how much you need to spend for a decent collector box. I built one out of scrap plywood, some leftover insulation, and a busted window I found on the curb. It’s not pretty, but it gets the water hot enough for a real shower - even on days when the sun’s just peeking through. Sure, it took a weekend and a few curse words, but it beats fiddling with those solar bags or shivering under lukewarm water. Sometimes DIY doesn’t have to mean settling for “good enough.”

“I built one out of scrap plywood, some leftover insulation, and a busted window I found on the curb. It’s not pretty, but it gets the water hot enough for a real shower - even on days when the sun’s just peeking through.”

That’s actually pretty inspiring. I keep seeing all these fancy kits online with price tags that make my wallet sweat, but what you did sounds way more doable. Did you have to worry much about leaks or pressure? I always wonder if those DIY collector boxes can handle any kind of decent flow, or if it’s more of a trickle. Also, how did you connect it up to your shower setup - just gravity-fed, or did you rig up a pump?

I get what you’re saying about “good enough” - sometimes the homemade stuff ends up working better than the store-bought gadgets, at least for certain things. My uncle once made a solar heater out of black-painted copper coils and an old glass door, and it got so hot he had to mix in cold water just to keep from burning himself. Not sure I’d go that far, but it goes to show you don’t always need fancy materials.

One thing I’m curious about: does your setup hold heat well into the evening, or does it cool off pretty quick once the sun dips? I’ve read insulation makes a big difference, but never tried building one myself. Also, any issues with freezing if you leave water in there overnight?

Honestly, I’m tempted to try something similar. The worst part of camping for me is always those sad little solar bags that barely get lukewarm unless it’s July and there’s no wind. Your approach sounds like a solid upgrade - might not win any beauty contests, but who cares if it works?

I get the appeal of DIY, but honestly, I’ve seen a lot of these homemade setups end up leaking or losing heat way faster than folks expect. Even with insulation, plywood and scrap windows don’t hold up long-term - especially if you’re actually running a shower, not just filling a bucket.

“sometimes the homemade stuff ends up working better than the store-bought gadgets”

“sometimes the homemade stuff ends up working better than the store-bought gadgets”

Yeah, I’ve patched up enough leaky “innovations” to know what you mean. Scrap windows and plywood sound great until you’re ankle-deep in water that’s supposed to be in your tank. If you want a hot shower that doesn’t turn into a cold surprise, those prefab kits really do save headaches. I’ve seen folks try to rig up old garden hoses and black barrels - works for a bit, but once you want actual pressure or consistent heat, it’s a different ballgame. Sometimes paying more upfront means less duct tape down the line...

Sometimes paying more upfront means less duct tape down the line...

That’s been my experience too, especially once you’re dealing with anything more complicated than a camp shower. I’ve seen plenty of “innovative” setups using black barrels and hoses, and they’ll get you warm water on a sunny day, but the minute you want steady pressure or to avoid leaks, things get tricky.

Prefab solar kits aren’t perfect, but at least they’re designed to handle the expansion and contraction from heat cycles. I’ve replaced a lot of homemade rigs where the fittings just couldn’t keep up - PVC gets brittle, seals fail, and suddenly you’re back to cold showers. If you’re just looking for a quick rinse after yard work, sure, DIY can work. But for daily use? Those kits are worth a look.

One thing I will say: if you do go the DIY route, spend the extra on quality valves and connectors. That’s usually where things go sideways.

Paying more upfront definitely saved me headaches. I tried the “black barrel and hose” trick a few years back - looked clever, cost next to nothing, but it was a mess after the first summer. Here’s what happened:

- Barrel warped from the heat, so the lid never sealed right again.
- Cheap hose fittings started leaking after a couple weeks of pressure changes.
- Water got hot, but not always when I needed it (cloudy days = cold showers).
- Ended up patching things with tape and random clamps way too often.

Switched to a prefab solar kit last year. Not perfect, but:

- The tank actually holds pressure without bulging.
- Valves are solid - no more surprise leaks at 7am.
- It’s insulated enough that I get warm water even if the sun dips behind clouds for a bit.

If you’re just rinsing off after mowing the lawn, DIY is fine. But if you want something you can count on every day, prefab is worth it. Only thing I’d add: even with a kit, check all the seals before you install. Some of them come with pretty flimsy washers.

One thing I learned - don’t cheap out on pipe thread tape or sealant. That’s where most of my leaks started, both DIY and kit builds. Spend an extra couple bucks there and you’ll save yourself a lot of cursing later.

Not saying DIY can’t work, but unless you really enjoy tinkering (and fixing), prefab saves time and frustration in the long run.

Not saying DIY can’t work, but unless you really enjoy tinkering (and fixing), prefab saves time and frustration in the long run.

Totally get where you’re coming from. I tried to cheap out with a homemade setup too - thought I was being clever, but it turned into a leaky science project by mid-July. The “fixes” just kept piling up. I’m all for saving money, but sometimes it’s just not worth the hassle.

You nailed it about the pipe thread tape and sealant. I learned that lesson the hard way - thought I could get away with the bargain stuff, but ended up with drips everywhere. Spent more time chasing leaks than actually enjoying a hot shower.

Prefab kits aren’t perfect, but at least you’re not constantly patching things up. Still, I do wish they’d use better washers... seems like even the pricier kits cut corners there. Anyway, good call on spending a little more upfront. Sometimes “buy once, cry once” really is the way to go.

Funny how those “quick fixes” always seem to multiply. I’ve patched more leaks than I care to admit, and you’re right - cheap tape is basically a false economy. Still, I’ll say this: if you’re the type who likes to tinker and troubleshoot, DIY can be rewarding... just not always relaxing. Prefab kits are far from flawless (those washers, ugh), but at least you’re not spending every weekend with a wrench in hand. Sometimes peace of mind is worth the extra bucks.

Honestly, I get the appeal of prefab kits for the peace of mind, but I’ve seen a few that were more hassle than they were worth. Last month, I helped a neighbor with a “plug and play” solar shower kit - ended up chasing leaks around the connections for hours. Sometimes, a careful DIY setup with decent materials (not the bargain bin stuff) actually holds up better. It’s a bit more work upfront, but you know exactly what’s going into your system. Guess it comes down to whether you want to trust the kit or your own handiwork...

I hear you on the prefab kits - sometimes they’re just a box of headaches with a shiny label. Had a buddy who swore by his “easy install” solar water heater, but half the fittings were plastic junk and started cracking after a month in the sun. I always say, if you’ve got the patience, sourcing your own parts and assembling it yourself usually means fewer surprises down the line. Might take longer, but at least you’re not stuck with whatever shortcuts the manufacturer took.

- Totally agree about the prefab kits being hit or miss.
- I went down the “all-in-one” route once, thinking it’d save time - ended up replacing half the parts anyway.
- If you’re handy with tools, piecing together your own setup just gives you more control over quality and fit.
- One thing to watch: sometimes sourcing parts can get weirdly expensive, especially with copper these days…
- Also, double check sunlight angles for your roof before buying anything. Learned that one the hard way - my first panel barely got any sun in winter.

Copper prices are wild lately, right? I tried to build my own collector last summer and nearly choked at the hardware store checkout. Ended up mixing in some PEX where I could get away with it, but not sure how that'll hold up over time with the temps. Has anyone here had luck with alternative materials for the piping?

On sunlight angles - totally hear you there. My neighbor thought he'd nailed his orientation but forgot about a big pine tree that blocks half his roof come winter... Not fun. I read somewhere you can use a simple cardboard cutout and a phone compass app to test angles before committing to anything permanent. Maybe a bit basic, but it saved me from a similar mistake.

Anyone think it's worth hunting for used panels or parts? Sometimes I see old solar pool heaters online for cheap, just not sure if they're worth the hassle or if they lose efficiency too fast.

Ended up mixing in some PEX where I could get away with it, but not sure how that'll hold up over time with the temps.

I totally get the sticker shock on copper - my wallet still hasn’t forgiven me for last year’s “quick trip” to the hardware store. I went with PEX too, but only for the return lines where it stays cooler. For the collector itself, I chickened out and used black-painted steel pipe. It’s heavier and rusts eventually, but it was way cheaper and seems fine so far (just keep an eye out for leaks).

On used panels: I actually picked up a couple old pool heater mats off Craigslist. They looked rough but after a good cleaning, they worked surprisingly well for pre-heating water. Not as efficient as shiny new stuff, but for the price? Hard to complain. Just check for cracks or brittle spots - they don’t all survive being rolled up in someone’s garage for years...

I went with PEX too, but only for the return lines where it stays cooler.

- That’s smart. I’ve heard PEX can get sketchy if it sees collector temps for long - some guys at work mentioned it gets soft or even starts to sag.
- Black-painted steel is a cool budget move, though. How’s it holding up with the rust? I’m always paranoid about leaks showing up months later.
- Those pool heater mats are a neat idea. Did you have to rig up any special fittings to connect them, or did standard hose stuff work?

Curious if anyone’s tried running glycol in their DIY setups for freeze protection? Seems like a hassle but maybe worth it in cold spots...

I’ve seen PEX get weirdly soft near the collector, too - almost gummy if it’s a really hot day. I’d be nervous running it for supply lines unless there’s a heat dump somewhere. As for black steel, I’ve patched up more than a few leaks after one season, usually at the joints where rust sneaks in. Seems like you either baby those lines with paint or just accept you’ll be redoing them eventually.

On glycol: honestly, it’s a pain to flush and refill, but I’ve seen setups survive brutal winters because of it. Just gotta watch out for leaks - glycol stinks when it gets old and sticky. Ever try using flexible copper instead? Pricey, but less drama long-term.

I’ve seen PEX get weirdly soft near the collector, too - almost gummy if it’s a really hot day.

Yeah, PEX and high heat don’t mix. I’ve had to replace sections where it basically turned into licorice. If you’re set on plastic, at least use PEX-AL-PEX for the collector loop - it holds up better, but still not perfect. Black steel is a pain for leaks, you’re right, and painting every joint is tedious. Flexible copper’s expensive, but it’s the only thing I’ve seen last more than a decade without drama. For glycol, I always recommend adding a pressure gauge and a sight glass to the loop - makes spotting leaks and topping off way less of a headache.

Flexible copper is like the unicorn of plumbing - everyone talks about it, but my wallet screams every time I look at the prices. Is there a trick to finding it cheaper, or do you just have to bite the bullet? I tried PEX once (not the AL kind) and it literally sagged so much near the collector, I thought it was going to drip off the roof. I’m tempted by black steel just because it’s sturdy, but painting all those joints sounds like a chore I’d keep putting off… and then regret later. Has anyone tried mixing materials for different sections, or is that just asking for trouble?

I tried PEX once (not the AL kind) and it literally sagged so much near the collector, I thought it was going to drip off the roof. I’m tempted by black steel just because it’s sturdy, but pain...

Mixing materials is a bit of a gamble, honestly. I’ve done copper to PEX transitions in a couple rentals - bite the bullet on copper for the collector and first few feet, then switch to PEX where it’s out of sight and not getting roasted by the sun. Haven’t had leaks, but I keep wondering about long-term durability. Black steel’s solid, but like you said, painting is tedious, and rust creeps in if you slack. Curious - has anyone tried that flexible stainless stuff? Wondering if it’s worth the price or just another “unicorn.”