I’ll be completely honest here: I know as much about plumbing as I do marine biology or rocket science (which is to say, next to nothing).
So when I told a friend “you know, I always think tap water is way colder in water,” I had no idea how to respond when she asked how I thought that’d happen.
An even more embarrassing admission; I’m not even sure where the reservoir that holds the water that runs through my sink is, or if it’d even be possible for the liquid in it to be affected by the weather.
So, I thought I’d ask Myles Robinson ― former boiler repair company owner and current CEO of UK Composite Doors ― whether I was losing it in the run-up to Christmas, or if this was a real thing.
So... Is tap water really colder in winter?
Yes, Myles says.
He told HuffPost UK: “tap water is definitely colder in the winter. It all comes down to a combination of factors, the water source, the pipes, and how they interact with the colder weather.”
“Most water systems draw from reservoirs, rivers, or groundwater. In winter, these sources naturally drop in temperature, especially in areas with freezing conditions,” he continued.
“Even groundwater, which is insulated by the earth, gets colder as the ground above freezes. So, the water entering your home starts off colder during winter months.”
If you’re thinking “wait, wouldn’t it warm up in the pipes?”, we were in the same boat ― but Myles has answers.
“Pipes running through unheated spaces, like basements, crawl spaces, or underground, are understandably more exposed to the colder air or ground temperatures in winter,” he explained.
“As the water sits in these pipes, it cools even more before reaching your tap. The longer the run of pipe from the main supply to your tap, the more pronounced this cooling effect can be.”
Does tap water get hotter in summer too?
I knew I wasn’t imagining lukewarm glasses of water in the colder months!
“Interestingly, in the summer, the opposite can happen. Heat from the air or soil can warm up the water in your pipes, making it feel less refreshing than winter’s icy flow,” Myles said. Huh!
By the way, if freezing tap water is bothering you, the home expert says there are steps you can take to get rid of the problem.
“If you’re noticing your tap water feels shockingly cold in winter, especially in older homes, you might want to check if your pipes are insulated,” he told HuffPost UK.
“Proper insulation won’t stop the water from being cooler—it starts that way from the source, but it can keep your pipes from freezing, which is a much bigger concern!’’