Just bought a condo and am panicking about the bath situation

October 23, 2023 6:02 PM

The main reason I bought the apartment is that it has a large, luxurious looking bathtub. I would ideally like to take 2-3 baths per day. I just found out that: (1.) The flow rate is extremely slow, it would take maybe 1 hour to fill the tub, and (2.) At the hottest temperature, the water is not all that hot, so by the time the bathtub fills, it will be slightly warmer than lukewarm. Looking for solutions and wondering if a tankless water heater would even work, assuming it gets approved.

My previous tenant told me that everyone in the building gets the same sized pipe, so it's unlikely that I could increase the water flow. I am thinking of maybe trying to get a tankless water heater, if the building approves it, but I'm wondering if the slow water flow would doom that approach.

I'm willing to spend basically any amount of money up to $30K to solve this problem, but obviously it's contingent on what my building will allow. If I cannot take hot baths, I will have no choice but to sell the unit. I'm quite upset about this, I had been looking forward to taking baths again for the past year.

posted by jtothes to Home & Garden (19 answers total)

Ensure there are no filters/screens/other devices in your bathtub spout that would restrict flow.

Does each unit have its own hot water heater already, or is there a common hot water boiler for multiple units or the entire building?

If your unit has its own dedicated hot water heater then see if you have the ability to increase the temperature that it heats the water to.

If the unit does not have its own hot water heater then you may want to look into your local code to determine if there is a minimum temperature for hot water delivered at the spout.

If you're willing to spend up to $30k to take hot baths multiple times a day then maybe look at replacing the tub with a "heated soaking tub" instead of adding in a tankless water heater (I'm not endorsing this particular site/manufacturer, it's just a starting point to learn about them):

https://www.tubz.com/soaking-baths-heated-soaker.htm

There are whirlpool/jacuzzi options with those tubs as well.

(Note you would want a heated SOAKING tub, **NOT** a heated SURFACE tub)
posted by de void at 6:19 PM on October 23, 2023 [11 favorites]

When I had a bathtub installed, I asked my terrific builder to insulate it. He used the foam carpet underlayment that would otherwise have gone to the dump. It helps keep the water warm because once I'm in the tub, I like to stay for a while. You might be able to have someone add spray foam insulation, or other insulation.

When I want a bath, which is occasional, I turn up the hot water at the hot water heater. Find your hot water heater, it may be set low.

I have the flow from the hot water heater set just high enough for reasonable showers, because my son lived with me and took long hot showers at full blast. It has worked out just fine for me. Ask a plumber to review the flow. You might be able to get water from the tap and use an adapter similar to this to fill from 2 sources.

You may be able to get an on-demand hot water heater installed in the bathroom. Heating water uses lots of electricity, so make sure an electrician gets involved at some point. My tub is a soaking tub, generously sized, and I usually bring my water kettle to the bathroom for several extra liters of boiling water.

To save a little on heat in winter, you can let the water stay in the tub until it's cool, so the heat warms the apartment. You could also look into the heaters used for hot tubs, as well as the chemicals to keep the water clean, and an insulated cover.
posted by theora55 at 6:30 PM on October 23, 2023 [2 favorites]

Response by poster: To clarify, the unit does not have its own hot water heater, all water comes from a central source. It is a relatively new building, so I believe the faucet is functioning as it was designed. I do not believe there are any filters/screens/other devices in the spout restricting flow, I believe the pipe to the tub is just small.
posted by jtothes at 6:33 PM on October 23, 2023

To echo what others are saying: I would get a plumber in there to make sure the flow isn't blocked or filtered or anything. I had a friend who lived in an apartment with a terribly flowing shower for years til I suggested he ask the landlord about it, and it was fixed in a day. And yes, you might be able to increase the temperature on the hot water if the heater is in your apartment. A manual should tell you how, or check with a plumber.
posted by bluedaisy at 6:34 PM on October 23, 2023

Response by poster: *its own hot water heater.
posted by jtothes at 6:34 PM on October 23, 2023

Before hiring a plumber, check the flow rate from the bathroom sink. If the sink provides better flow, it should be possible to improve the flow rate from the tub. If the sink is also very slow, then the problem is further upstream: either the pipes are small, or there is a blockage somewhere.
posted by Winnie the Proust at 6:39 PM on October 23, 2023 [4 favorites]

Check the water temp at various times of day. Shared hot water is often in highest demand from 7 am to 9 am.
posted by theora55 at 6:39 PM on October 23, 2023 [1 favorite]

Certainly not a 30k solution, or even an elegant one, but this immersion water hearted is useful to further heat up baths: link
posted by raccoon409 at 6:39 PM on October 23, 2023 [5 favorites]

Your faucet may have a temperature adjustment - similar to this:
posted by coberh at 6:42 PM on October 23, 2023 [2 favorites]

Certainly not a 30k solution, or even an elegant one, but this immersion water hearted is useful to further heat up baths: link

Came here to say exactly this. Fill up the tub, drop an immersion heater in, when tub is hot, take out, unplug, get in tub, enjoy.
posted by chasles at 7:25 PM on October 23, 2023 [2 favorites]

“Ofuro” is another term for a heated soaking tub, if you choose to go the major remodeling route.
posted by shock muppet at 7:28 PM on October 23, 2023

Wow. It seems weird to me - a fellow bath-loving homeowner- to leap to the idea of spending tens of thousands of dollars on a remodel without first calling a plumber. If you're willing to spend $30k, then without a doubt the first thing you should do is find a good plumber to actually diagnose what's going on.

Two common issues a plumber can check easily:
1) have the pipes anywhere along the line corroded? If so, grit can be restricting the flow.
2) What about the faucet's cartridge? The cartridge is the guts of the faucet/handle. If grit has corroded that, then it can reduce the flow significantly.

A plumber can easily check both the water pressure and flow by seeing how water comes out of the valve located under the faucet, before it even reaches the faucet.

Also, the size of the pipes to your unit and to each fixture are likely covered by some sort of building code in your country or province. If those pipes are "out of code" that's an issue, but an issue that probably would have been noticed before now given that it's a multi unit building.
posted by cocoagirl at 7:38 PM on October 23, 2023 [9 favorites]

Agreeing with all that you need to get someone in who can diagnose the situation. Even the smallest pipe that could be installed with very low water pressure should still deliver much more than the approximately 2 litres per minute that you are getting. Something is wrong somewhere and you need someone with experience to find out what that is.
posted by ssg at 7:57 PM on October 23, 2023 [6 favorites]

This sounds like it's likely a communal water heater problem, and as a fellow bather, it pains me. But based on a a similar situation in my last apartment that had me in tears after moving in, it could also be an anti-scald valve in the faucet. Give it a google; it's really easy to fix if that's the case.
posted by mostlymartha at 8:17 PM on October 23, 2023 [5 favorites]

Ask other folks in the building if they have these issues, to see if it's really a general building problem, or if it's something specific to your unit.

Also, measure the temperature of the hot water! In the US, there are usually local regulations about the minimum temperature for the hot water. (It's a safety thing for Legionella!) If your profile is accurate, you're in a different jurisdiction, but if there are local rules, you can use them to get the building to crank the boiler up a bit.

Another option is to look into immersion water heaters.
posted by Blue Jello Elf at 8:34 PM on October 23, 2023 [4 favorites]

What is your mains cold water pressure like? A tankless water heater will give you properly hot water at essentially the same pressure as the cold water coming in to it. If that has a poor flow then it won't make any difference (but also, might speak to a different solution).
posted by plonkee at 1:26 AM on October 24, 2023

There may be local regulations on the maximum temperature your hot water can be, to prevent accidental scalding. If your building has an anti-scald temperature then your hot water is always going to be just barely hot. And that sucks. Which means you'll need to heat the water in the tub no matter what.
posted by seanmpuckett at 5:19 AM on October 24, 2023

It's very common that normal sized hot water heaters can't fill a big bath tub. That's why old bathtubs were small. If you had your own hot water heater, they make a special tank called a re-circulation tank (I think?) to fill a large bathtub if you have the space, or tankless was basically invented for this use. But if you don't have access to to the hot water, I'm not sure what you can do other than call a plumber.
posted by The_Vegetables at 7:18 AM on October 24, 2023

Please, don't panic. Spend time before you spend 30K: hire professionals to evaluate the plumbing. Here's a checklist for troubleshooting low water pressure issues in apartments; a small leak in the building's basement could be the cause of this problem in all the units.
posted by Iris Gambol at 4:02 PM on October 24, 2023 [1 favorite]