For most American homeowners, it’s “the more the merrier.” At least when it comes to the number of bathrooms.

Indeed, it’s a good bet that your next home will have at least two bathrooms, and perhaps more. Of all the new houses built in 2016, only a scant 3 percent had 1-1/2 baths or fewer, according to the latest figures from the Census Bureau. Even the number of new places with 2-1/2 baths or fewer fell in 2016.

At the same time, the number of new houses with three or more baths has been on the upswing for more than a generation, nearly doubling from 1988 to 2016. Americans love their loos.

People buying existing houses -- or who prefer to remodel rather than move -- also focus on their bathrooms, according to Harvard’s Joint Center for Housing Studies. The group reports 3.3 million bathrooms were remodeled in 2015, and 151,000 new bathrooms were added.

The boom in bathroom remodeling translates to a lot of money. In 2016, according to the National Kitchen and Bath Association, homeowners spent $38.5 billion on bathroom remodels of all shapes and sizes. That’s an 8.5 percent increase from the previous year. And when the books are closed on 2018, NKBA is projecting that owners will have dropped $46.3 billion on bathrooms this year.

That won’t be money down the drain, either, because bathrooms sell houses -- especially updated bathrooms.

Remodeling a bathroom isn’t a sign of vanity. In fact, vanities were only third on the list of key bathroom features on which improvers spent money. In 2016, they spent more on showers ($7.1 billion) and on flooring ($6 billion) than on under-sink cabinetry ($5.4 billion). On the flip side, they spent just $1 billion on ventilation. In between? Bathtubs, counters, toilets, sinks, lighting, faucets and medicine cabinets.

Homeowners aren’t thinking small when it comes to their bathrooms. Just about all the $38.5 billion spent on johns in 2016 were major remodels, says the NKBA. Just $4 billion was spent on minor jobs.

Things are similarly hot in the kitchen market, as spending on kitchen products went up by more than 10 percent in 2016. And the total for the combined kitchen and bathroom categories came to $147 billion, split evenly between the two.

Nearly three of every 10 dollars spent in the kitchen went to new rooms, while the rest went to remodeling. Cabinets alone accounted for nearly a quarter of all kitchen remodel expenditures, with a similar amount going toward appliance upgrades, according to the trade group.

NBKA notes that spending on kitchens and bathrooms made up a quarter of all residential construction costs in 2016, driven largely by a reignited real estate sector.

“The increase in residential construction in 2016, when housing starts rose by 5.6 percent to about 1.2 million units, resulted in greater demand for products used in the construction of those units,” according to the trade association.

Total construction spending for 2016 came to $600 million, about equally split between new home construction and remodeling.

Meanwhile, the Census figures on numbers of bathrooms point to a little-known fact that could be of interest to potential homeowners: In addition to counting people, the Census Bureau also counts houses -- or estimates their numbers, at any rate. And if you’re house shopping, there are a few stats in there that could have a bearing on your search.

Interested in knowing how much per month you’ll have to pay for your mortgage? According to the Bureau’s 2016 American Community Survey, the biggest payment category, into which nearly 10 million mortgages fall, is $1,500 to $1,999 per month. The next most popular bucket, with 6.5 million, is $1,250 to $1,499 per month.

The rarest mortgages have payments of $200 a month or less. Just 15,000 of the more than 47 million U.S. mortgages can claim that payment.

How much of your income can you expect to go toward your home loan? This may surprise you: The biggest category is a very reasonable 15-20 percent. Next biggest is 10-15 percent. So, if you are worried you will have to pay half your income or more on a mortgage, don’t. Little more than 10 percent of us do.

-- Freelance writer Mark Fogarty contributed to this report.

The next time you get behind a slow-moving tractor-trailer hauling what looks like a house, or parts of one, don’t scoff. The end result may be a better-built, less-expensive place than the one you live in.

Sure, most people prefer to live in a so-called stick-built home: one that’s put together on the job site, board by board, nail by nail. But it may surprise you to learn that many houses are built, at least to some degree, offsite in a controlled environment -- out of the weather and with far less waste.

The broad heading for this aspect of home building, which Tom Hardiman at the Modular Home Builders Association calls “three-dimensional volumetric construction,” is prefabrication (“prefab” for short).

There are many types of prefab. One is panelization, a term that covers several different techniques. Devin Perry, director of the Building Systems Council at the National Association of Home Builders, says it’s “a catch-all” label that includes pre-engineered floor and ceiling trusses and entire walls. The walls can come framed out, ready to be lifted into place, or they can be almost complete with siding, drywall, wiring, plumbing, windows and insulation.

Many major builders who put up the same three or four models over and over again use some form of panelization. But most smaller builders, the guys who put up only a few houses a year, still prefer to build the old-fashioned way, maintaining that it’s cheaper to do so.

However, Hardiman says the high demand for houses, rising costs and the lack of labor to build them are causing more and more builders to rethink that assessment. “They realize they can’t keep building like they used to,” he says. “They have to be more efficient.”

And building in a climate-controlled factory is nothing if not efficient. Here’s a shorthand version of the process:

The materials are sent to a factory, where they are stored under cover, preventing warping from snow, rain and the hot sun. As the lumber is needed, it’s placed on a series of rollers where it is cut -- sometimes by a skilled worker, other times by a programmed robot -- to the correct size. Still indoors, the pieces are put together, placed on a flatbed truck and hauled to the job site.

It happens quicker than the lumber could be cut and assembled on property -- and remember, time is money. There’s very little waste, if any, and no lost work days because of harsh weather conditions.

There are many other types of prefab construction, including modular homes, manufactured homes, log and timber homes, and structured insulation panels. Modular and manufactured are two of the more common.

Modular construction is a method in which the house is built in large three-dimensional boxes or modules in the factory and shipped to the job site, where they are lifted into place by a crane. Once assembled and permanently attached to a foundation, they are virtually indistinguishable from conventionally built houses. And they are built to local building codes, so they meet the same requirements as site-built houses.

Surprisingly, considering their positives, modular houses have made very few inroads in the housing sector. They reached their peak in 1998, when they accounted for 4 percent of total housing starts, says Perry of the NAHB. But since 2009, they have taken only a 2 percent share. “There has been a slight decline over the last 20 years,” Perry says, “but interest in them has been increasing lately.”

Once known as mobile homes or trailers, manufactured houses were rebranded some time ago to escape their poor image. Nevertheless, they lost their luster around the turn of the century and are just now starting to make a comeback.

In 2000, manufacturers were in their heyday, producing 350,000 to 370,000 units a year. But by 2014, production had slipped to just 64,000 units. However, the NAHB counted 94,000 manufactured homes last year, and expects production to hit 100,000 this year and 111,000 in 2019.

Unlike other factory-built homes, manufactured homes are built to a federal building code promulgated by the Department of Housing and Urban Development. The HUD codes preempt local codes, which are often more stringent.

The units are completely constructed in a factory on a chassis and axles much like the frame your car rides on. They are then delivered via trailer -- hence the “trailer park” term -- to the site. Sometimes units are placed on a permanent foundation; sometimes they are simply parked on the lot.

While it is true that many manufactured homes never move again, some do. As long as the home is still solid enough to withstand the rigors of the journey, the wheels can be put back on and the home towed to another site. The chassis will always be there as part of the structure.

So you’ve sold your house and are about to move into a new one. Other than the physical move itself, you think you’re about done with the process.

Well, think again. You still have plenty to do.

For starters, notify your utility providers that you will be leaving your current address on the day you close the deal on your old place. Once you close, the utilities are your buyer’s responsibility.

At closing, you might give the buyers a list of the house’s utility providers and their phone numbers. This isn’t required, but it is a courtesy, especially if they’ve been cooperative through the entire process.

It’s also a nice gesture to dig up all the manuals (if you still have them) for your appliances and hand them over to your buyers. That way, they’ll be able to safely operate that fancy range or refrigerator, and have the customer service phone numbers at hand, if needed.

While you’re dealing with the gas, water and electric companies, set up those services for your new home. If the new place is in the same service area, this should be a simple matter of switching your existing account to a new address. But if you are moving farther, you might have to post a fee to open a new account. Don’t forget your other services such as cable, trash pick-up and the like.

Let the post office know your new address, and send change-of-address notices to your friends, relatives and credit accounts. If you don’t notify your creditors, you could be hit with expensive late fees and penalties as your bills are slowly rerouted.

Call your insurance agents to tell them of your impending move. You’ll need to have home insurance in place at the closing on your new digs, and proof of coverage. If you are moving into a flood zone, you might also need flood insurance; otherwise, your lender will balk at closing. Fortunately, flood coverage is available from more than just Uncle Sam’s National Flood Insurance Program. Many private carriers also offer policies, so shop around. Just be sure to have it in place at closing.

Of course, you’ve already lined up a professional mover or a gaggle of buddies to help haul your stuff. But have you started bringing home plenty of boxes? What about newspapers or bubble wrap so you can protect your most valuable and delicate items?

If you are using a moving company, have some cash on hand for tips -- if they do a good job. As for friends, you’ll want to provide lunch and maybe even dinner. Pizza, perhaps, or sandwiches, and obviously some cold drinks -- or hot, depending on the time of year you are switching houses.

While awaiting your move, it might be a good idea to learn your new neighborhood. Figure out your new commute to work; find out where the grocery store and other essential shops are located; ascertain where the restaurants, movie theaters and other entertainment venues are.

Here, your local realty agent -- or the builder’s salesperson, if you are buying a new house -- can be of immense help. He or she should be able to provide maps, pamphlets and other information that can be extremely useful.

At settlement, you’ll be given a stack of important documents, so don’t lose or misplace them in the chaos of moving. Make some kind of provision to put your papers in a safe and secure place until you can store them permanently.

You’ll need your closing statement and perhaps some other documents come tax time. And keep receipts for any move-related expenditures. If you are moving because of work, you may be able to write off these expenses, as long as you meet the IRS’s rules and requirements.

Unless your children are old enough to help with the move, make plans to keep them out of the way. Hire a sitter, or leave them with a friend or relative. But don’t shut them out of the move completely. After all, this is their new home, too. Once everything is unloaded into the proper rooms, the kids can be brought back to help unpack a few things.

Speaking of progeny, make sure to enroll them in their new schools prior to the move. Take them to see the school so they can familiarize themselves with the building, and possibly meet a teacher or two and a few new classmates. Any advance work of this kind will help make the transition smoother.

Along this same line, you might want to walk around the new neighborhood on a weekend with your kids in tow, so all of you can meet the new neighbors. If no one is outside, don’t be shy about knocking on doors and introducing yourselves.