A second kitchen may sound extravagant, but for luxury homeowners serious about entertaining, it’s becoming an in-demand amenity.

Unlike a butler’s pantry, which is little more than a sink and extra cupboards, a second kitchen is fully functional with all the appliances. It’s where homeowners do most of the food prep and dishwashing while reserving the primary kitchen for dining and entertainment.

The trend came to the fore on HGTV’s Rock the Block, which features the network’s stable of home improvement stars competing to design the best house in the neighborhood. Several projects have included accessory kitchens.

“Rock the Block really elevated it to the forefront of peoples minds,” Rachel Stults, managing editor at Realtor.com, tells Insider. “I think if you have the money, if you have a luxury home, it makes sense.”

Of course, a double kitchen could double a home’s need for hot water. Consult your propane supplier to determine the right size tankless water heater to meet the demand.

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