Technically speaking, a California Room is not a room at all. Builders tend to define a room as a structure with four walls. Instead, part of it is a porch and part of it is a room.

Although California Rooms are technically classified as outdoor spaces and therefore do not count toward the square footage of the house, they do have protection from the outside world.

For example, California rooms have a roof to protect them from rain and sunlight.

However, unlike a sunroom or solarium that has windows on all sides, a California room opens up to the outdoors on one or more sides.

These rooms do not have to be attached to the house. California rooms can be built independently in the backyard, adding electric lights for evening use and often a fireplace to add ambiance.

If there is not enough backyard to support a freestanding structure, some homeowners will convert their original patio area, or even garage, into a California room.

It's easy to think that these breezy outdoor living spaces were dreamed up in the Golden State.

But Hazlitt says they owe their origin to southern Europe, where residents of Italy, Greece and Spain have been adding open-air living spaces to their homes for centuries.

Typically, these rooms were extensions of the house, with the roof and exterior walls or walls of the house being part of the structure.

These structures migrated to the United States about 25 years ago, first landing in Florida and then crossing the country to become what is known today as the California Room.

Of course, you'll find them in coastal states like California, but also in Louisiana, South Carolina, Texas, and even as far north as Maine.

Given the current demand for outdoor living spaces, their popularity is likely to spread from here.

The California room plays on the love of the outdoors, but it allows homeowners to add some traditional comforts to their outdoor activities.

Some homeowners will add a full bar, TV, and even carpet to their California rooms, making them like living rooms where they can enjoy fresh air and spectacular views.

The cost of adding a California room to your property will depend on size, amenities and, of course, the cost of construction in your area.

Typically, rooms start at about $20,000, Hazlett says, and the cost will increase from there depending on your needs and how you decorate.

If you're on the fence about whether to add a room to your property, consider this.

If done correctly, you could see the value of your home skyrocket and entice buyers to spend the extra money for a place to enjoy outdoor living without having to soak in the heat of the sun or endure rain, Bishop said.

"If there are other homes in the neighborhood that have California rooms or other upscale amenities, such as pergolas or outdoor kitchens attached to the home, homeowners could add 80-100% of the construction cost to their property value," Bishop said.