Author Sheri Koones believes that prefab houses (or “prefabulous,” as she calls them) are the homes of the future. She’s written five books about them.

In the new “Prefabulous Small Houses” (The Taunton Press), Koones focuses on modestly sized homes and cottages, between 350 square feet and 2,500 square feet.

“It is definitely possible to live large but on a small footprint without cramping your style or budget,” she said in an interview.

Compared to the basic modular homes of a decade ago, Koones says, these prefab residences are more elegant, eco-friendly and economical. Unlike traditional, on-site home building, they can be put up in a matter of days or weeks.

The book profiles 32 homes across the country and explains some of the latest technologies. In a foreword, Robert Redford extols the ecological virtues of going prefab.

Excerpts from Koones’ interview with The Associated Press:

AP: How did this book come about?

KOONES: I’ve been writing about prefab construction for a long time. If you’re going to write about energy-efficient, sustainable homes, it really has to be prefab. The technology has come so incredibly far in recent years. And the more I traveled and looked around, the more I saw that there was a trend toward living smaller, and focusing on travel and other things instead of pouring all your time and resources into your home. Today, almost anything that can be built on-site can be built prefab. In Japan, most of the houses are prefabricated, and in Australia many of them are. We’re slowly going in that direction, too.

AP: The homes featured in your book look very expensive. How economical are small, prefab homes?

KOONES: Prefab houses can cost from 5 percent to 15 percent less than an on-site built house. And we know that building prefab saves time and energy both in the construction process and also in terms of maintenance. You wouldn’t want someone to dump a bunch of car parts in your driveway and build a car there, so why would you want a home built that way? It’s so wasteful.

AP: What design elements do these homes use to help them feel comfortable and roomy despite their diminutive size?

KOONES: High ceilings, limited hallways and rooms used for multiple purposes are elements shared by many of the homes featured in this book. The emphasis is on living well as opposed to living big.