Beyond the Blueprint: Amber Lewis on the Art and Engineering of Custom Bunk Rooms

In the world of high-end interior design, few features capture the imagination quite like the built-in bunk room. It is a space that suggests summer camp nostalgia, cozy family gatherings, and the ultimate sleepover fantasy. Yet, according to Amber Lewis, the powerhouse designer behind Amber Interiors, there is a significant chasm between the whimsical aesthetic of a bunk room and the rigorous reality of its construction. With the release of her third monograph, Interiors, hitting bookshelves today, Lewis is pulling back the curtain on the industry, aiming to demystify the complex, often arduous process that goes into creating these highly functional, custom-designed spaces.

Lewis, who has built a reputation for her signature "California cool" aesthetic, argues that the role of an interior designer is frequently misunderstood. She posits that her team acts as a hybrid of builder, architect, therapist, and project manager, all while navigating the technical hurdles of high-level residential construction. While her new book offers a deep dive into her professional philosophy, it is her exploration of the bunk room that serves as a masterclass in balancing form and function. For Lewis, a bunk room is not merely a piece of furniture; it is a serious architectural commitment that demands deep foresight and professional-grade engineering.

The Engineering Imperative

The primary misconception about custom bunk rooms, Lewis notes, is that they are a simple, weekend-ready DIY project. In truth, they represent a significant investment in permanent millwork. When a designer or homeowner decides to stack sleeping surfaces, they are dealing with massive weight distribution issues. A standard, store-bought bunk is designed to support a certain load, but a custom built-in is an entirely different beast.

"If the bed is not going to have support on all four corners, you really have to engineer the interior of it, probably with steel and concrete, and that would have to go tie back into the actual wall itself," Lewis explains. She emphasizes that at the end of the day, a robust, custom bunk system—including the framing, the mattress, the bedding, and the occupants—can easily weigh 1,000 pounds. This is why she insists that homeowners avoid hiring a general contractor who specializes in "cute" woodwork and instead seek out teams with genuine structural engineering expertise. The structural integrity of the bunks is not a place to look for budget savings; it is the fundamental foundation of the entire room.

Navigating the Cost of Customization

When it comes to the financial reality of these projects, Lewis is candid: custom built-in bunks are almost invariably more expensive than their store-bought counterparts. The cost is driven by the necessity for bespoke millwork, professional engineering, and the installation of custom staircases or ladders. "When you’re building anything, there are costs associated," Lewis notes. "As soon as you start doing custom millwork, and engineering support, and building stairs, your budget is blown."

For those who love the look of a built-in bunk but find the price tag prohibitive, Lewis suggests a strategic alternative. Rather than commissioning a fully custom, site-built structure, she recommends purchasing high-quality, pre-fabricated bunk sets and customizing the surroundings. By painting these pieces to match the wall color or selecting bespoke bedding that ties into the room’s broader upholstery scheme, homeowners can achieve the "built-in" look without the full cost of bespoke construction. It is a practical compromise that allows for a high-end finish while keeping the structural risks and costs under control.

Designing for Adult Guests and Long-Term Utility

A common thread in Lewis’s work is the realization that bunk rooms are rarely just for children. While they are often conceived as a solution for large families, the majority of her clients actually request them for housing guests. This shift in demographic has fundamentally changed how she approaches the design process.

"It’s for housing guests," she says. "Queen beds on the bottom, sometimes a twin on top, sometimes it’s double queens, sometimes it’s a full." She even notes that while she hasn’t yet been asked to design a bunk room featuring king-sized beds, she views the challenge as an inevitable future project.

To cater to adults, the design must feel sophisticated and private. Lewis suggests installing curtains around each bunk—not just for the aesthetic charm of a "cozy nook," but for the practical benefits of privacy and light-blocking. In a room where multiple people might be sharing space, the ability to close off one’s sleeping area is a luxury. Furthermore, she emphasizes the importance of thoughtful amenities: every bed should have dedicated charging ports, reading lamps, and even personal Bluetooth speakers for white noise. These small, considered details elevate the bunk room from a utilitarian dormitory to a high-end guest experience.

Planning for the Evolution of the Home

One of the most critical aspects of designing a bunk room is the recognition that the occupants will eventually outgrow the standard twin mattress. Lewis speaks from personal experience, noting that her own 17-year-old daughter is now significantly taller than she is. If she had built a small, restrictive bed a decade ago, she would now be faced with a costly and inconvenient renovation.

Her advice to clients is to plan for the future by opting for twin XL mattresses or larger, even if the primary users are currently small children. "Trust me," she says. "If I had built her a tiny little bunk bed, I would have been really bummed." Additionally, she advocates for the use of removable rails. These provide safety for younger children but can be easily taken down as the occupant matures, extending the life of the furniture and saving the homeowner from having to replace the entire structure in a few years’ time.

Addressing Safety and Maintenance

Beyond the structural build, the daily usability of a bunk room is a major consideration. The act of getting in and out of the top bunk is the most obvious safety concern, but it is often overlooked in the design phase. Lewis emphasizes that while vertical ladders can save space, they are significantly more dangerous to navigate, especially in the dark. She recommends wrapping ladder rungs in leather or rope to provide texture and grip, or, if the footprint allows, installing a narrow staircase. A staircase provides the safest and most reliable way for occupants of any age to ascend and descend.

Finally, there is the issue of maintenance—or what Lewis laughingly refers to as the "pain in the ass" factor. Making a bed on a top bunk is a notoriously difficult chore that often discourages owners from using the space. To mitigate this, Lewis advises against heavy, "fluffy" bedding on the upper levels. She prefers a simple, streamlined approach, such as using a single throw blanket over the sheets.

To further improve the experience, she often incorporates a "master off switch" near the bedroom door, allowing the last person out of the room to extinguish every reading light in the space without having to scale each ladder. By anticipating the physical realities of maintenance and operation, Lewis ensures that the rooms she designs are not just visually striking, but genuinely practical for the people who will actually use them. Through this marriage of high-level engineering and thoughtful, human-centric design, she proves that the humble bunk room can be one of the most sophisticated and enduring features in a home.