“For bedrooms with slanted ceilings, I recommend a low headboard, or no headboard,” she says. “If the ceiling slope begins too low for a headboard, choose a low, minimal bed, like a platform ...

Because the bathroom is only 4.5×5.5 feet, with a sloped ceiling that makes it feel even smaller, Janette had to get a little creative when it came to the shower area.

And though some might find slanted ceilings a decorating challenge, Mr. Phillips roots for them. They “need to be embraced and celebrated, especially in second-story spaces where roof lines ...