Before Boston designer Patricia McDonagh got her hands on this 1,000-square-foot condo just off Memorial Drive in Cambridge, "it was newish," she says, "but unpolished. It lacked warmth."

Since she was working on a budget, her makeover of the loft had a lot to do with paint and stain and natural light and inexpensive furniture. The once dull, undefined space now feels like a calm retreat that's both airy and cozy. Here's how she did it.