WASHINGTON — For the past month, 24 local design firms have been working to transform a newly constructed $4.895 million farmhouse-style home into a showcase of classic and modern design — and now the pros are ready to show off their work.

On April 12, the eighth annual DC Design House will open its doors to the public; tours will run through May 10, and all ticket proceeds benefit Children’s National Health System.

The 8,869-square-foot, three-level home, in the Mackall Farms community in McLean, Virginia, boasts a gourmet kitchen, a butler’s pantry, four bedrooms — including a guest suite and a master suite — a loggia, an art aficionado lounge and a library.

Since the first event in 2008, the DC Design House, now a 501(c) 3 nonprofit entity, has attracted more than 55,000 visitors and has raised more than $1 million for Children’s National Health System.