For anyone who has murmured enviously over This Old House reruns or cursed a crooked apartment doorframe, the National Building Museum hosts the “Festival of the Building Arts,” an exposition of home improvement and building crafts. Today, artisans from all trades demonstrate their skills and offer advice on everything from stained glass to bricklaying, gilding and stenciling to wallpapering, plastering to roofing. The festival includes a “construction machinery petting zoo,” a rare chance to have a live backhoe feed from your hands, as well as a participatory concert of musical saws and wrenches. From 10 a.m.-4 p.m. at the National Building Museum, 401 F St. NW. FREE. (202) 272-2448. (Andrew Webster)