Possible Clues:

• Joint groove
• Pop round to see what's above the skirting board
• Father finds party by the border along the wall
• Differently decorated lower part of an inside wall
• Groove of carpentry
• Middle part of a pedestal
• Decorative wall border
• Differently finished lower part of an interior wall
• What '...' may mean: Abbr
• Differently finished lower part of an inside wall