Fire block devices for application to a wall component. The fire-block device can be a wall component that includes a fire-resistant material strip that expands in response to sufficient heat to create a fire-resistant barrier. In some applications, the fire-block wall component is positioned to extend lengthwise along and across a gap between wallboard members. The fire-block wall component may have a U-shaped central portion and a pair of side portions extending in opposite directions from the central portion. The fire-resistant material may be positioned on the central portion of the fire-block device. The central portion may be positioned within the gap such that the fire-resistant material expands in response to sufficient heat to create a fire-resistant barrier.