AC power plugs and sockets are devices that allow electrically operated equipment to be connected to the primary alternating current (AC) power supply in a building.
Building insulation is any object in a building used as insulation for any purpose.
In Euclidean plane geometry, a rectangle is a quadrilateral with four right angles.
Scaffolding, also called scaffold or staging, is a temporary structure used to support a work crew and materials to aid in the construction, maintenance and repair of buildings, bridges and all other man made structures.
Soundproofing is any means of reducing the sound pressure with respect to a specified sound source and receptor.