G
Gable
The most common type of roof where two sections of roof meet in a point. The triangular section of wall where it meets a sloping roof.
Gable fillets
Thin strips of timber fixed along the verge of a gable roof of a garden shed.
Galvanised
Zinc-coated.
Gang
The outlet or set of terminals in a switch or socket. Two-gang switches allow two lights to be controlled from one switch position. Two-gang sockets have two outlets for plugs. Three-gang and four-gang sockets are also available.
Gasket
Used to seal joints to prevent gas or liquid escaping.
Gatevalve
On/off control operated manually to allow or prohibit the flow of water in low-pressure pipework.
Gland nut
A gland nut screws into the top of the headgear of a rising spindle tap. It is the highest nut on the spindle.
Glaze
A clear liquid used in decorating. Paint is added to the glaze and then it is applied to a wall where different paint effects can be achieved using brushes, sponges, rags etc.
Glazing points
Found in windows and picture frames, these metal inserts are pushed in underneath the putty to hold the glass to the sash or frame.
Gloss
A decorative paint which produces a sheen when dry.
Grain
The direction of fibres or patterning in wood.
Gravity system
A system for heating and circulating water that operates on the principle of hot water rising and cold water descending. Because hot water is lighter than cold water, the hot water from a boiler rises up to the cylinder and the heavier cooler water drops back to the boiler. With this type of system it is not possible to have heating without hot water.
Grommet
A plastic or rubber ring inserted into a hole or eyelet for reinforcement or to protect cables.
Grout
A compound used to fill the gaps between ceramic tiles.