Efflorescence in External Walls Is Caused by

question 7

Multiple Choice

Efflorescence in external walls is caused by

• A) The cement in the mortar
• B) Acid rain
• C) Soluble salts in the bricks
• D) Corrosion of the wall ties
• E) A chemical reaction between the bricks and the insulation

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Definitions:

Open-End Jaw

A wrench design featuring a U-shaped opening that grips two opposite sides of a nut or bolt head.

Box-End

A type of wrench or spanner with a closed loop that fits over the head of a bolt or nut, providing a secure grip for turning.

Allen Drivers

Tools with a hexagonal tip, used for turning screws or bolts with a matching hexagonal recess, commonly used in assembly and repair tasks.

Torx Drivers

Tools with a star-shaped tip used for tightening or loosening screws with a corresponding Torx head.