Deleterious Materials

Question 1

What is a deleterious material?

Answer 1

Deleterious materials were materials that were used in good fath at the time but have been proven to be a risk to buildings.

Question 2

Describe the issues with Calcium Silicate brickwork.

Answer 2

Used in lieu of concrete, often for inner leafs of cavity walls, it is susceptibel to shrinking but can perform well if used correctly.

Question 3

Describe the issues with Chloride Concrete Additives.

Answer 3

Used as an accelerator in concrete but can reduce the passivity in damp conditions.

Question 4

Describe the issues with High Alumina Cement.

Answer 4

Mainly used in pre-cast roof and floor beams produced during the 1950s-70s and is susceptible to loss of strength in hot or humid conditions.

Question 5

Described the issues with using Sea Dredged Aggregates.

Answer 5

Sea Dregeded Aggregates may contain salts which can risk corroding the reinforcement. Proper washing and treatment of the aggregate can mitigate this.

Question 6

Describe the issues with Woodwool Slabs.

Answer 6

Used as deckings for flat roofs, but can reduced fire resistance and lose strength.