NHBC Concrete & Drainage

What is the minimum depth allowed for Foundations?

• 1000mm

• 450mm

• 150mm

• 300mm

Give two examples of good practice regarding Foundation

• Vertical sides, Horizontal bottom

• Water and debris in foundation

• Roots and water in foundation

What is the main problem with water in foundations?

• No problem

• Concrete can cope with water

• It helps concrete to set

• It could lead to a soft spot

  Concrete is diluted

Is it acceptable to use bricks to use bricks to support foundation reinforcement?

• Yes

• No

What are the effects of trees on shrinkable soils?

• They hydrate the soil when wet

• Its fine to build close to trees

• Trees have no adverse effects on soil

Heave precautions are to counteract?

• Soil swelling

• Tree roots

• Too much concrete

Heave protection should be placed?

• On internal walls

• On external walls

• Either internal or external walls

• On the bottom of the foundation

In addition, for piles, pier and beam foundations and ground improvement techniques, check

• §Spacing

• §Alignment

• §Position in relation to the proposed superstructure

Rockers should be a maximum of ?mm from the sub structure

• 150mm

• 200mm

• 1m

• 500mm

The minimum gradient for a 100mm drainage pipe should be?

• 1:150

• 1:40

• 1:100

• 1:80