What is class H soil?

Class “H”: a highly reactive clay. We see this site class around 20% of the time. H class soils have been broken into two groups. H2 soils are more reactive than H1 soils so the footings for a H2 site are going to need to be stiffer than if you have a Class H1 or Class M soil.

Can you build on H1 soil?

For ‘highly’ and ‘extremely’ reactive sites and problem sites (i.e. Class H1, H2, E or P), a structural engineer will need to do a special assessment and advise on how to safely build a house without the risk of damage due to soil movement. Moisture variations tend to be lower at greater depth in clay soils.

Can you build on H2 soil?

AS2870 says waffle slabs can be used on reactive clay soils – even Class H2 soils – with some construction style limits: Timber frame: Yes. Articulated Brick Veneer: Yes.

What does H1 soil test mean?

Moderately Reactive Clay or Silt: Sites that may experience moderate ground movement. H1. Ys = 40 to 60 mm. Highly Reactive Clay: Sites that may experience high amounts of ground movement.

Is Class P soil bad?

Class P soil means a serious problem. Class Problem soil does not easily fall into one of the soil types, and requires a specialised solution from a structural engineer.

What is an H slab?

Class A – This denotes very ‘stable’ ground – mostly sand and rock, not affected by moisture. Class S – Slightly reactive soil, slight movement due to moisture. Class M – Moderately reactive soil, moderate movement due to moisture. Class H – Highly reactive soil, a high amount of movement due to moisture.

Is p class soil bad?

What is the best soil type to build a house on?

Loam
Loam: An ideal soil type for home construction, loam consists of silt, sand and clay. Dark and dry, loam is crumbly and soft to the touch. Because it is evenly balanced, loam is able to hold water at a more balanced rate.

What kind of slab do I need for a class M site?

Most Class S sites only require a basic slab with concrete beam footings at the edges of the slab. Class M means that the soil found on your clay or silt site is moderately reactive. The movement expected from this type of soil is 20-40mm. Class M sites require a stiffened slab with cross beams in the slab.

What kind of clay do you use for a house slab?

Reactive clays are classed as follows: Class “M”: a moderately reactive clay. We see this site classification about 35% of the time. Ground movement isn’t ‘too bad’ and house slabs can easily be designed for this soil. Ground surface can move vertically between 20mm and 40mm between wet and dry conditions (seasons).

What’s the difference between Class H1 and H2 soil?

Class H1 defines soils with high ground movement, measured from 40mm to 60mm. Class H2 corresponds to clay soils with very high ground movement of 60-75mm. Any construction projects over Class H and more reactive soils need to be done in tandem with a structural engineer.

How does Class H2 affect a waffle slab?

The Class H2 ground surface pushes on the underside of the waffle slab and the waffle slab lifts. Well, it tries to.