Carter provides sound advice.
How high does wood siding need to be above earth.
If the adjacent ground is concrete such as part of a patio or a sidewalk it still requires the same clearance as bare earth.
And also make sure the grade falls away from the foundation to be specific the 2015 international residential code irc requires the foundation to be 4 inches above the finished grade when covered by a masonry veneer or 6 inches elsewhere.
Having your siding too close to the ground is just asking for trouble.
Masonry veneer ledge 4in above earth wood sill 6in min.
The closer to the grade the sooner your siding will deteriorate.
Which also implies the higher the siding is above the grade the more likely your siding will stay intact withstanding any moisture problems you may incur without actual flooding situations.
That means if you place the siding 6 inches above the ground you get a 70 percent on the test.
As its name lap implies an upper siding board laps over the board below it by 1 to 2 inches.
Otherwise it needs to be protected either by being a naturally durable wood species or preservative treated.
Keep the foundation well above grade.
In addition wood used in construction of perma nent structures and located nearer than 6 inches 152 mm to earth shall be treated wood or wood of natural resistance to decay as de.
Protection of wood against deterioration as set forth in the previous sections for specified appli cations is required.
Any clearance is better than none.
Mike the building code here in the usa used to say that wood siding must be 6 inches above grade.
Wood siding stucco vinyl brick all siding should ideally have at least 6 to 8 inches clearance above the ground.
Most lap siding is beveled meaning that the bottom edge is thicker than the top.
This requirement is not just to prevent damage to the siding it serves a couple of other functions as well.
Concrete and masonry foundation walls shall extend above the finished grade adjacent to the foundation at all points a minimum of 4 inches 102 mm where masonry veneer is used and a minimum of 6 inches 152 mm elsewhere.
Realize the building code is a set of minimum standards.
Maintaining proper clearances reduces access to wood structures behind the siding by wood destroying insects or damage from water that might.
My code check actually states it this way.
Siding materials need proper clearances between finish grade and the siding regardless the type of siding.