\version "2.12.3"

ledgerUp =
{
  s2
  \stopStaff
  \override Staff.StaffSymbol #'line-positions = #'(-4 -2 0 2 4 6)
  \startStaff
  s2
  \noBreak
  s2
  \stopStaff
  \revert Staff.StaffSymbol #'line-positions
  \startStaff
  s2
}

ledgerDown =
{
  s2
  \stopStaff
  \override Staff.StaffSymbol #'line-positions = #'(-6 -4 -2 0 2 4)
  \startStaff
  s1
  \stopStaff
  \revert Staff.StaffSymbol #'line-positions
  \startStaff
  s2
}

\new StaffGroup
<<
  {
    \ledgerUp \ledgerDown
    s1*4
    s1*4
    \ledgerUp \ledgerDown
    \ledgerUp \ledgerDown
    \ledgerUp \ledgerDown
    \ledgerUp \ledgerDown
    s1*4
    s1*4
  }

  {
    s1*4
    s1*4
    \ledgerUp \ledgerDown
    \ledgerUp \ledgerDown
    \ledgerDown \ledgerUp
    s1*4
    s1*4
    \ledgerUp \ledgerDown
    \ledgerUp \ledgerDown
  }

  {
    s1*4
    \ledgerUp \ledgerDown
    s1*4
    s1*4
    s1*4
    \ledgerUp \ledgerDown
    \ledgerDown \ledgerUp
    \ledgerUp \ledgerDown
    \ledgerDown \ledgerUp
  }
>>

\layout
{
  \context
  {
    \Staff
    \override BarLine #'stencil = ##f
  }
}