.house_thermo
{
  position: relative;
  top: 0;
  left: 0;
  height: 149px;
  width: 164px;
  margin: 0 auto;
  background-color: transparent;
}

.house_thermo .house_full,
.house_thermo .house_empty
{
  width: 100%;
  top: 0; 
  left: 0;
  overflow: hidden;
}

.house_empty
{
  position: absolute;
  z-index: 3;
  background: transparent url() no-repeat top left;
}

.house_full
{
  position: relative;
  height: 100%;
  z-index: 2;
  background: transparent url() no-repeat top left;
}