In this picture, you can see where someone has reinforced a squeaking floor with some additional support. Squeaking floors and spongy spots are not only irritating, but they are also a sign that your home is struggling with crawlspace moisture and wood rot. Another important sign is that musty smell that you catch when you open or close a window or door. That smell is actually air being drawn up out of the damp crawlspace into the rest of the house and it's a sign that your home needs some crawlspace encapsulation and repair right away!