Layers Of Dust
It may seem rather obvious, but if your attic has gone untouched for a long time and has been building up more and more dust along the way, this is an indication it needs clearing out. It may seem harmless, especially out of sight like it is, but that isn't true! There are vents in your attic to circulate air and that means the dust can be picked up and brought into them, not only clogging the vent but also polluting the air as well. The blocked-up vent means your energy is being wasted, as air has to force through it slowly, and the pollution means that you and your family's health is at risk. Particularly for anyone with breathing conditions already, such as asthma, it's extremely important to have this taken care of.
Foul Odors Near The Attic
If you notice a nasty smell when you're near your attic's entrance, that's usually a sign of trouble. There are two usual causes for this, either a pest infestation or mold. Rodents may be making themselves at home in your attic, encouraged in by all the dust, and leaving behind their waste in the process. They might even wind up trapped and die there. In either case, disease will also be involved with either of these things, posing more health trouble for your family. Mold is also a hazard, though for a different reason. Its spores are dangerous if inhaled, and on top of that it will eat away at all sorts of things in your attic from the structure itself to your belongings. A cleaning is a good first step to stopping both of these issues!
Allergies Persisting Indoors
Related to both of the previous signs, if you find that your allergies or any other similar issues continue to be just as bad indoors as they are outdoors, you may have an issue with your attic's cleanliness. Dust, insect waste, mold spores, all sorts of substances related to a dirty attic can be aggravating your allergies and causing you to suffer through the symptoms even indoors. Getting it cleared out can take care of the problem!