To understand this, we have to understand their nature first.
The insects, bugs are the unwanted creatures that infiltrate our homes. They are not so dangerous or harmful as a big carnivore for sure, but they are stinky, gross, and dirty at t most of the time. Not to mention they are extremely infectious. Hence, the easier thing to do is to keep them away as much as we can.
Now it is widely observed that the infiltration becomes maximum in the summer seasons.
The answer is simple: temperature.
There are many kinds of research and studies that are done by scientists. Here, it was also understood that insects have an ”optimum temperature”. In that particular temperature, the growth of them exceeds extremely.
It’s like the that whenever the temperature of the surrounding rises above this certain given temperature, the population of the insects grow rapidly.
With the descend of winter, and the coming of spring, The temperature started increasing distinctly. In this condition, the bugs reach their optimum temperatures. Thus the number of bugs in a particular area grows super fast henceforth.
However, contrasting to this, a low-temperature threshold also exists that kills the growth rate of the insects. It is calculated to be approximately 59°F.
Scientifically, bugs like spiders and other insects are ectothermic. This means that they accumulate heat from the surroundings. Not only that they reflect the same surrounding temperature conditions in which they live. Hence, they will always try to restore their original optimum temperature conditions. So according to the surrounding temperature they decide to come out or stay in their holes. Obviously, in summer their temperature exceeds far more than the optimum temperature. Hence, they come indoors to restore all of that. That is the reason why we see that there are too many insects in our houses in summer.