The humidity and temperature will influence the objects in the house. The attic will creak and it can be heard during the nights when it is very quiet. The metals will make noises when they get heated or cooled. The alterations in the temperature, drying of the moisture during the day time and dew in the night might result in creaking.
The creaking in the floors is due to the contraction and expansion of wood because of alterations in temperature. During winter, the drying of air inside the house with heat will also show impact on the creaking of wood. Wood generally tends to expand in warm temperatures even in the case of timber that is present in the attic region. In the absence of heat, the same wood tends to contract and makes creaking noise at that time.
The creaking noise might be because of the use of plywood for the floors. If there are many boards and nails that are used for fixing them under creaking might occur while walking on them. They can be raised all over the floor and the nails can be replaced with adhesive used for construction which is brought from the stores meant for home improvement. The glue that is applied will prevent the creaking sound as the movement of wood that is fixed as floor material will stop.
The creaking can also result when there are irregular gaps under the floor board. The creaking results when shims are added between the joists and floor boards. The floor that is made of only plywood instead of hard wood can be easily screwed to the joists. The joists can be identified under the plywood with the help of stud finder. After the joists are identified then the creaky board can be pressed down and screwed into the joist. This will avoid the creaky sound made by the floors. If the sound still persists, then the boards can be screwed down.