Can someone tell me if it is worth it to insulate a basement of a house. I have read that it is a waste of money. is this true?
That depends on the use and design of the basement.
Insulating a walkout used as a living/play space makes sense.
I have a fully underground basement(with a cellar type entrance into my wood shop) that does not need insulated, it is quite cool all summer and 72 degrees in the winter.
I finished a huge basement in a friends house and insulated part of it for better, more even temperature control.
If your basement is heated or cooled by design or default, then the walls need to be insulated.
Even if the walls are nearly completely underground, they still need to be insulated because a considerable amount of energy is lost through the foundation walls into the soil.
Insulating the walls of even an underground basement always makes sense because lost energy means money wasted on unecessary heating and cooling.
If your basement contains no furnaces, boilers or similar devices that condition the space, then the ceiling of the basement should be insulated.
I put a 1.5 inchs of foam on my basement wall raised my basement temp 10 deg in the winter and nice and cool in the summer money well spent