The best attic insulation practices for energy efficiency
The best best insulation practices are more important now than ever because of high energy bills in a tough economy. Insulating roofs, attics, and floors makes a very big difference in efficiency because of the thickness of the insulation.
Home insulation methods have gotten so much better because of the high R-values of modern insulation. Many homes that were built before the 60's were really poor on insulation. Most walls were 4-inches with light insulation inside.
As prices for electricity raised because of higher demand, people started building better homes using more insulation out of necessity. Insulating attics with an R-value of at least 30 suddenly became a great way to reduce energy bills by 50%.
Homeowners started insulating crawl spaces and adding extra insulation to walls and pipes that were letting heat escape.
Many roofs can fit R-38 insulation between the rafters. The attic floors can fit R-30 between the floor joists. There are many ideas for better efficiency that I don't cover here, but you can find more info at most government sites on saving energy.
This is especially important if you live in a heavily populated area like New York City where electricity rates are often double than they are in more rural areas.
There is a special type of insulation for every part of the house.
Most floors over a crawlspace can fit R-30 between the joists as well. This seems like a lot of expense for insulation, but it will save a lot of money in the long run.
It's also important to insulate in between headers. Many people don't remember to do this and around doors and windows are often the places where efficiency is the lowest.