on a traditional pitched roof construction,where is heat insulation usually provided?
The insulation is always placed in the rafters, leaving the rest of the attic space ventilated. That's why it's so important to cover every opening with screen to keep birds and animals out.
Generally, the insulation is blown in loose fiberglass to around 14 inches -- R 38, between the ceiling joists. Radiant barrier roof decking is often used in conjunction with this method, along with excellent attic ventilation to allow heat to escape. Sometimes, with foam insulation in new construction, the foam is installed between rafters, to create air conditioned attic. This is much more expensive, but if done right, can result in greatly lowered energy consumption. This method requires outside air having a way to get into the home, requires special AC and heat equipment, and if the wall insulation and window package aren't up to snuff, much of the effect is lost, resulting in wasted money -- tens of thousands of dollars, literally.
On the ceiling.Paper side down to help protect against moister.
