To find out if you have enough insulation in the attic, measure the thickness of the insulation. If it's less than the equivalent of the R-30 (about 10 to 13 inches), you could probably benefit by adding more. Before insulating, seal any air leaks and repair the roof and other necessary repairs. If it is located in a conditioned part of the house, remember to also insulate and seal the access to the attic. Proper insulation of cathedral-type roofs will allow the roof temperature to be kept closer to room temperature, providing an even distribution of temperature throughout the house.
Cathedral-style roofs must provide space between the roof terrace and the roof of the house to achieve adequate insulation and ventilation. This can be achieved by using lattice beams, scissor lattice frames or sufficiently large beams. For example, cathedral-style ceilings built with 2 x 12 inch beams have space for standard 10 inch columns. (R-30) and ventilation.
Cathedral-type roofs without ventilation (warm roof design) are also an option. The warm roof design allows more insulation to be installed in the roof cavity, as the need for a ventilation gap is eliminated. It is important that the roof cavity is completely isolated from the conditioned space below to prevent moisture from entering and roof degradation. Insulating a tile in an existing house can be expensive and annoying, but if the slab of the house is cold, it is possible to dig around the perimeter of the house and install insulation, usually of foam sheets.
In most parts of the United States, insulating the outer edge of a slab can reduce heating bills by 10% to 20%. Office of Energy Efficiency and Renewable Energy, Forrestal Building, 1000 Independence Avenue, SWWashington, DC 20585. It is better to place insulating panels under the roof structure, while mineral wool can be inserted between the ceiling beams. The roofs of cathedrals are partially parallel to the roof, so they require a certain level of insulation, and the rest must be roof insulation. It's a little easier to work with vaulted ceilings; these ceilings don't necessarily need ceiling insulation because there is an air gap separating the living room from the ceiling.
I had limited knowledge about roof and ceiling insulation, so I called on an expert to show me if it was better to insulate the roof or roof and the advantages and disadvantages of each. Insulating the roof is a good idea, but insulating the roof instead of the roof has some disadvantages.
