The code allows for insulation directly to the underside of the structural roof sheathing providing the unvented attic is contained completely within the building thermal envelope this language is in both the residential and commercial codes.
Why insulate the underside of roof sheathing in an attic.
All of that said the specific problems you describe point to poor coverage and lack of a vapor retarder.
Senior engineer manager at icynene john broniek makes the case for the unvented attic assembly and why insulating the underside of the roof makes sense.
Staple plastic or foam baffles to the roof sheathing near the eaves to keep the material away.
Mold growing on the sheathing in your attic is a serious problem that shouldn t be ignored.
But the best solution is actually to insulate both the attic floor and the underside of the roof.
Seal any roof vents into the parts of the attic that are not heated.
This occurs when the temperature of the sheathing drops below the dew point creating a thin layer of moisture on the substrate.
Mold on attic sheathing.
Leave a clear space between the top of the insulation and the underside of the roof sheathing to allow for roof ventilation.
Mold growth on attic roof sheathing is a common issue in cool climates such as the pacific northwest.
At the same time the areas below the roof benefit from increased comfort both during the winter and the.
On the landing the view of the remainder of the attic was limited by duct work and equipment.
In the vast majority of cases the mold growth is caused by condensation.
You may also insulate your roof to help regulate the temperature in an attic that is a part of your living space.
However this set up causes a different problem.
In most cases it should be possible to insulate each rafter space all the way down to the eaves and over the top of the exterior wall.
Materials commonly used for the insulation of the roof deck include.
The quest for greater energy efficiency in buildings has led to increasing interest and need for insulation improvements in hvac equipment more airtight construction new materials and assemblies.
The presence of mold inside your home even if it s in an unused place such as the attic can cause.
If the nasty old insulation was left on the floor of the attic the thermal envelope would be defined.
In this way you prevent the heat from the rooms below escaping to the attic rooms above.
For the same reason insulation shouldn t touch the roof s underside.
Moving past the ducts i saw that there was insulation between the cathedral ceiling below and the sheathing for the roof.
Insulating the roof is a priority if the ceilings of your home happen to be part of the roof deck as is the case with cathedral ceilings.
In an attic configuration if same insulation depth is applied to the inner sheathing this design also reduces thermal bridging i e from additional thickness of rafter overspray.
The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow.