A common choice is drywall.
Rigid roof insulation panels.
Follow with a 2x4 frame wall and insulate it with batt insulation.
How to retrofit a roof to a high performance roof with insulating sheathing above the roof deck plus cavity insulation in roof framing remove existing roofing and non adhered roof underlayment.
R tech rigid foam insulation.
Apply a continuous air control membrane to existing roof sheathing or tape all joints between roof sheathing panels with an acrylic or butyl adhesive.
Keep in mind that any interior rigid insulating panel must be covered by a barrier.
R tech is available with factory adhered metallic reflective facers white facers or a combination of the two.
With this kind of roof the insulation follows the slope of the roof.
The panels provide a continuous energy efficient surface.
R tech panels are an engineered rigid insulation consisting of a superior closed cell lightweight and resilient expanded polystyrene eps with advanced polymeric laminate facers.
However most cathedral ceilings and low slope flat roofs are insulated roof assemblies.
It can be applied on the roof floor and walls and it s most widely used in structural insulated panels and insulated concrete forms.
Insulated roof assemblies can be vented or unvented.
Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency.
Eps is by far the most versatile of the three rigid insulation options.
There are lots of different ways to insulate this.
Insulated foam sheets are also used as an insulated sheathing underlayment for exterior siding.
Eps is also the most inexpensive of the three types of rigid foam insulation while also meeting the required building and energy codes.
A roof over a vented unconditioned attic does not need to include any insulation.
The most versatile of the three rigid insulation options used in roof wall floor below grade structural geofoam applications used most widely in insulated concrete forms and structural insulated panels highest average r value per dollar about 4 6 r per inch costs the least while meeting or exceeding all required building.