You can buy air ducts that staple to the inside of your roof above the eave vents and fit between the rafters.
Should you insulate between roof rafters.
You can add insulation to the floor.
The rafters are joined together by a horizontal ridge board at the top and tied together by ceiling joists at the bottom.
Insulating the rafter space will give you a warm loft.
If you re considering turning your attic into conditioned storage or living space it s worth changing tactics to insulate between the rafters and wall joists instead of the floor.
Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing.
The ones i ve used are made of styrofoam and iirc they cost around 2.
This means insulating between or below the sloping beams that form the construction and support a sloping roof.
Usually you will certainly fill the insulation blower with the insulation and blow it between the attic floor joists.
If your attic is going to be converted into livable space then you will need to insulate the roof rafters.
On new build or replacement pitched roofs the ideal build up would be insulation fitted over and then between the rafters giving a big boost for airtightness image credit.
Install ventilation baffles into the space between the rafters before you install the insulation usually by stapling into place.
Hire a pro to install spray foam insulation.
The current trend is for a warm roof where insulation is installed between the rafters thereby keeping the roof timbers warm.
You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters.
A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel.
The will hold open an air gap of approximately 1 inch to allow airflow past a layer of insulation.
You can use rigid foam panels or do as tom silva does with nearly all houses these days.
Make sure it is flush against the wood as also a 1 inch gap can create a 20 percent heating loss.
In order to avoid damage to the roof deck you should insulate ceilings to create an air barrier between the living space and an unfinished attic or airspace underneath the roof deck.