If you experience extensive condensation in the future chances are the insulation has detached from the top plate.
How to properly insulate old porch roof metal roof.
Traditionally condensation is managed by insulating the metal roof so that the panel temperature never reaches the dew point.
Polyurethane spray foam metal roof insulation in order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam.
Insulating with spray foam insulation.
Cut each sheet to the desired size using a utility knife then fasten it in place using staples or adhesive.
Secure the insulation to the top plate of the wall with a staple gun so that cold air cannot come up between the top plate and the insulation.
Leave gaps between panels.
It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer.
A pair of ceiling fans is also being considered.
Avoids nails or screws which could penetrate the metal roof and cause leaks.
Cut panels on roof.
But for insulation i would tack up some 1 foil faced rigid foam sheeting and then cover it with wafer board or plywood which you could paint or whatever.
It would go hand in hand with applying some sort of paneling to the interior side of the roof to hide the insulation and provide a bit more of a finished look.
The foil will reflect the heat from the roof and the foam will keep any cool air down you will also be able to keep the airspace which is absolutely essential with the steel roofing.
Staple plastic or foam baffles to the roof sheathing near the eaves to keep the material away.
Thats why people use the ceramic deck screws.
Make all cuts to the foam panels on the roof for more accurate cuts and quicker placement.
If you re willing to invest some more consider an insulated porch roof.
For the same reason insulation shouldn t touch the roof s underside.
This is often accomplished using vinyl backed fiberglass insulation to prevent humid air from coming into contact with the cooler metal roof which may be at or below the dew point.
Use rigid foam insulation to cover wider spans of roof sheathing between joists.
Large foam insulation sheets can be nailed directly against the floor above or held in place by chicken wire or other metal elements with the facing against the underfloor.
What s the best approach to insulating this.
Before doing any work with the metal roof insulation you should have it brought up onto the roof.
The insulation should fit snugly to prevent air from getting through.