Loft insulation advice

[vonsworld]

My house was built in the 60's and there are no vents in the facias or soffits. The original loft insulation between the joists goes right to the edge and meets the felt below the tiles.

So it appears no air can get into the loft from under the eaves and during the winter I have noticed some condensation.

Is this a common problem in 60's housing?

I'd like to add an extra 200mm of insulation but what would be the best way to improve the ventilation please?

I could add felt vents to open up a gap between the joints in the felt and let in more air. Would this be enough?

Thanks
Robin

 

[Wayners]

Stick board around edges to stop insulation blocking off air.
Fit vents in soffit. You can drill hole and push in a vents. Watch out for asbestos boards through.
Get some roof vents fitted in tiles.
Add more insulation.