Wickes DIY stores sell a twin pack, (1) Underfelt, (2) Top layer both self adhesive, First you must strip off the old felt completly, then prime the surface with the adhesive required for the project.
Lay the underfelt after the primer has dried, make sure you lay it right as you will not move it once it has touched the surface to be covered, repeat with the top felt no primer req'd for this part as both are self adhesive. Dont forget to allow sufficent amount to overlap at the ends ready for dressing on completion.
Wickes have a D.I.Y sheet for the correct procedure.
I have used it for 2 flat roofs successfully.Ask in store for details.
Malc., November 2009
