Can you lay roofing felt on top of roofing felt?

Flat roofing problems - MyBuilder

Questions You Should Ask The Roofing Company – Satoshi United
When felting over any old felt you can use a bitten primer to get a proper fix, some felts are also a 3 layer system allowing them to go over old felt, however if he has quoted for old felt to be removed then that is what he should have done. Any old felt roof needs to be completely taken up and re boarded.

Will roofing felt stop rain?

Can Roofing Felt Get Wet? | Home Guides | SF Gate

Redding & Red Bluff Roofing Contractor - (530) 356-0686
Roofing felt can get wet and still maintain its integrity, as long as it is not exposed to the elements for more than a few days. It will break down in sunlight and with large amounts of ongoing moisture. ... If the felt is still wet, it may rip when shingles are installed.

Do I need a permit to put on a new roof?

How Do I Apply for a Roofing Permit? | Networx

Watertite roofing contractor | CMS For You
Permits are required for most new roofs, re-roofs and major roof repair jobs, but many cities don't require them for minor repairs or replacements of less than 100 square feet (one "square") of roofing area.