On Sep 18, 6:29*pm, harry wrote:
On Sep 18, 10:26*am, "AL_n" wrote:

I want to remove the bottom row of cement ties on my pitched roof, in order
to lay a strip of damp proof membrane under the lower edge of the felt
which has disintegrated where it projects from under the tiles.

The tiles are fairly larhge (I guess about 40cm x 50 cm or so). Each tile
is nailed, at the top, to a betten. How do I extract the nail, when it is
covered by the tile above? And how do I replace the nail when restoring the
tile to its original position, after the felt work is done?

Many thanks,

Al

There is a tool called a ripper for this. *Long thin blade with hookon
the endshovesupunder the tile and a sharp jerk cuts/breaks/pulls out
the nail.
There are special latching gadgets to put the tiles back.

http://www.tooled-up.com/MicroCatego...=134&MCID=1790

There is special plastic gadgets to fix your perished felt too. *They
have it in screwfix.

http://www.screwfix.com/p/felt-suppo...ack-of-5/36622

Ripper or slate rip as its called in the roofing trade is totaly
usesless in removing nails in concrete tiles. Its sole use is for
slates.