I WANT TO DOT & DAB AN OLD EXTERNAL BRICK FACE WALL THAT IS NOW AN INTERNAL BETWEEN HOUSES DO I NEED TO COVER WITH PVA? THE EXTERNAL WALL IS NOW A PARTY WALL BETWEEN TWO HOUSES AS HAVE PUT ANOTHER HOUSE ON THE SIDE. I WANT TO DOT AND DAB THIS WALL HOWEVER HAVE NOT DONE THIS TO EXTERNAL BRICK BEF...
