The slates are now fixed on the warehouse roof, these are self adhesive by Intentio. I don't know what the material is, something stronger than card or they would separate when you removed the backing paper, but it seemed to soak up paint like blotting paper. They were black as supplied, so I decided to spray the sheets a suitable grey colour then pick out a few slightly darker or lighter before fixing in place. However three sprays later and running out of the paint I'd mixed (and patience !) they were still a rather uneven colour, so I decided to start sticking them on the roof and sort out the colour later. They'll be painted again to get a more even colour when the ridge tiles are in place. In retrospect they should have been given a coat of primer first.
The adhesive has instant 'grab' and they have to be placed exactly right first time, so to keep them straight each row was placed against a steel ruler resting on two pins.
Near the top edge I used a couple of clamps to fix it in position. Where I couldn't fix the ruler in position in any way I taped the slates to the edge of the ruler with masking tape before removing the self adhesive backing, this keeps the slates straight and in line. The 'lead' in the valley between the two slopes is a couple of thin strips of Kapton Tape.
The top edge is a bit uneven and needs trimming before I fix the ridge tiles, which will be made from brass angle. Although the adhesive has instant grab it remains elastic and the slates can move if you're not careful when trimming in situ.
tbc
