How to know how much to overlap tiles (so covering the holes), so I can work out how many I need?

[lozcozard]

My question was correct, I need to know how much to overlap the slate. No one could tell me! Once I saw the images it was obvious.

And you are correct in that I didn't have a clue, which is why I asked the question!

Now I know the answer, I have not purchased enough slate as the headlap I originally chose was not enough.

 

[lozcozard]

Something to add... many websites including the link above state the gauge/headlap would be recommended by the manufacturer. The problem I had was the roofing sales websites did not publish this. So I went to my local roofing merchant to take a look at tiles, and still no recommendation by the manufacturer. The roofing merchant couldn't tell me either. He laid out some tiles and starting messing with overlaps but at no point said what it should be on order for the bottom slate to rest on the next batten up. He did not seem like an expert roofer which makes sense as he just sells them. So I think that doesn't help the situation, when there is no recommended headlap publicised and yet thats what most websites say to check.

Anyway, I have sorted it now, I just wanted to say how I worked it out which was a lightbulb moment after seeing diagrams online with top tiles resting on the next batten. I think maybe its soooo obvious for roofers, but not being a roofer, it totally didn't occur to me to rest the tile on the batten above, not until I placed some tiles and saw the issue!

 

[mrrusty]

If you haven't started yet, here's a curve ball - think about using slate hooks. seen them used a fair bit in the SW - not so much elsewhere. I've found as a DIY slater they work very well because you don't have to worry about problems caused by nailing too hard. And get some decent slate shears/hole punch.