Straight bonding of roof tiles

[Anishrag]

I provided some tiles to my builder to use on my roof. They were the laescandella planum roof tiles



I looked at the roof yesterday and found that they have been laying it straight bonded (not staggered). Mine is a low pitch roof (17.5 degrees) so I'm worried about the problems this would cause.
The manual for the planum says that the tile should be laid broken bond. But looking at the tiles it does look like there are some water diversion channels under the crack.

I have the following questions:
1. How likely is this to cause me a problem? Is it something I should definitely get fixed or could it work ok?
2. Is it reasonable for me to assume that in the absence of any contradicting instructions they should be laid broken bond? I haven't seen any houses with flat roof tiles that are straight bonded so I would assume that regular custom is to lay them broken bond. Would that be correct?

Would appreciate your comments!

Thanks!

 

[catlad]

If you provided the tiles then it would have been your responsibility to give the builder the fixing guidelines, did you provide the tile clips also?

 

[Anishrag]

Thanks for the reply!
Yes, I wish I had provided fixing guidelines.

I did provide tile clips.

I'm hoping the tiles are ok like this. I do see that some interlocking tiles can be ok if laid this way. And from looking at the tiles it does seem like it may be ok.

 

[Makie]

As long as the headlap is done correctly you will be fine. It just looks much better when half-bonded.

 

[noseall]

Most concrete interlocking tiles are laid straight nick with the exception of the odd few (zero profile). Yours would have looked better bonded, but not much. Where on Gods gracious earth did you find those?

 

[Anishrag]

Thanks for your replies. Luckily, I don't care too much about look. It's not a very visible roof.

I got the tiles at Sig roofing. I don't know much about roof tiles but they don't seem too uncommon. Distributed by classic natural slate in Ireland.