Pitched roof, fibre cement slate - is this acceptable work quality?

[S1llyB1lly]

So, I have undertaken a ground floor extension. The roof consists of two parts - a flat deck and pitched sides left and right, at about 23 degrees or so, nothing overly complex.

I chose Marley Eternit Thrutone fibre cement slate. I also bought copper rivets, 65mm galvanised wire nails for battens and 30mm copper clouts for the slates. I handed these (and some other) materials to the builder and left.

I came back to this (images attached) and would like an opinion on whether these are minor things or a serious / potential to develop into a serious issue over time:

Things I have spotted (I am no expert so may have missed things):

1. One of the aluminium soakers is facing the wrong way up. Soakers have been attached with copper clout nails at one end to battens. I thought soakers were not meant to be nailed in?

2. Most of the slates are completely flat, but one or two are sticking up slightly (see attached image). I will ask that this is rectified.

3. If you look carefully, you will see that the slates do not rest on the battens but instead each course actually shoots over / the batten. Also, the roofer has not used the holes already punched through the tiles but has created his own. I asked why, he said "because of the low pitch, I am doing my own clout holes as the slates will have a 150mm overlap as opposed to 110mm."

Are these minor things not worth worrying about or not?

 

[chappers]

Nothing to worry about there all those issues are minor or not important at all.
The only thing I would probably rectify there is the double slates, at the end they can kick up like yours have, as you can't rivet at the centre, I would have put another whole slate in there and then a cut into the abutment. But in reality the flashing will probably hold that down and you won't have any weathering issues, its just aesthetics really. Soakers should be nailed as they can slip otherwise, so long as they are nailed above the lap, also if increasing the headlap you will have to punch new nail holes, also doesn't really matter to the integrity of the roof that the slates have gone past the head battens just means that if anyone ever had to rip them out with a slate ripper that they wouldn't be able to as they are nailed twice with the second set of nails being the nails of the course above

 

[vinn]

Presumably you are going to install some cover flashing above the soakers?
Given the fragile nature of your slates (& the awkward access) it would have been best practice to install cover flashing before slating.

Where your first soaker meets the gutter: do you have a Kick-out piece installed or is that something else that I can see?
You definitely need a Kick-out at that point - at both LH & RH abutments. You can make them yourself if you cant locate a suppliers.

 

[S1llyB1lly]

Thank you for the comments folks!

I just had to Google kick out flashing to get a better understanding of what that is.

I can see the benefit of but is it really necessary? If so, I am guessing lots of tiles will have to come off to get to the bottom.

I have a gutter running the length of the roof...and, yes, the plan is for him to have some code 4 flashing on top of the soakers.

 

[vinn]

What you cannot afford is water running down into that inaccessible space below the gutter.
Only you on site - with a water test? - can determine if you need Kick-outs.
You dont have to lift slates, you can slide the Kick-out behind and below and pin to the wall.
Sometimes the first soaker can be manipulated to act as a Kick-out.

 

[chappers]

or just bend out your cover flashing slightly to make sure it directs into the gutter.

 

[vinn]

In the arrangement above, bending the cover flashing wont make any difference - because where the soakers meet the abutment a Secret Gutter of sorts is formed, and water will run down the "gutter" below the cover flashing.

Bending the cover flashing will sometimes work where step & cover flashing is used on profiled tiles.

 

[chappers]

Maybe in severe weather situations you might get a bit. I have only just on Saturday started to take up a roof with exactly, this arrangement with a step & cover flashing over fibre cement slates at the abutment. The flashing I would say extended about 6-7"over the slates and underneath you can see the staining on the slates where the rain has run under the flashing and down and it hasn't penetrated more than 2-3" under the flashing. the only water that has run right down the abutment is that that has landed directly on top of the flashing and there is absolutely no staining on the wall to indicate that anything significant has missed the guttering.
Not saying it's technically correct but just the way it is.

 

[catlad]

Did you baton that roof out yourself because its a cockup
if the builder did it then I would be worried.

 

[vinn]

So thats what you are actually referring to from your first post above - step & cover flashing?
Why?
Step & cover flashing is obviously irrelevant to the soakers & slates in the photos.

Roof coverings are installed to deal with the most extreme conditions - using step and cover flashings on slate can lead to creep and other difficulties.
Its not just technically incorrect - its it will eventually leak wrong.

 

[chappers]

So thats what you are actually referring to from your first post above - step & cover flashing?
Why?
Step & cover flashing is obviously irrelevant to the soakers & slates in the photos.

Roof coverings are installed to deal with the most extreme conditions - using step and cover flashings on slate can lead to creep and other difficulties.
Its not just technically incorrect - its it will eventually leak wrong.

Why would you expect it to leak.
The roof I have just taken off the creep under the flashing has extended no more than 2-3" under the cover flashing and even if it had extended the whole way, how is it going to leak, the whole abutment is protected by soakers, the very worst that can happen is that water could run down and miss the very end of the gutter, but the actual reality of most situations is that the last soaker isn't actually so close to the wall as not to be able to direct any water into the gutter.
Have a look around you, you will see hundreds of slate roofs with step and cover flashings. over soakers

 

[S1llyB1lly]

Did you baton that roof out yourself because its a cockup
if the builder did it then I would be worried.

Hello, the builder did it Please advise what is wrong with it. I am quite worried now!

I appreciate that the overlap is more than standard, but is there anything else that is wrong?

 

[S1llyB1lly]

Right folks, an update (with pictures).

We discovered that the gutter was leaking (would have been handy to know this before doing the tiling first time around, but I didn't spot it). I sourced a replacement box gutter, but in order to get the old one out and new one in, tiles had to be taken off.

Anyway, builder popped tiles back on same day after gutter was installed, end result is as per pics.

The pitch is about 23 - 24 degrees or so, but for some reason whereas previously he did 6 rows / courses of tile with a larger overlap, this time, he has gone standard overlap and 5 rows?! I asked why the change, he said because that is what standard overlap is. I asked how far battens were spaced apart and he said approximately 9.5 inches...no idea what significance that is, however, as I am not a roofer.

Wish I had taken new batten pics, but I wasn't there when he was redoing tiles...anything serious to be worried about based on above / images? Code 4 lead step style flashing will be done at the sides...

 

[chappers]

looks about right. for 500x250 slates.
Normal head lap (amount slate covers the ones two courses below)at that pitch would be about 100mm and gauge( bottom of one slate to bottom of slate above ie batten gauge) would be about 200mm.
If gauge is right then headlap will follow.

 

[S1llyB1lly]

looks about right. for 500x250 slates.
Normal head lap (amount slate covers the ones two courses below)at that pitch would be about 100mm and gauge( bottom of one slate to bottom of slate above ie batten gauge) would be about 200mm.
If gauge is right then headlap will follow.

Ah, I think there is a problem - these are 600 x 300 slates, not 500 x 250 slates. But then again, is that such a big issue? There are 5 courses and the roof 'height' is 1.15m, 115 divided by 5 = 23cm = 9.1"

I will measure this evening dimensions and add them into thread. In the meantime, I found this in a Marley Eternit spec sheet (I am using Thrutone), so maybe the slightly larger batten gauge isn't so bad?