The exposure on the first course of slate must instead be.
Starter course slate roof.
If the slate has been sorted and the roof marked out properly then laying the slate is straight forward.
An 8 5 exposure on the first course of slates then would only leave a headlap of 1 5 on the starter course a mis take.
If the starter course is laid with the face side up the installer is inexperienced and it s likely there are additional mistakes in the roof installation.
This is a very common mistake inadequate headlap on the starter course.
As well starter shingles have a sealant strip and when positioned correctly the sealant strip will be on the top surface and at the lowest edge of the roof.
One can tell immediately if a slate installer is experienced or not by looking at the starter course.
If you have selected iko s armourshake shingles for your roof you will need to use iko armour starter.
If there are no starter shingles along the perimeter edge it would be extremely difficult to try to slide starter shingles in under the first course due to the fact the shingles are nailed along the tar line which is approximately 5 5 to 6 inches above the edge of the shingle.
1 the starter course is incorrectly installed face up.
Used in conjunction with our standard leading edge plus starter armour starter provides extra thickness and protection between the shingle tabs of the first course of armourshake ensuring a beautiful roof appearance from bottom to top.
However the recent trend is to forklift a pallet on to the scaffold and lay the slates straight out of the pallet without grading.
At the eave the starters provide a simple way to cover the joints between the finish shingles in the first course ensuring complete water shedding roof coverage.
Slate starter courses.
You can read about starter courses on slate roofs in traditional roofing 5.
Before you run out and start chalking 8 inch lines up a roof for 20 inch slates let me remind you that the starter course first course and often second course will be chalked on a different measurement.