Roofer criticised our new roof - how serious are his concerns? Pics in post

[Sarah100]

A roofer who is also a surveyor was helping out on an unrelated, non-roofing job and raised a lot of issues with our 6-month-old roof. Are these problems I should raise with the original roofers and/or fix ourselves while there's scaffold? The render has cracked so I'll be raising that at the least. Or, are these minor quibbles that aren't worth worrying about?  Any views would be much appreciated, thanks.

 

According to the critical roofer:

 

The tiles (49s) haven’t been nailed. He says because we’re within 1.5 miles of the (South) coast, British Standards say every other course should be nailed;

 

They’ve put timber in two places at the valley to support tiles. This shouldn’t have needed to be done. One of the tiles has already dropped. The timber will rot and then more tiles will drop. The roofer who did the job says the batten tilt under the lower eaves is fully treated and won't rot;

 

 

 

 

 

The felt and breathable membrane extend over the gutter - he says the felt should have started higher up and will rot and water will be soaked up under the roof. The roofers fitted felt, breathable membrane and TLX Gold insulation;

 

 

 

 

Some of the lead hasn't had patination, harming the lifespan. He said the horizontal lead has had patination but the vertical hasn't in the picture below;

 

 

There should be lead straps securing the lead flashing, there’s minimal headlap – he estimates 50mm -, and they should have used 38mm nails instead of 50mm, with the risk of piercing the insulation (which did happen). The roofer who did the job says that’s wrong and 50mm is the right size.

 

The whole roof:

 

 

 

Thanks again

 

Edited February 26 by Sarah100
Got rid of unnecessary detail