Extension roof - is this 'standard' practice?

[Gareth1974]

The builders are finishing off the roof on our extension. Noticed that on one aspect of the roof, they've reused old tiles from the house to partially tile the roof, instead of using new tiles for the whole extension. We've queried this, but have been told it's what's normally done. Is it?

[Gareth1974]

Drumroll said:

Why do you think it is a problem?

Whilst it looks a bit odd (although I see nothing wrong with it) give it time and you won't notice a difference.

I think it's problem because it looks odd.