if vessels have been designed in 2008 and have not been fabricated yet and fabrication has to be done in year 2009. In such case is it mandatory to include Addendum 08, since it has been issued. I have done my calculations in 2008 based on 2007 edition only.

Check the date when you have received the order. If you receive the order before Addenda 2008 became mandatory (i.e. 1st January 2009), then you can use Edition 2007 based design for Code Stamped Vessel.

Mukesh

A kind of similar question. I have made a calculation according to ASME VIII 2007 version. The client says he wants to have the calculation according to ASME VIII 2004 edition. It's a new built vessel.
In my opinion I have to use 2007 though. The notified body however says it's still allowed to use the 2004 edition.
Is there anybody who can shed any more light on this topic? (using older code versions for new built vessels)

If client insist then you can design with older version of Code. But if it is Code stamped vessel then you will have to design with latest mandatory version of the Code.

Mukesh