Fixed Price Contract but own Carpenter?

Hi All,
Could anyone shed some light on my dilemma. My Partner and I are sending out plans to tender for our new build. We are going fixed price contract. However, my brother is a carpenter who will fully qualify in June '07. He is excellent at his job and I want him to do our 1st and 2nd fittings only. Our roof is specilised Zinc, so he should not need to have anything to do with that. My partner protests that a Builder under fixed price contrat will not allow this. I say it's our house and surley other tradesmen go 'fixed' and do some work themselves and it's not a problem. The only problem that my occur is if anything need to be perpared for the roof, my brother does not want to do this.
Is this a problem or can it be sorted easily enough. I would appreciate anyone especially builders out there giving their opinion.

1st fix carpentry is all of the structural timber of the house - be it flooring joists, roof timbers or stud partitions. don't see how your brother could do this without doing any roof work !

probably better to get the builder to do all carpentry (including stairs) but excluding timber floors and skirting/architrave - your brother could do that then as that wouldn't delay the contractor in any way.

There is no problem at all with getting your brother to do any work, but you must note it and exclude it from your tender. The drawings and spec must be correct and if your brother consrtucts the roof to spec then the Zinc guy should have no problems. The builders will more than likley get in seperate subbies to do the timber work and zinc anyway so there would be 2 seperate trades

When you send out your tender, just exclude the work your brother is going to do… you should get a few quotes to keep them honest.

My advice is not to have “relations” work for you in a project this big, cos it can cause tension if you have any problems!
Your brother will be part of the equation; so you will have to ensure that he is available when the contractor is ready for him, thus not holding the project or the contractor up…
In addition you might have the blame scenario… if something goes wrong will the contractor be blaming your brother or visa versa?