Hi Dave,
Welcome to the forum.
You should accept any problems, poor quality workmanship or defects in your new home.
It is not impossible to build a defect-free new home. All that is needed is care, enough time and the desire and drive for perfection.
Be aware Barratt are better than most, but don't be too quick to say "yes" to Q1 on the NHBC survey form you will be sent after 8 weeks of moving in. You can use this to your advantage to get things sorted out. Once the form has been sent you will find Barratt less accommodating!
Get your new home professionally snagged and inspected before you move in.
I suggest you call Tim Fee at Snagging Inspections 07768 900200