Your main concern with paint on a new door is movement of the wood and knots. If you have a choice of doors try and get the least knotty. You can treat them with knot sealer but can't work miracles.
10 years ago I'd have suggested Dulux Weathershield Primer which was a blue liquid most painters swore by, they had to stop making it because it was killing dolphins (fair enough). The acrylic one doesn't work anywhere near as well. Zinnser stain seal + All coat on top is a pretty good contemporary solution. You have a fancy colour so that will cost more and not last as long. Most coloured exterior gloss paint is guaranteed for 8 years, white for 10. Eggshell finishes and darker colours don't last as long as 8 years normally.
Of course a shrunken head peering out from there would stop any draught and discourage anyone looking in the shed. Pricey though.
Your main concern with paint on a new door is movement of the wood and knots. If you have a choice of doors try and get the least knotty. You can treat them with knot sealer but can't work miracles.
10 years ago I'd have suggested Dulux Weathershield Primer which was a blue liquid most painters swore by, they had to stop making it because it was killing dolphins (fair enough). The acrylic one doesn't work anywhere near as well. Zinnser stain seal + All coat on top is a pretty good contemporary solution. You have a fancy colour so that will cost more and not last as long. Most coloured exterior gloss paint is guaranteed for 8 years, white for 10. Eggshell finishes and darker colours don't last as long as 8 years normally.
Of course a shrunken head peering out from there would stop any draught and discourage anyone looking in the shed. Pricey though.