Hi, you will get a much better finish if you put on the undercoat then gloss and lightly rub down between the two using a tack cloth after sanding to make sure you get all the tiny bits of dust off. I would always go for the oil based ones too as I find they are much better. If you don't use undercoat and just use normal gloss then the colour under the gloss will bleed through in a very short time.
Hi, sorry I forgot to put you don't need undercoat when using one coat stuff. As you can probably see from my previous answer I don't like one coat very much lol. Proper paint for proper job.
I may give it a go. If the wood was previously a different colour I wouldnt be tempted to use it as per Shedmans comments about bleeding over.
Histiorically I've always used the undercoat/gloss combination but I'm doing the hall/stairs/landing. Thats 5 doors, all the skirting, and the bannister.
Boolders................ try using a little 100mm radiator roller on the doors. Does flat surfaces in a tenth of the time. Try a short-haired gloss roller head.
Thanks for the tip Builder. I have a rad roller. May not come in use on the doors as they are panelled but would be good use on the large bannister area. (Is 'bannister' the right term? - its the large wood area that separates the stairs from the landing)
Ooh .. That's a no no in the period building trade, although some builders use it to speed up a job.
You cannot beat oil-based primer/undercoat on exterior timber .. and it does not fetch up the grain in many woods like acrylic does.
My tip .. use a primer and then a good quality gloss .. not one coat or non-drip. Ultimately a better finish.