Painting over Varnished Wood

ruie, Apr 11, 2:17pm
x1
We are wanting to paint our internal rimu window surrounds which have previously been polyurethaned. They are currently cracked & water stained. The original coating is a clear polyurethane.
Would appreciate comments from those who have previously faced this issue & what you used as a sealer undercoat to prepare the surface for a water based enamel top coat.
Did you sand? Did you use a sealer such as Zinsser Cover Stain or Resene Smooth Surface Sealer or just a more standard sealer primer undercoat such as British Paints 4in1?

eljayv, Apr 11, 3:26pm
We did all our skirting boards with Zinzer some years ago very happy with the result I believe Dulux now have a similar product called something like 1 step

emeargg, Apr 11, 7:12pm
Resene smooth surface sealer

sanders4, Apr 13, 8:29pm
Sand with a 60 grit paper and then seal with pigmented sealer. Then apply 2 top coats of either acrylic enamel or if in full sun I would use an oil based finish - the smell is worth the longevity of the finish!

tygertung, Apr 13, 10:49pm
I have had poor results using water based paints on windows frames as it tends to go mouldy with moisture. Use oil based. Easier to get a nice finish too.

Resene supergloss goes on nice and isn't very smelly.

jsimons12, Apr 14, 9:18am
I would go to Mitre10 Bunnings & ask about silicone sealants that can be sanded & painted. You might be able to fill in any cracks first with a different product then seal over the top, or use the silicone sealant for everything.
There is a paintable silcone used for bathrooms which I don't know the name of.
I believe this could also work (Give them a call):
https://www.housepaint.co.nz/product/sealer-ultra-4l-waterproof-concrete-wood-etc/?utm_source=Google%20Shopping&utm_campaign=HousePaint&utm_medium=cpc&utm_term=729&gclid=Cj0KCQjwgtWDBhDZARIsADEKwgNRXyAsombKB-qY8GcMAY7nUoMcQ1vVTTZAJAaZGB3-ZeXTcEUB8NEaAsfmEALw_wcB

ruie, Apr 15, 3:02pm
Thanks to everyone for your suggestions & comments. I've ended up using the Zinsser Cover Coat which is adhering & covering well.

wine-o-clock, Apr 15, 4:19pm
It;s just me, but I wouldn't paint over native wood

sla11, Jul 31, 5:02pm
I thought Resene Sealer better than Zinsser - better cover. No show through of underneath marks, stains.