Painting sash window question

22 Apr 2012
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United Kingdom
Hi, I'm preparing to paint interior of sash window and as a DIY beginner want to check not missing anything. Any help appreciated!

The window was previously painted but paint was cracking really badly so I've ended up stripping all the paint off and sanding smooth. There's a couple of small holes in wood which I've got some Ronseal wood filler to fill.

In terms of next steps do I just need to fill the holes with wood filler, then apply some knot blocker on the knots (I've got some got some Rustins white knotting for this), then paint on wood primer (have some Johnstone's wood primer for new & bare timber), then paint on top coats (Dulux satinwood)?

I'm just wondering because one thing I read said cracking of paint on window frame near glass is often due to not creating a proper seal between the wood and the glass. It didn't explain further so I'm not sure if this just meant failing to create a proper paint layer or if there some other product I should be applying that I'm missing.

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I presume your using undercoat, as you only mentioned topcoat satinwood.
On bare timber especially windows i would give two coats undercoat and one topcoat, the undercoat is the body of the paint, finish coat is the dressing!
I presume you mean seal the window, in which case you want to get paint onto the glass just a couple of mm and slightly overlap each coat. If your a newbie i suggest masking tape for clean lines.
Unless the windows are fairly new, I doubt you are getting any problems with sap seeping from any knots, but if they are exposed on bare wood then no harm in knotting them.
If you just have some small fine cracks close to the glass then consider using a little fine surface filler for that. Glass and timber expand and contract in their own way so minor cracks do occur.

IF you are using Dulux Satinwood, then it does say on the tin that it is self undercoating and give 2 coats, but, it also says to undercoat if darker colours will show through. Now in my book, as handyman has said, using an undercoat is what an experienced dec will do just to ensure that a good base is in place before a top coat. Also, adding an undercoat will allow you to check all is well with the paintwork and adjust as necessasary
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Thanks very much. Yeah I hadn't bought any undercoat because the satinwood tin said not needed but given the hours it's taken me to get the old paint off I'm not in mood to take any chances or shortcuts now! I'll get some undercoat as you suggest. Appreciate the responses.

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