Painting woodwork, water based over oil?

[robodelfy]

Hi

I want to paint all the woodwork in my 3 bedroom victorian terraced house. I have no idea if the current woodwork is oil or water based, is there an easy way to find out?

I've used oil in the past at other places as it was all I knew. But it discolours so much, I was hoping to switch to water based from now on to keep it white

If it is oil based currently (which is likely), whats the best method to change to water based? Do I need to sand it all down a lot, or just give it a key? Do I need a special primer, and then how many coats of water based paint?

Any recommendations of brands?

Any advice would be great

 

[Sunshine32]

Hi,

As someone who has removed and is still removing 91 years of paint layers from a late 1920s house, i’d say your best bet to find out what the current layer of paint is made out of is to do a methylated and white spirit test.

If the current paint layer is water based, and you rub it with some elbow grease with a cloth soaked in methylated spirits you will see some of the paint left on the cloth.

If the current paint layer is oil based, and you wipe over it with a cloth soaked in white spirit, it will just remove any dust and/or grime from the paint, it shouldn’t leave any paint residue on the cloth.

 

[johnny2007]

Sand it to give it a key and paint over.
Modern paints grip on.

 

[Sunshine32]

A few tips on how to get a good finish on woodwork:

Remove any flaking or damaged paint from the woodwork by stripping with a heat gun or sanding.

Use a good 2 part epoxy filler to fill any holes or dents and sand back so it’s flush.

Sand all the woodwork back using 120 or 180 grit as your last sand before any paint is applied.

Prime your woodwork first and don’t be tempted to just paint without doing the prep.

Sand in between coats of primer and undercoat and top coat using 240 grit and do it lightly.

 

[robodelfy]

A few tips on how to get a good finish on woodwork:

Remove any flaking or damaged paint from the woodwork by stripping with a heat gun or sanding.

Use a good 2 part epoxy filler to fill any holes or dents and sand back so it’s flush.

Sand all the woodwork back using 120 or 180 grit as your last sand before any paint is applied.

Prime your woodwork first and don’t be tempted to just paint without doing the prep.

Sand in between coats of primer and undercoat and top coat using 240 grit and do it lightly.

Thanks, and what about painting water based over gloss? Do you need a primer even if you sand it back?

 

[Sunshine32]

I strip all my wood back to bare wood. I’ve had to do this because there are so many layers of unstable paint on the wood that stripping back to bare was my only option as I wanted the best finish I could achieve. A lot of the wood detailing was getting lost due to heavy layers of paint.

The woodwork in your property is probably oil based, most people use gloss or satinwood. Personally, gloss has caused me more issues than it’s solved so I stick to water-based paints. There will be a lot of people on here who will disagree with me on that but I find it easier to rectify if it gets damaged.

If it’s oil based paint and you want to change to water-based paint without stripping back to bare, yes I would suggest you use a suitable primer. This will help stabilise the new paint

 

[sxturbo]

if its painted already, sand it back wipe clean with meths and paint, use a decent trade paint,

zinsser is good, Crown fast flow, and a lot of people rave about johnstones also

 

[robodelfy]

if its painted already, sand it back wipe clean with meths and paint, use a decent trade paint,

zinsser is good, Crown fast flow, and a lot of people rave about johnstones also

Thanks, so if I'm using water based over gloss, and doing what you said do I need to prime it after sanding and cleaning?

 

[Sunshine32]

Thanks, so if I'm using water based over gloss, and doing what you said do I need to prime it after sanding and cleaning?

I did already answer this but you seem to not be convinced. You would benefit from getting over to the Screwfix community forum and posting there. Astramax is the master of all this stuff. With luck, he’ll answer your post.

 

[robodelfy]

I did already answer this but you seem to not be convinced. You would benefit from getting over to the Screwfix community forum and posting there. Astramax is the master of all this stuff. With luck, he’ll answer your post.

Sorry I totally missed your other answer! Ok thanks for your help

 

[sxturbo]

Thanks, so if I'm using water based over gloss, and doing what you said do I need to prime it after sanding and cleaning?

generally speaking water based doesnt react with gloss thats sanded and cleaned, a lot of modern paints, most notably trade paints dont require a primer on a previously painted surface.

that said it would usually be good practice to paint a test area to confirm no reaction takes place.

my whole house was painted with oil based gloss when i moved in, and i have 2x rooms left to paint. All the woodwork was replaced in 1990 by the previous owners and only have a couple of layers of paint.