Painting old weatherboard.

[saveasteading]

Your advice please.  The photo is the worst bit, randomly in the middle of my spiel.

I've painted this once personally, plus once by trusted workers and twice by professionals.

It's a big area, perhaps 200m2, so I'm keen to avoid high cost.

 

Some area are absolutely fine, being areas of replacement boards to a higher spec.

 

It needs doing again. Last year's heat caused more flaking than normal and I chose to scrape those bits off and let the heat carry on getting at it. Then the winter has released more layers and areas.

It has exposed some bare wood which will be either 10 or 90 years since first painted. Also sometimes  a yellowish layer and sometimes a clearly dirty, unprepared surface.

In other areas it all stays put.

My hunch is that letting blisters come off has released tensions that had allowed the surface to cling on to the dirty layers for many decades.

 

So today I have scraped more off and pressure washed it. 

I don't mind the indents where up to 10? Coats have been removed ("character").

Obv the manufacturers would like me to buy lots of expensive paint. But I'm wondering if the sheer thickness is an issue.

So do you think I can spray paint it for speed and economy. 1 or 2 coats? Perhaps the raw wood needs a brush of primer.

Where the timber is clearly cracked or eroded I guess it needs filling. First or after a coat of paint?

 

[Roger440]

Id imagine theres some impervous stuff on that?

 

Are you intending to paint over whats there? And what were you going to use?

 

[BotusBuild]

Have you got any good paint stripper in stock? Try it on a small area, then paint that bit with a good primer then appropriate outdoor paint.

 

Nitromors would be my goto for paint stripper.

[saveasteading]

1 hour ago, Roger440 said:

impervous stuff on that?

I know that the last 3 treatments are dulux wearhershield, undercoat then top.

No idea re the ancient history.

 

I'm hoping to be lazy/ efficient/ economical and paing stripping it all won't be that. Maybe locally.

[Roger440]

1 hour ago, saveasteading said:

I know that the last 3 treatments are dulux wearhershield, undercoat then top.

No idea re the ancient history.

 

I'm hoping to be lazy/ efficient/ economical and paing stripping it all won't be that. Maybe locally.

 

Nightmare stuff. Seals it up. Makes it rot.

 

Ideally, strip to bare wood, allow to dry then something like Bedec MSP. Sprayable too. No primer either.

 

Best thing about it is over long periods it sort of erodes away, bit like lime wash does, (but lasts much longer) so no prep required when repainting. Lots of work now, easy life in future. Depends on the long term view?

 

Edited Saturday at 22:59 by Roger440

[Alan Ambrose]

My favourite is Bedec barn paint. Suggest checking out ice blasting to get the soft stuff off then a coat or two of their barn paint. Roller or spray.

 

Should last 5-10 years and be easy to recoat. What’s the wood? Pine?

[saveasteading]

57 minutes ago, Alan Ambrose said:

wood? Pine?

Yes it is pine weatherboard. Some will be very old.

I can see one advantage in gloss paint, in that it seals the laps and reduces draughts plus keeps insects out.

The water blast had removed a lot of the loose stuff, even getting behind blisters and yanking them off.

Is bedec msp a barn paint to a higher spec?

I'll try this then I'll have to fill any 2mm gaps to keep the wasps out... they love the cavity.

[Roger440]

13 hours ago, saveasteading said:

Yes it is pine weatherboard. Some will be very old.

I can see one advantage in gloss paint, in that it seals the laps and reduces draughts plus keeps insects out.

The water blast had removed a lot of the loose stuff, even getting behind blisters and yanking them off.

Is bedec msp a barn paint to a higher spec?

I'll try this then I'll have to fill any 2mm gaps to keep the wasps out... they love the cavity.

 

Yes, MSP seems to be a slightly longer lived version of the barn paint. Or the barn paint is just the same stuff in a cheaper tin! Or watered down variant. Who knows?

 

MSP availble in gloss, satin or matt. Or the one i use, soft gloss.

 

Not sure it would fill a 2mm gap though.

 

[saveasteading]

Ai says this.

 

• Best Use Cases:
  • Bedec Barn Paint: Specifically for exterior barns, sheds, fences, cladding, and silos. It is designed to resist extreme weather, rot, and UV damage.
  • Bedec MSP: Best for a versatile "paint-anything" approach. Ideal for PVC windows, doors, cladding, metal railings, and radiators, both inside and out.