Painting over render

[astur]

Hello

I have a rendered house which was finished in Uni-Trowel Décor™ 333, which is an acrylic product.

The colour is vivid white. We then poured our driveway and we have some marks on some of the walls. I tried to touch them up with the render but you can see the spots where I’ve touched up in direct sunlight.

I need to either re-render the wall or paint the wall. I am thinking I’ll roll the wall in the same colour.
I don’t want to roll the whole front of the house, I will be stopping where the wall meets a corner or an expansion joint.

Has anyone ever rolled over this or a similar product? What type of paint did you use? What nap roller? Is there a noticeable difference between walls that are rolled vs walls that are not?

[r3nov8or]

I haven't rolled that product, but others, and undoubtedly it will look different eg gloss level, somewhat filling low points in the texture etc. The super fussy would paint the whole wall or render again, less fussy would touch up with vivid white and/or grow some strategic plants

[astur]

Thanks for the reply. Never thought about the texture and sheen. The marks are actually from using the gernie with too much force lol. It has left lines in the render, mainly where it has cleaned the dirt off etc. any tips for cleaning this off instead of going down the resurfacing road

[r3nov8or]

Hmmm lines in the render would be tricky. Maybe some photos might help (but yeah, the issue may not come up well on camera)

[rambunctious]

Thanks for the reply. Never thought about the texture and sheen. The marks are actually from using the gernie with too much force lol. It has left lines in the render, mainly where it has cleaned the dirt off etc. any tips for cleaning this off instead of going down the resurfacing road

Try a sugar soap wash first.
Use bucket and soft broom.
I would suggest you don't use a roller on it due to bubbles forming in the paint.
See it a lot here on the coast when walls repainted especially on unit blocks.
Best to spray it with acrylic low sheen.
That is what we did when we got tired of looking at the off white/cream rock coat.
Been painted for 4 years now with no sign of problems.

edit...By spray I mean an airless spray unit.

[ForeverYoung]

I have a rough render exterior, more like shot-crete/pebblecrete than render :(
anyway, what I learnt was, roller is a waste of time, and brush was time consuming and still couldn't get all the crevices.
next time (soon) I will spray.

the other thing I leant was to use a flat paint, mine is also vivid white.
(I did try a small spray can but they don't come in flat and the difference was very obvious).

[astur]

Thanks for the replies - sounds like painting is a no go. With the sugar soap, you just spray this stuff on and let it sit then scrub off? Is there any tricks with it? Just want to avoid wasting time if anyone has any tips lol

[rambunctious]

Thanks for the replies - sounds like painting is a no go. With the sugar soap, you just spray this stuff on and let it sit then scrub off? Is there any tricks with it? Just want to avoid wasting time if anyone has any tips lol

No you don't spray it.
Read the directions when you get it.
Mix it in a bucket of warm water and wash the wall.

[astur]

So I tried the sugar soap, that didn’t do anything. Also tried bleach and this algae killer product, both did nothing. I managed to take a photo. You can see the lines in the wall. I’m guessing it’s from the pressure washer/gernie. Any more tips or things I can try?

537727

[r3nov8or]

Umm, the suggestion above re sugar soap was to clean it before painting. In itself, it will do nothing else but clean.

Re the photo, it's nowhere near as bad as I'd envisaged. But again, maybe a photo doesn't do it justice

[mic-d]

The damage maybe doesn't come through in the photo as bad as reality, but if the photo is accurate I think I would be leaving it a few years to see if it mellows (or you do!). Alternatively, since you think the marks were caused by someone using a pressure sprayer, you could try using one with a patio cleaning head which will spread the cleaning over a larger area and perhaps feather in the damage. You would ideally try it on a small inconspicuous area and probably get a professional in to do it.