Clean ext. wall before painting?

I'd certainly hose it down if there is a coating of dirt or dust on it. I'd do it a couple of days before painting to let it dry well.

Brush with a little SnS and some bleach, rinse. Scrape loose paint. Let dry well.

Read any paint can, they require you to have a clean surface, paint wont adhere long on dirt and mold plus any warranty will not exist.

• Sand the spots where the discs were so they don't show through the new paint. * Caulk where needed. * I would use TSP (trisodium phosphate) instead of Spic 'n Span. SnS might not wash off completely.

Thanks to all for suggestions.

I forgot to mention that this wall has plants, up to 3' tall, growing right up against it. PITA to jam plastic back behind the plants, but gotta do it.

Question: Between the two suggestions for cleaning:

1. Spic 'n Span + bleach, then rinse

or

1. TSP , then rinse (I understood TSP needed very thorough rinsing as well. T/F?)

Which would be LESS damaging to the poor lil' plants? There is bound to be runoff; plastic won't protect entirely.

TIA

clipped

I don't think it matters what detergent you use, just get the chalked paint and dirt off. Bleach helps kill mildew so's new paint doesn't peel.

For plants, tie them up with some old pantyhose - cheap, disposable, don't damage the plants. Cover plants with plastic during washing, if you are worried. Plastic tarp will do fine, but don't leave on with hot sun shining, cause that can burn the plants. In my experience, bleach won't hurt plants as long as they are rinsed.

I don't know what's in S&S; that's why I recommended TSP. I know that TSP in small amounts won't hurt the plants. It washes off very easily, too. If S&S has detergent in it, it will take lots of rinsing to remove.

Instructions for deck cleaners always say to wet the plants down first, then cover them, then do the work, then uncover and wash them off. I do that with other types of chemicals, too.

It definitely helps to scrub it down with detergent and a strong bleach solution. The bleach will actually soften the old paint, and thereby make the new layer of paint adhere better.

- Logic316

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