Washing Siding Before Painting

wessieball · Post by **wessieball** » Fri Oct 05, 2007 12:33 am

I'm going to be painting two sides of my house on Monday and need to give the siding a nice wash beforehand. Everything is primed and caulked but I really don't want to use a pressure washer for fear of 1) using too little pressure and not getting off the grime 2) using too much pressure and introducing moisture to the underside of the siding. Also, I'm not a big fan of TSP and considering my current paint job is only 4 years old don't see the need to use a heavy duty cleaner/degreaser on it.

So...my plan was to use a garden hose to wet the surface and brush the siding by hand. I figure this way I can really see the work up close and possibly do a better job cleaning. But...what can I use instead of TSP as a light detergent to get some of the grime off?

jade mortimer · Post by **jade mortimer** » Fri Oct 05, 2007 8:22 am

can i just say i REALLY appreciate your efforts to clean your house in a sensitive and labor intensive manner? it is heartening to know that there are still people out there who are willing to invest time to do the right thing!!!

how about using a garden pump type sprayer using water and simple green concentrate? if you have mold you may want to use something different...if you're just removing dirt and grime, the simple green will work...make sure you rinse thoroughly....here's wishing you a nice sunny day(s) for your work.......

...jade

HB · Post by HB » Fri Oct 05, 2007 8:35 am

You could use Dawn liquid or maybe even a laundry detergent.

Put the soapy mix in a garden sprayer to shoot it on the walls and then scrub them down with a stiff bristle brush.

Rinse with the hose and try not to shoot water up under the siding.

Be careful painting this time of year - you can't really get an early start because there's so much dew in the mornings and you can't work very much past about 3 pm cause it cools off so quickly in the envenings.

At least here in SEPA that's how it is.

Good Luck.

HB

lrkrgrrl · Post by **lrkrgrrl** » Fri Oct 05, 2007 10:39 am

I would NOT use laundry detergent, dish soap or simple green. Use a no-rinse cleaner designed for pre-paint cleaning. Like Dirtex. you should be able to find it in a hardware store. You can also look for "TSP Free" or other TSP substitutes, again, in the hardware or paint store. Soilax was my old favorite, but it's no longer available. (I usually rinse anyway, but they say you don't have to.)

Foaming detergents are too likely to leave some sort of residue, which will impede your paint adhesion.

jade mortimer · Post by **jade mortimer** » Fri Oct 05, 2007 11:13 am

on a scale of 1 to 10, how confused are you now?

i am cleaning moldy gasket trim on my garage door, the gasket is some sort of flexible plastic (intalled by po)...i'm using tsp and bleach and am cleaning on my driveway where there is moss growing because it doesn't get sunlight til late in the day...so i am cleaning the gasket and driveway at the same time...i prefer to use the least caustic, most productive products but in this case, nothing else has worked but bleach....

the simple green does need to be rinsed but, after a mild scrubbing, i think it's best to rinse off the dirt and whatever cleaner you choose to use....sg is marketed as biodegradeable and non-toxic....

.....jade

HB · Post by HB » Fri Oct 05, 2007 3:05 pm

lrkrgrrl wrote:Foaming detergents are too likely to leave some sort of residue, which will impede your paint adhesion.

I did not know that!

Thanks for the tip!

HB

ChrisF · Post by **ChrisF** » Sun Oct 07, 2007 11:00 am

When I painted my house about 4 years ago, I used a brush on a REALLY long 3-piece extension pole and Soilax. The pole was able to extend to 27 feet, so I was able to just about reach everywhere. So far, so good....no paint adhesion issues.

Didn't know that Soilax had been discontinued though....bummer, it worked REALLY well.

Sombreuil_Mongrel · Post by **Sombreuil_Mongrel** » Sun Oct 07, 2007 1:20 pm

Hi,
You said that "everything is primed and caulked". Soooooo...., if you mean "everything" (full primer on all surfaces) then I'd just wipe down with a microfiber cloth after a light (220) sanding, and paint. If there are really dirty spots like bird flop, use a wet microfiber cloth. You really, really don't want to completely wet down a primed house. It can cause additional paint peeling, and you'll have problems.
If, OTOH, you have just "spot primed", and now wish to proceed with a full prime coat, then go ahead and wash away to your heart's content. Just let it dry fully, then prime and try to get the finish coats on before it gets dirty again.
Casey

PRB · Post by **PRB** » Mon Oct 08, 2007 2:24 pm

When I did my siding this year, all I used was a brush and water, no soap (I was concerned about leaving behind residue that would affect the paint adherence). The clapboards had been covered with aluminum for 30+ years and were absolutely filthy with grime, but a scrubbing brush with nice stiff bristles did the trick.

bellevue · Post by **bellevue** » Sat Oct 13, 2007 10:10 pm

at least according to their own packaging, "oxygen bleach" (OxoClean or OxyBrite) is good for this and does not leave residue. i have found it works on many applications, but i admit i have not tried it on siding.