Return to the Old House Forum | Post a Follow-Up

Cleaning Asbestos Cement board siding

Posted by fpgoa (My Page) on
Tue, Jun 18, 13 at 15:01

We have a late 1950's split level in suburban NJ with what I believe has been referred to as asbestos board cement siding. One of my elderly neighbors (original owner) recently had a fly by night painting service come to his identical house and did some sort of powerwash/ sanding process and then paint it and it looks terrible. It has shiny spots, rub spots (visible from the street) and it basically looks like a fly by night job.

We are not well off enough to get new siding nor painting but want to get the green "shotgun spore" build up off of the north side of the house and clean various other dirt which makes it less than spotless white around. My wife wants the guy who cleans out our gutters to powerwash the house while I am concerned that powerwashing might chip or be too abrasive on the ancient siding.
What is the best way to clean this style of siding?

Follow-Up Postings:

RE: Cleaning Asbestos Cement board siding

I'd obviously avoid any abrasive processes, but a gentle scrubbing with a RV brush would probably get it fairly clean. Use a house-wash attachment to your hose to apply the cleanser, scrub, rinse. Look for a cleanser that announces its particular effect on mildew. If the siding is still stained after physically scrubbing, maybe look into an application of bleach.
Oh, yeah, protect the plants from the cleanser and definitely from any bleach.

RE: Cleaning Asbestos Cement board siding

I'd try what Casey has suggested in an inconspicuous spot. If it works do the whole surface.

But start at the bottom, not the top. Sounds counter-intuitive because you'll be washing the upper ick down over the lower, already- cleaned walls. But the lower walls be wet and the stuff from above will slide right off. If you start at the top, you may get the stuff running down and making stains. Finish up each vertical section with a thorough rinse from the top down.

Work vertically in sections about 4 to 6 feet wide. That is pretty much as far as you can reach from side to side once you're up on a ladder.

There are all kinds of scrub brushes: flat, rectangular floor ones, ones with splayed-out bristles (good for cleaning the under-edge of a siding lap); narrow ones which work particularly well in the right angle between boards, etc. Even tooth and nail brushes may come in handy. Be prepared to try an assortment. I have washed a few houses by hand, and I find the OXO brushes pretty comfortable in the hand, but start with what you already have.

When rinsing or using the hose be particularly mindful of not spraying up at too narrow an angle which might drive water under the laps. Try to get the water on more at a right angle, where it will just cascade down.

If you're going to work on a ladder you might try getting one of those U-shaped metal stand-offs. They make it easy to scrub against a house. You can take the cleaning solution up in a bucket and just hang it over the ladder rung with a paint bucket hook.

You're going to get wet doing this, wear old clothes, and do it on a warm day.



RE: Cleaning Asbestos Cement board siding

An 'acid brush' on a painter's pole should do fine.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Old House Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here