Power Washing and Roof Cleaning Forum

Maverick Contracting · Approved Exterior Cleaner

Cedar shake siding cleaning mix coverage

Ed Thompson · Approved Exterior Cleaner

If I'm reading right thats 3:1. That would be strong. That's almost roof strength. 9:1 should work fine and not as aggressive.

Maverick Contracting · Approved Exterior Cleaner

thanks Ed, I just dont want to come up short as this is an immense house but were only doing a small part to start that should take an hour or two to do and is remote to my local source. If I have to run out for more SH thats another hour+ lost incl. laborer sitting on his azz.

standard paint/stain coverage per gallon is usually figured as 400 sq/ft but with cedar shake (esp weathered) I get 150 sq/ft of stain so condition and type of substrate varies volume numbers. I know what I get on a asphalt roof but vertical cedar siding of mix Im not sure. In the past we always powerwash'd it.

I will start with an 8:1 mix with extra cling agent

-- Edited by Maverick Contracting on Wednesday 17th of September 2014 11:36:00 PM

Jeff Wible · Approved Exterior Cleaner

If it is raw blackened cedar, I wouldn't even use Sodium Hypochlorite at all. I would use Sodium Percarbonate mixed at about 1 cup per gallon of hot water then apply with a dedicated pump.

Or I'd use Sodium Hydroxide mixed at about 1 cup per gallon then DS'ed.

Or use a combination of the two.

Then neutralize with oxalic mixed at 1 cup per gallon and DS'ed,..may take a couple applications of neutralizing.

Jeff

-- Edited by Jeff Wible on Thursday 18th of September 2014 07:20:45 AM

Maverick Contracting · Approved Exterior Cleaner

Jeff normally we would but in this case just going sh route but am doing a sample with percarb. Then it's the cost factor

Doug Shaffer · Newbie

I have a small gazebo to clean. Cedar roof and the rest is untreated cedar or redwood. Where would I purchase sodium percarbonate, sodium hydroxide and oxalic acid?

waxman18324 · Founding Member Rest in Peace

Check your local chemical (SH)supplier or Univar.

Hank

Art O · Approved Exterior Cleaner

Been testing with sodium percarbonate, not liking it! But I have some new stuff coming any day. I'm hoping for better results

lkendall · Approved Exterior Cleaner

sodium percarb. requires pressure to work...

Joshua Williams · Newbie

Most of the people we meet won't even talk to us if we are using high pressure or walking on their roof at all. You are doing high pressure from a ladder?

waxman18324 · Founding Member Rest in Peace

Joshua,

I see that you're new to the NSWA. Please take the time to introduce yourself here(www.nationalsoftwashalliance.com/f602060/new-members-introductions/). You might want to re-read the thread.

Hank