The homeowner has requested some assistance getting his cedar cleaned.
The cedar is 4 years old and the cedar needs resealed.
The pictures are what his siding looks like now, and you will see he started to just pressure wash the siding. He definitely is removing a layer of wood when he pressure washed with just water.
We did a test area with a light SH mix, Agent Blue and followed with a coat of Wood Restore.
The issues I see are:
1. The dark small black spots that must be a form of organic growth. (The test area lightened but did not remove them completely while on was onsite. I have not been able to confirm how it looks now that it has had a couple days to dry)
2. How best to clean this cedar to leave it ready for a new stain. (His concern is will a neutralizing step with oxalic or Wood Restore hamper his sealer from adhering?)
3. Best Stain for the customer to use-- Seems like Armstrong Clark is highly regarded by our wood experts on the forum
4. Why are there growing black circles around the staples in the lap siding bottoms? My thinking is those became penetration points and water is causing the "molds" to grow, and the staple is going to rust
5. Is it typical to dry out that quickly? The homeowner prior to installing the siding sealed it on the front and back.
6. Is it typical to staple the bottom exposed edge of cedar siding? Wouldn't that cause it to cup as the wood tries to move?
The last image shows the protected siding under the back porch by the electric service box
Hoover has a great recipe. Sodium per carbonate with caustic soda, rinsed with oxalic. The black at the staples are most likely rust. If you don't secure the bottom it will curl fast. Here are pictures of a home we did a few years ago. The first two are before, after cleaning then after stain. The third is B & A.
(His concern is will a neutralizing step with oxalic or Wood Restore hamper his sealer from adhering?)
Quite the opposite. The PH needs to be lowered back down so the stain will adhere and last longer. Oxalic acid. Plus it will remove bleeding from nails or staples. It also brightens Cedar & Redwood after stripping. Especially Redwood. Redwood gets real dark when stripped. Within 5 seconds you see it brighten like magic!