EFC-38 - Use on pine shed

[acsipresident]

Hello, I have a 16x12 shed with a pine lap board exterior. The shed has no finish on it and has been weathered for 3-4 years. I used EFC-38 at 8oz per gallon and it didn't seem to cut through the mold that has built up. Actually, that green portions of the wood didn't seem to be affected at all. Is there something different I should use or do you approach a pine exterior differently? I recoated the surface and gave it a REAL good scrubbing and you could see the buildup on the brush but it seems to me this stuff should have cut right through it. Is HD-80 necessary for this.

Your help and experience is truly appreciated.... Paul

 

[CaroliProWash]

I was on the phone with Russell today and I mentioned your situation. He said that sometimes if the build up of mold and mildew is really heavy it can take more than one application to remove. The build up prevents the material from getting into the wood at the root of the problem. He said to extend your dwell time or treat it a second time.

You can take a number of approaches to a severe build up of mold or mildew. One approach is to plan for two applications of product. Another as you mentioned is to scrub the surface to help the product penetrate through the build up. You can also pretreat the heavily built up surfaces with bleach to aggressively attack the build up and then rinse. After that you can continue to treat the job like any other wash.

A product like HD-80 is very aggressive and will work well on a heavy build up, but it is not as safe for the wood as using EFC-38. In some cases it is actually better for the wood if you treat the build up with bleach first and then clean the wood with a safer cleaner like EFC-38. It is really up to you and the results you are looking for. Sometimes to treat the wood with the most gentle solution will require longer dwell time or a second application. We always try to use the least aggressive approach that will deliver the quality result you are looking for.

Also, remember NEVER to mix EFC-38 with bleach. Always rinse between applications. Also, bleach works quickly and is fairly easy to over apply. If you do use bleach you should plan to brighten after you wash to help return more of a natural appearance to the wood.

We take the preservation side of the business very seriously. If you do more damage to the wood while getting it ready for staining you are actually working backwards.


Celeste

 

[acsipresident]

The buildup was significant and found that after a good scrub and second treatment the surface cleanup up nicely. Without that semi-stiff brush this mold and mildrew was going nowhere.

The bleaching is a good idea and one I'll need to try. In New England we see a good amount of this and working through an approach that isn't as time consuming will improve profitability and save the money I'd spend on ibuprophen.

Thanks Celeste

 

[acsipresident]

Okay, I thought I'd offer an experience I had cleaning my pine shed . This shed is 3-4 years old and had no sealer applied. Because this is my own, I was able to try a few things in different areas to determine the results.

First, I applied EFC-38 on the front of the shed using the recommended 8oz per gallon. Using a hand pump sprayer, I gave the front a good coating and allowed to dwell for 15-20 minutes. Any longer and it would have dried. After rinsing thoroughly I allowed the shed to dry. Sad to say there wasn't a significant change. I applied a second coat and contributed some muscle and a scrub brush. Yes, it did look better but no much. I was very disappointed.

Second, I decided to give the EFC-38 another try on another side of the shed by increasing the mix to 12 oz per gallon and following the same process. Again, I was disappointed. The grey remained, maybe a little lighter in some small areas on each board but nevertheless it was still grey with all of the (mold, mildew, algae) along the bottom two feet of the wood.

Third, I decided to apply a bleach mixture (50/50) of household bleach to water. As soon as the bleach hit the wood the color came up and the mold began to disappear. I allowed the bleach to stand for 10 minutes before rinsing and rinsing and rinsing away. Now the entire shed looks super.

So, what is it that I should take away from this? I expected EFC-38 to deal with faded, grey wood and it didn't. I expected this product to cut through any mold, mildew..etc but it didn't. Even my test area (small) using HD80 didn't eliminate the greying and instead made it darker. That stumped me. Using an inexpensive solution of 50/50 bleach solved the problem.

Okay then, when do I use EFC-38? Why didn't it work on a pine shed that was grey and molded from four years of sun and shade exposure? I don't have confidence in doing a customer's deck with this product having gone through this experience.

I could really use the wisdom of those folks beating the drum for this product and it's sister product HD-80. Where did I go wrong... or did I? I am truly looking forward to the feedback and lessons this forum can supply.

Paul

 

[PressurePros]

I get good results on wood decks with EFC-38. However, when there is a buildup of mold, your dwell time has to be longer. I think your inexperience with both wood restoration and the EFC are partly to blame. You need to keep your wood wet with chemical. I don't have the answer as to whether or not bleach is a viable solution in wood restoration. My instincts still say it is not. I think bleach masks some problems and people confuse that masking with clean wood.

On the other side of the coin, there are some guys out there producing decent work using bleach. You have to decide which is better for your business and go with it.

 

[Jon Fife]

ACSI,

....I think it depends on what your definition of "rinse" is. Lots of manufacturers say to rinse, etc., but what that essentially means is to "pressure wash". Meaning, you have to get the tip up there with some pressure, to remove the grey wood.

 

[acsipresident]

I must agree that I am inexperienced with the cleaning process and chemicals and certainly have done my best to exercise the advice of those contributors to this board. As for the results I saw with EFC-38, they were the product of multiple applications, allowing each to dwell no less than 15 minutes while insuring that none had dried along with the use of a pressure washer. I was careful enough not to get too close but close enough to exert strong pressure. From past experience, getting too close to pine siding causes significant damage.