Presentation by Dr. Jeff Morrell, Oregon State University, on why we pressure treat wood products and important considerations in specifying and using preservative treated wood in aquatic and sensitive environments.
This was great. I wish there were more research and investment in preserving wood. There is a lot of broo-ha-ha about forest conservation and the like. A politician recently offered $20 billion towards rainforest conservation efforts. How many federal dollars are going towards maximizing the wood we already use? What about making it stronger or have other desirable properties for construction? Definitely not $20 billion.
The most readily available preservatives in California for such applications would be Copper Azole (CA-C), Ammoniacal Copper Zinc Arsenate (ACZA) or CCA.
Great video. I have noticed that some treated wood has a 2.0 rating and some has a 4.0 rating. I know that 2.0 is for non ground contact and 4.0 is for wood that will have ground contact. My question is, what makes the difference is it the amount of pressure applied during the treating process, the length of time it is left in the treatment tank or vessel, or is is it the type chemical, or is it all of the prior. I live in zone 4, so what is recommended for this area to get the longest in ground durability?
Retentions, or the amount of preservative in treated wood, are different for the specific preservative as well as the exposure. The ratings you note aren’t necessarily based on the pressure level or time in the retort. Wood treated for the same exposure, say UC4A Ground Contact, can have a different retention based on the preservative, as some are equally effective at lower levels. When choosing treat wood, rely on the Use Category to match how you will use it, not the retention.
its simple....BUY GROUND CONTACT lumber..yellowpine is all we seem to get,A BADLY TWISTING WARPING product,,,,,,,but its all they offer..this is interesting but YOU CANT TREAT YOUR OWN LUMBER!!!
The best protection is pressure treating and you cannot do that after the wood has been put in place. Finishing the wood with paints and stains can help extend the life, but that protection is not equal to pressure treating.
There have been studies of other coating products that have claimed to be as effective as pressure treating (preservedwood.org/portals/0/documents/WWPI_field_test_Hilo_Feb_2020.pdf). The results indicate such products are not effective against termites nor decay.
Today's preservatives and the pressure treating system provides much more protection from deterioration than the ways you described. The key difference is that pressure treating integrates preservatives into the wood fiber. The methods you describe are only on the surface of the wood and do not offer lasting protection.
I think there are a couple of factors in play. 1. PT pine is wet when you get it from the big box store. So Ideally, you'd want the pressure-treated wood to dry (out of sunlight!) for a week or so before installing. When the moisture levels have equalized, your wood is going to be more stable 2. Pine, the most common wood for fence panels, is a very bendy (unstable) wood.
I built a small deck with lowes pressure treated wood, the support boards, 2 x 6 's complety rooted out and fell apart? it was not on the ground. The support boards do not get stained?
Hi guys. I saw a video saying burning pressure treated wood leaves copper in ashes. That’s a health hazard. My question is can you char pressure treated post ends for ground contact (not leaving any ashes) and not have any health implications? Thanks
Charring the post ends that go into the ground will not provide much protection. It would be better to place the factory-treated end into the ground and use field treating on the cut end above the ground for best protection.
We're not aware of any research into those chemicals. Certainly, copper has proven to be an effective protection for wood. Not sure about the double diffusion process you mention. I do know that the major preservative manufacturers have sizeable research and development departments that for decades have looked into a variety of chemicals and processes to improve wood durability. The fact that those chemicals and processes are not in use would indicate they may not perform as expected.
Uh, no. Soaking wood in diesel provides little long-term protection against insects and decay fungi. There are many more preservatives available today vs. the past that are effective in protecting wood, proven by decades of use and experience.
FOR A LADY OR ANOTHER PERSON IT IS LIKE FALLING A TREE THEN CUTTING INTO SIZES 2X4 2X6'S AND THEN IF A PERSON HAD A PRESSURE COOKER LARGE ENOUGH FOR ALL OF THAT AND THE TREATMENT OF STUFF TO GO INTO IT AND THEN PRESSURE IT FOR SO LONG RIGHT ???
Not quite. You need to be registered with the EPA to purchase and use most preservatives. And you need specific equipment to complete the treating process.
Treated wood offers protection that is not needed for typical wood framing in home construction. Wood framing in a house is not readily exposed to moisture and insects, so the risk is very low. Treated wood is intended for outdoor exposures where it will be regularly exposed to water from rain and snow or when in the ground, at risk for termites and other wood destroying insects. In areas where termites are a high risk, such as Hawaii, wood framing is required to be treated under the state building codes.
Most treated wood products sold in retail locations will have an end tag that indicates the preservative used, the retention or amount of preservative in the wood and the proper application such as Above Ground or Ground Contact as described in the Use Category or UC. Not all southern yellow pine is treated, but the species is by far the most popular for pressure treating and is the most available treated product in retail locations.
@@WoodThatLasts thanks for the reply! I will be sure to look today. Looking to replace my boat trailer bunks, but it’s aluminum and wouldn’t want to have any copper treated wood around them. But this was the first video (and reply) that broke it down more simple, thank you🫡
Preserved wood is a good choice for garden boxes. Research by Oregon State University (preservedwood.org/portals/0/documents/PW_in_planters.pdf) shows any preservatives migrating from the wood do not impact the vegetables or plants. You'll want to make sure to specify a Ground Contact treated wood, since garden boxes contain soil that will hold moisture near the wood and increase the risk of deterioration.
@@northernspur6282 the copper additives of store bought stuff has it’s advantages for stopping bacterial growth. If you add some store bought stuff to used motor oil, you have the best of the best. Additionally, the store-bought stuff has drying agents in it. I have made this mix before and I can tell you from years of firsthand experience this mixture is the best of the best and when you wipe it off after you’ve coated it it dries just like linseed oil. Best stuff ever.
Dipping wood in motor oil simply does not work to protect wood from insects and decay. Using motor oil only makes the wood more flammable and the odor makes it impractical to use.
AWPA standards for borate to meet Use Category 1 and 2, above ground for interior construction, require retention of 0.17 pounds per cubic foot (pcf) for areas without Formosan termites and 0.28 pcf for areas with Formosan termites (typically coastal areas of Southern California, Texas and the Gulf States). Please note these standards are for pressure treating, which can only be done in a manufacturing setting. Just brushing or rolling on a borate-based coating will not provide the same level of protection. Also note that borates are only intended for interior use where the treated product will not be exposed to liquid water. Borate is water soluable and its protective qualities will be diminished with exposure to water.
Neither of those methods simply do not work to protect wood from insects and decay. Using motor oil only makes the wood more flammable and the odor makes it impractical to use.
The quality of today's wood is so inferior to that of 50 or 100 years ago that a preservative is necessary to get to last a fraction of what yesteryear's untreated wood would last. That has been my experience.
That is simply incorrect. Trees and the wood that comes from them have not changed over the past century. Wood from the past deteriorated just like the wood of today deteriorates when unprotected from insects and decay fungi. Preservatives in wood are necessary when that wood is used in applications where there is high risk to deterioration. That has always been the case and wistful thinking that everything was better in the past is erroneous.
I agree with the OP. Treated wood warps, it's full of cracks and stripped areas, it's not dense, and the wood type is never labeled. That is relatively new in the market. I never saw such crappy wood in the 60s and 70s.
