KD HT lumber vs PT lumber for deck

[Bruce A. King]

I am finding lots of info about how HT (heat treated lumber) is required for packaging, pallets etc to prevent the spread of some WDO across the world but can not find anything concrete on whether or not it is suitable for a deck.

I did find a post about how the PT label might be cut off the end of a board and the stamp that is left shows HT or kiln dried HT.

Most of this new treated lumber looks untreated as compared to the old green stuff, I did learn that they add color to some of it to try and make it look more like treated. The label will show w/CE which means "with color enhancement".

Any lumber experts out there that can confirm KD HT is ok for a new deck?

[Mark S. Tyson]

it would be unsuitable unless it is a naturally resistant wood such as teak or redwood

[Bruce A. King]

I did some research and found that they only staple the PT label to the end of the boards in many cases. It could be HT and then PT'd later?

I have to call this lady back again at COX lumber, I had called her about something else and she was very knowledgable. She said that some of the new PT looks so much like untreated they have to add a color enhancer to it. The stapled on label will have w/CE to indicate "with color enhancement"

[Mark S. Tyson]

she is correct. it is damn difficult to tell the differance on the new stuff. check out this FAQ web site. it also has several good links.
www.strongtie.com/products/ptwoodfaqs.html

[Bruce A. King]

Here is the most recent link

http://www.strongtie.com/productuse/PTWoodFAQs.html

[David E. Helm]

Don't know anything about the HT lumber, but if you are in the west, the PT is still Western Hemlock and looks pretty much the same as before. Don't know how PT Pine looks. I guess it is just a regional thing.

[Marcel R. Cyr]

Bruce, I found more info on the heat treated wood.

It appears as a new technology from Canada.

I grabbed an exerpt here and there and put it all together, for I was on a lot of different sites and suppliers.

Heat Treated Lumber

WWPA offers a heat treatment certification program for mills to stamp qualifying lumber with the KD - HT mark.
This service is intended to assist mills in supplying products that meet the standards for wood packaging
materials that may be exported.
Wood Packaging Material (WPM)

Wood packaging material made of unprocessed raw wood is recognized as a pathway for the introduction and spread of pests. To limit the entry and spread of quarantine pest through international trade, the International Plant Protection Convention adopted the International Standards for Phytosanitary Measures Guidelines for Regulating Wood Packaging Material in International Trade (ISPM 15).

Termawood is an unique technology that uses heat treatment for timber processing to significantly improve various characteristics of wood.
Termawood vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C without ANY chemical additives.

The molecular changes in wood composition result in unique features:
• Water-repelling at a molecular level
• Dimension stability improves 12-17 times compared to untreated wood
• Resistance to biological decay is 15-25 times higher then of untreated wood
WestWood Heat Treated Lumber Production Corporation is unique technology that uses heat treatment instead of chemicals for timber processing to significantly improve various characteristics of wood. WestWood Heat Treated Lumber Production Corporation vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C (450 F) and exclusive of any chemical additives. The molecular changes in wood composition have a result of dimensional stabilization, protection against rot and wither, and as a result, expanded use opportunities.

Hope this helps a bit.

[Bruce A. King]

Thanks guy's!

The stamps on lumber do not always include everything, the PT data is usually just on one of those plastic tags stapled on the end of the board which gets cut off or removed. So if you see HT on the stamp there's no real reason to doubt its treated.... but there is no way to know for sure on a brand new deck.


Here is another good link a guy posted over on Ins News
http://www.anthonyforest.com/pdfs/AW...stem-U1-07.pdf