How to choose the correct Treated Pine H Rating for your project.
I needed to purchase some treated pine for 2 different projects. One was for some internal framing, which I wanted to protect against termites, and the other was for a gate post which would be outside and in the ground.
After talking with my local timber merchant I found I needed “H2 treated pine” for the internal and “H4 treated pine” for the outside gate post.
An explanation of the Treated Pine – “H” rating.
The “H” stands for “Hazard” and there are 6 main levels of Hazard Treatment in treated Pine.
UPDATE: The additional of Hazard Levels H2F, H2S and H3A have been sourced from the Timber.net.au Australian Timber Database.
Here is a simplified list of the different “H” ratings and their applications:
- H1 Treated Pine : To be used indoors, above the ground. Not resistant to termites.
- H2 Treated Pine : To be used indoors, above the ground. Resistant to termites.
- *H2F : Same as H2. You see this in the Blue Construction Pine.
- *H2S : Same as H2. You see this in LVL/Plywood.
- H3 Treated Pine : To be used outside, above the ground. Resistant to termites.
- H4 Treated Pine : To be used outdoors, in ground or ground contact. Resistant to termites.
- *H3A : Same as H3. Used in Facia boards, doors etc that are maintained with regular painting.
- H5 Treated Pine : To be used outdoors, in ground with water contact. Resistant to termites.
- H6 Treated Pine : To be used when in constant contact with salt water.
Hope this clears things up a bit when deciding on the treated pine you need for your next DIY project. Make sure to ask your timber merchant for a more in depth description and application for each type.
Thanks for the info to this information challenged person. This has helped me get the right timber for the job.
Steve, I have a ozito table saw and having troubles with alignment. I read on the ozito site that there will be a kickout when locking down the guide rail.i find this strange. What happens when I attach a sled. I was using an aldi with success until motor gave out. Was very happy with cutting. Reluctant to make sled to fit ozito until I rectify a possible problem. Ozito take the view that it acceptable as is.
Hi Bob,
The locking down the guide rail thing does seem a bit strange. Can you send me the link to where you read that.
I’d also love to see the kind of sled you use on these DIY saw tables.
G’day Steve,
I work in a timber yard and have just had a customer tell me that he needs H5 treated pine stumps for a deck he is building, this si the first I have heard of stumps needing to be H5 rated, just wondering if you have any info that could clear this up.
Cheers
Hi Tim,
H5 is only needed if the timber is in constant contact with water. The specific conditions state:
“Subject to extreme wetting and leaching where you require a higher degree of protection”
Click the link at the end of the above article for more Technical Information.
Cheers
Steve
Hi Steve
How can you distinguish between H3, H4 & H5 timbers?
Frank
Hi Frank,
As far as I know you, you need a stamp or something telling you the difference.
Most sleepers and round posts are H4 though.
In structural timber you can tell H2 by the blue colour,
and the difference between Radiata and H3 you can tell by the smell of a freshly cut end.
Hope this helps. If you find any other info on this please let me know.
Cheers
Steve
Thanks for the reply Steve, but I’m looking at timber in the ground that should have been H4 or H5 — and I think that H2 or H3 was used, because it is now badly decomposed due to to extreme dry-rot .
Frank
Sorry again but unless there is a stamp on the end of the timber there really is no way of telling. Most landscaping timbers (sleepers and posts) should be H4. It sounds like yours must be H3.
Hope it’s not too hard to replace.
Steve
hey mate how long did it take for it to rott
Hi Steve
I want to build a 6mtr x 4mtr deck in a town house court yard, with no access other than thru the living area then 5 steps down into a hall way.
The builder had paved this area however too basic, have removed the pavers and most of the packing sand.
Height from living room floor to outside sand is 160mm.
I cannot build using stump/bearer joist method and propose to build just using bearers 140mm x 45mm structural treated pine 450mm spacings laying direct on the ground, if i need to i can place a post if required and fasten to side of beam,deck will be composite eco deck.
Drainage is quite good as we are pretty much on sand.
I also intend to paint the beam as extra protection.
What other tips could you offer
Thanks
Gary
Hi Gary,
It’s tough to comment on a project like this without seeing the site. The only thing I would consider is putting in a few short posts/piers. Dig down to a solid foundation and concrete them in. Then bolt your bearers to the posts. This should help to avoid any movement and sinking into the ground.
Also, make sure all timber is treated H4, not H3.
Good luck!
Steve
Thanks Steve
Would you paint the beams for extra protection
I think the paint would be a waste of time and just break down quite quickly sitting on the ground. You should probably ask a paint supplier for the best answer.
Hey Steve,
I bought H4 treated pine and have used it indoors to make a shelf support. It really smells however it has only been there for a week. Should I remove it and replace it, or can seal it with something, or can I even leave it alone and wait for the smell to go?
I should have researched first before I got stuck in.
Cheers,
Shaun.
Hey Shaun, if it’s not too much trouble I would just replace it. If it was H2 you could probably just paint it, but H4 I’d want out of my home.
Cheers
Steve
Thanks Steve
Hi Steve my builder has put h3 treated timber pine as framing to raise my lounge room floor. It’s been two week and the whole house now has a strong smell like turps. The frame h3 has 19mm chip board on top of it and under neath. Should I remove it from my house or will the smell go away. The smell is making me sick.
Jules
Hi Julie,
It’s strange that H3 was used inside the house. It’s normally only used outside where the timber will be exposed to the elements. It’s also strange that with the 19mm Yellow Tongue Flooring that the smell is getting into the room, and that the smell is that strong. I would definitely call the builder and ask him to have a look.
With the turps smell, did you have any varnishing or oil based painting done recently?
That’s all I can suggest. Sorry I can’t be of more help.
Steve
Steve,
Thanks for getting back to me.
The H3 treated timber pine smelt way bad before it went into the house. I told the builder it stank and he said it was just residue and would dry and the smell would go, well no it been 2 weeks and i cant use the top floor of my house due to the smell. it giving me head aches. The builder said the timber will dry eventually. Do you know if there is any law againts using H3 timber inside a residence.
.
and nope no painting or varnishing has been done.
Hi Julie, I don’t know of any law, and I don’t understand why the timber needs to dry.
I would contact your council for and get a building inspector to have a look, or find another builder to give you a second opinion. Even if you have to pay it will be worth it.
Sorry I can’t help more.
Take care.
Steve