Treated timber
Welcome! / Forums / General Woodworking Discussions / Wood and Wood Preparation / Treated timber
- This topic has 12 replies, 8 voices, and was last updated 11 years, 1 month ago by Scott.
-
AuthorPosts
-
3 September 2013 at 7:06 pm #17410
Hi all I’m very close to starting my first project when my bench is finished. I’ve been thinking what I should try but the boss (wife) has decided for me, she wants some planters and seating for our terrace. As it will be my first project and mistakes will inevitably be made I don’t want to use expensive hardwoods. Has anybody used pressure treated timber like we have in our garden centres here in the UK for fencing etc. I don’t know if using it would have a detrimental effect on my newly acquired tools. Any suggestions would be very much appreciated.
3 September 2013 at 9:48 pm #17416I have done quite a few decking jobs in my time with steps balustrades etc . Treated timber very stringy bit wet hard to explain not the nicest of stuff to use.
Remember to treat all cuts made.
Wipe tools off as treated timber can have erosive effect.
I would also use a hard point hand saw more suited to that kind of timber.Pat-
You might want to try a rot-resistant species of wood and leave the treated lumber for construction projects. I know the treated lumber that they have here in the US should never be used for anything (like furniture) that comes in frequent contact with skin. Nasty chemicals.
Here we have California Redwood which fares well (planters, picnic tables, benches, probably too soft for finer furniture), but I’ve read that cedar, cypress, and white oak do OK as well.
I am not familiar with the UK/European woods, so you probably have to poke around.
4 September 2013 at 2:20 am #17438Hey Pat
I am in agreement with Mark and Scott here. I do a lot of outdoor furniture here in the US, and I never use Pressure Treated Lumber. I just don’t like the stuff for areas where there is going to be human contact, for all the reasons listed above. The links that Ken listed give some good information about the hazards associated, well worth reading. Thanks Ken for providing those.
So, what do you use in England without spending a lot of money? I have no clue, if you were here in the US, Western Red Cedar, and Cypress will give you the best bang for your buck. If you have any local businesses that build decks, see what they use, that will be a good source of information to start with.
Keep us informed of what you find out and post some pictuers of your projects!
5 September 2013 at 11:50 am #18058Thanks for all the help guys, I hadn’t considered the chemicals and contact with people. I’ll probably go with pine and try to protect myself, maybe paint them.
5 September 2013 at 12:37 pm #18061Western Red Cedar is available in UK very good for out door use. Dose take finishes and stains well.
Also quite resilient without finish but colour will change from red brown colour to a silver grey.5 September 2013 at 4:46 pm #18064As already mentioned, avoid using pressure treated timber – it’s mainly used for bearers and suchlike where it won’t come into contact with skin.
For external projects, you can use whatever timber you like as long as you treat it properly. You can use pine, spruce, fir or whatever as long as you apply plenty of treatment to stop rot and insect attack. Not all timber needs this treatment though – for example, the extractives in oak are toxic to most insects and takes forever to rot so there’s less need to use that sort of treatment. However, if you want to stop the timber from greying out you’ll also need another treatment to block UV rays, or you’ll have some nasty washed out grey timber. Unless you like that look.
I looked at treatments for external timber a lot when building my shop. The biggest shock to me was the price of the stuff.
Hope this helps.
George.
6 September 2013 at 7:43 am #18133Pressure treated timber aint wot it used to be apparently. I was talking to the warden at a fen nature reserve a few weeks ago. They had put in some “tanalised” gate posts, and after only 6 or 7 years they are rotting out and need replacing. The “eu” has changed the rules and the chemicals used are weaker or something. You only need to cut open a post or joist to see that the treated section only penetrates about 1/2 ” or so. I have seen posts that look like they have been slashed by a machine, presumably to aid penetration of preservative-but then surely isnt that also going to encourage water to get in faster? I dont think its even pressure treated any more like in the old creosote days. Look how long railway sleepers lasted. LOL my grandad built a rose arbour in about 1925, he used teak posts and beams. When the house was sold after he died in 1989, those posts were still good…
Sweet chestnut is good for weather and rot resistance, the tannin in it being a natural preservative. Just makes your tools look like someone used a black felt tip marker on them…(no idea if that would affect plants grown in a chestnut container though…). Western red cedar as mentioned already, light easy to work with and rot resistant. Douglas fir might also be a good bet
Personally I would probably use oak for outdoor seating-but wouldnt do it as a first project.
hope it works out whatever you decide on6 September 2013 at 8:50 am #18135I suppose on a practical level you should consider whether first off you want a natural unfinished finish or another way of actually applying finish. If as you say it’s sitting on a terrace and not dug into the ground then you could consider finishing the wood with a proprietary finish. Many waterborne finishes have proven good. I made a bench three years ago from B&Q scant, the cheapest wood I could find. I left it to surface-dry thoroughly for a week and then worked with it to laminate parts and form joints. I then painted three coats of Ronseal water-based varnish (rosewood) and it’s doing fine outside all weathers.
6 September 2013 at 11:00 am #18137Thanks for all the advice chaps. I’m beginning realise now how complicated wood is. I think I’ll go with the cheap option as Paul has suggested for a first attempt and the graduate onto the more expensive woods if it turns out successful.
[quote quote=18133]Pressure treated timber aint wot it used to be apparently. I was talking to the warden at a fen nature reserve a few weeks ago. They had put in some “tanalised” gate posts, and after only 6 or 7 years they are rotting out and need replacing. The “eu” has changed the rules and the chemicals used are weaker or something. You only need to cut open a post or joist to see that the treated section only penetrates about 1/2 ” or so.[/quote]
I had the opportunity to obtain some large wood utility poles that were being removed in a light-industrial area. They were about 16-18″ in diameter, each section already cut to 6′ long. You always hear how the trees for these poles are carefully selected for their straight grain and overall grade. I was very tempted, but the foreman on the job told me that they were pressure treated all the way through to the core. No thanks…
-
AuthorPosts
- You must be logged in to reply to this topic.