Extend life of pressure treated wood

BarraOG

I have a fence and gate which are pressure treated. I read that it is ok to power wash to clean it. There is quite a lot of algae on the gate so I'll see if power washing is enough to remove this. Once I have the gate and fence cleaned, what kind of product would you recommend to protect the wood if I'm not interested in painting it. There are so many different kinds of products like oils, stains, varnishes, waxes and so on. Not sure what is effective in terms of protecting the wood and what is more about aesthetics. Thanks!

Rows Grower

https://www.boards.ie/discussion/2058310970/extend-life-of-pressure-treated-wood

You'll probably have to use a wire brush on the algae to get rid of it properly.

If you like a black fence a mixture of creosote and waste engine oil will preserve it for a long time.

Lumen

If the fence has wooden posts in the ground, IMO there's no point in treating what's above ground as it'll fail at ground level first.

The gate is different as it's presumably not in ground contact. Larsen wood preserver is what I've used, specifically Protim 265. I've heard it's not quite as potent as it used to be due to environmental regs but that would still be my first choice. Brush application, using suitable PPE.

BarraOG

https://www.boards.ie/discussion/comment/121030883#Comment_121030883

Thanks for your answer! The fence is in the form of fence panels. When the posts fail, they could be replaced without replacing the panels.

jeremyr62

Spray the green stuff with benzalkonium chloride (BAC) found in patio cleaners like Patio Magic. That will kill it. Pressure washers can damage the wood ime. I think proper creosote (the phenol containing stuff) is banned now. I also use old engine oil to preserve the wood, I just paint it on.

Lumen

https://www.boards.ie/discussion/comment/121031003#Comment_121031003

Ah right, in that case I'd just treat with algaecide/algicide and leave it. With no ground contact and no vegetation touching it, pressure treated fence panels will last almost indefinitely, in my experience. In my last house they were perfect after 12 years, but that was in Dublin where it was well sheltered.

I wouldn't spray any chemicals though, too much pollution risk.

Opinions differ though.

elacsap

If the underground part of wood posts were placed in concrete, will this help preserve them for a long time?

10-10-20

https://www.boards.ie/discussion/comment/121031201#Comment_121031201

No, the opposite as the concrete contains the moisture and they rot-out quicker!

Deregos.

I think that most of the waterbased fence treatments that I've ever used like that 'Ronseal Fence Life' are pure muck and a total waste of time and money. They're just coloured water or soluble wax dissolved in water which might look okay for a month or two but they've no real lasting water repellent or protective qualitys for exterior timber.

The original old creosote was the best stuff, but that'll soon be completely gone off the market due to VOC's and carcinogens.

There is however a new oil based product on the market 'Tanasote S40' which I'll give a try the next time I'm ever painting the shed or fences.

10-10-20

Used engine oil is problematic due to the heavy metals and carcinogens within, plus it stinks - and not in a creosote type way. Not sure I'd use it to be honest.

jeremyr62

Anything that works well tends to be problematic. Creosote, paraquat, dichloromethane paint stripper, Dichlorvos, DDT. All banned.

jack of all

I have timber gates that I made over 20 years ago that I treat with Larsen every other year. I tend to focus on the horizontal areas, end grain and corners that are inclined to trap moisture.