Wood preservatives.

I recently constructed a new pergola using pressure treated timber and I then painted it using Ronseal Fence Life Plus which I have used for many years, but it now seems thinner than it used to be and it started washing off after 3 months. On checking the review sites I find most users now give it 1 star. I considered Cuprinol Ducksback but users are also giving this 1 star. I bought Ronseal Trade 10 Year Woodstain which is 8 times the price of Fence Life at £40 for 2.5 litres, but this seems no better. I am now considering Sadolin Classic at the same price, but before wasting more money I thought I would turn to this forum for advice.
Can anyone recommend a wood stain/paint/preservative that has good coverage and lasts a few years? When the rambling roses have grown over the pergola, it will be difficult/impossible to recoat the timber.

 

I don't think there are many preservatives on the market these days it's all mostly decorative.

Sadolin used to be good, but if that has also gone down the water based/environmentally friendly route you might as well not bother.

 

I'd be inclined to use something like teak, danish or linseed oils. Anything water based is a waste of time and money for outdoor stuff.

 

Sadolin Classic is still oil based which is why it's on my list to try next unless anyone on here can suggest otherwise.

 

I believe all of the oils you mention require at least annual recoats which is not possible on a rose covered pergola. They are only good for furniture.

 

You can use anything really but most will need reapplying.
There is no such thing as a "one off" treatment other than the pressure treatment the wood has already had.
Oil based treatments are better, but will not last more than a few years before needing a new application.

 

Re applying every other year or third year before the buds break surely must be better than the greying effect of outdoor wooden structures?
Never used it myself, but tung oil is meant to be ok for pergolas with plants growing over them

 

It's almost impossible to paint timber that is covered in climbing roses. The timber itself should be good for many years as it is tanalised but the brown colour is what needs to last as long as possible. I have a bare structure atm so now is the time to paint it before the roses start their climbing. As I said, Ronseal used to be good and it is everywhere in my garden on arches and arbours but it is thinner now than it used to be. I need to keep things looking as good as possible because we are with the National Garden Scheme and we have the public paying to visit the garden.

 

I actually don't mind the appearance of weathered timber, but I suppose it depends on the setting that it is in.

Surely nothing is going to look perfect for more than a couple of years before it needs recoating .

 

That's what I'm trying to determine. Sadolin Classic claim 10 years but it is a satin finish which is not ideal for a pergola.

 

Have a look at this:
www.thepaintshed.com/zinsser-allcoat-exterior-satin-sb-colours?gclid=EAIaIQobChMImMC3k424_gIV0tLtCh0S5wWMEAQYAyABEgJvh_D_BwE

 

That was the other one that I could not remember the name. It is the same satin finish as the Sadolin Classic which I am not certain about. I tried a satin before and it tends to reflect the light from the sky which detracts from the colour of the roses. Matt is much better but Sadolin and Zinsser only do satin, probably because they are really designed for windows and door frames.

 

Just had a look at that. Never seen it before. Not sure if it will besuitable for a pergola. All the reviews I read were for fances and sheds which are always quite rough wood, whereas the timber I used is fairly smooth, which could be some of the problem I am finding. However, it is cheap so I may give it a test. Thank you.

 

I was going to suggest Cuprinol ‘Garden Shades’ range, it’s always lasted pretty well. Not so good on smooth surfaces though.