wax or spirit based preservative for new shed

[Bill]

hi

Was wondering if anyone has any experience of both types of wood preservative?

Five years ago, I painted my new untreated redwood shed with Cuprinol Ducksback wax based wood preservative.

As the years rolled by, I noticed I still needed to re-apply the preservative each year despite the product's claims.

But more worrying was the shiplapped wood suffered from quite a lot of shrinkage causing the knots to dry out and drop out, and large gaps appearing between the boards, especially on the walls exposed directly to the sun. This got progressively worse as each summer came & went.

Now, it's possible may be the redwood used in the construction of the shed had far too high a moisture content as it was errected in late November if I recall and it was a very very wet month for that year.

But I also wonder whether the wax based preservative is contributing to the wood shrinkage problem too over the years?

I've since moved and just had a new tanalised shed installed.

When I looked in B&Q today, I now notice all Cuprinol and Ronseal wood preservatives for sheds/fences are now all wax based, but I did manage to find a small display of spirit based preservatives from those two companies.

I'm thinking of using spirit based wood preservative this time round.

Was I just unlucky with my previous shed, or is there something I'm not aware of about these new wax based wood preservatives?

bill

SE England.

[Andy Hall]

I've seen similar effects with these products.

I think that that's a very good idea. I always do the same. I have found the water based waxy products not only to be ineffective but also to leave a finish like a child's paintbox. Basically, they completely spoil the appearance of the wood as well as being pretty useless at the job that they are supposed to do.

If you are looking for more choice and better products that are solvent based, then take a look at Sadolin's range. They also have some entry level water based products for garden use, but also have their Classic range of preservatives which are much more substantial and do more than they say on the tin rather than less. Sikkens has a similar range.

If you want more of a colour choice, then take a look at Jotun products. These originate from Norway and essntially you can have whatever colour you like. Their quality is better than the others but pricing is around £10 per litre.

[Chris Bacon]

Shouldn't need much treatment. Why can't you se creosote (substitute)?

[Steven Briggs]

In message , Bill writes

[Snip]

I have much more faith in the sprit based stuff, and it seems to penetrate the timber better than the water/wax emulsion stuff. The more dire warnings on the side of the tin the better in my mind. Try a trade type place (Builders merchant or timber yard). I've used the Blackfriar stuff quite a lot. Screwfix 86050 and similar, although I pay about £11 per 5ltr at a local place. You may well need a good organic vapour mask if using this stuff more than 1/2 hour or so. It certainly stinks while drying, and makes me feel pretty rough for a day two if I get a good lung full. Screwfix mask 14194 is extremely good, I can't smell this preservative at all through one on these, and suffer no ill affects afterwards.

[meow2222]

Best stuff I've found is a 50/50 mix of engine oil and either paraffin or diesel. New oil for clear, or controversially, used oil for dark. Used this on a softwood construction used to hold damp soil, and the wood was still perfect years later.

NT

[Stuart Noble]

If you don't mind the tacky, dirt attracting surface you get with non-drying oils, you might as well use vaseline, which is 100% hydrophobic and solvent free, without the drawbacks of emulsions.

[Pete C]

This is a VERY bad idea IMO as the detergents in engine oil will guarantee that carcinogens in used oil will leach out into the soil. Someone may be growing veggies in that soil in years to come.

I'm not sure that new oil on it's own would stop rot either, unless the wood was completely soaked in it.

Cuprinol Green or similar is good for this as the copper in it locks onto the wood quite nicely and isn't too toxic, google for copper napthanate for more info.

cheers, Pete.

[meow2222]

It soaks in, it doesnt create a mess. Vaseline would not work at all well. Once again, understanding how it works would be a good start.

Pete C wrote:

It already did.

NT