Oak window

[borischarlton]

Hi

I am just wanting to check I have done the right thing. I have had made a beautiful oak window that I have installed as a replacement on the back face of my cottage. I just want it to age and go silver and definitely not to paint so I have not put any coating at all on the outside. My farther in law who helped me put the window in is adamant that if I do not put oil/wax/some sort of coating on it, it will stain black. I am sure that I am correct but would like some reassurance.

Many Thanks

Rob

 

[Feltwell]

Biff Vernon is your man for the expert opinion - but as far as I'm aware, leaving it strictly alone is the way to let it go grey, and it won't go black (in fact I seem to remember that certain oils can actually cause problems and make it go black). You shouldn't use any steel or iron fixings either, as they can cause staining.

 

[Flyfisher]

I agree with all that. I was looking around timber yards for oak last year and none of it was blackened by being stacked outside, just a nice silver/grey.

 

[MdB]

From Biff's Website

http://www.biffvernon.freeserve.co.uk/oaks_and_ends.htm

In Tudor houses, where wealth allowed, quite extensive area came to be glazed. Large stone-mullioned windows in brick and stone houses and casements that occupied the whole space between vertical timbers in framed houses became quite an architectural feature. Craftsmen seemed to get quite carried away at times with the ornamentation of wrought hinges, sash fasteners and stays. Where timber was used oak was the material of choice. It was left unpainted, allowed to weather to a silvery grey gradually darkening over the years. Its strength and durability is proved by the survival of 500 year old window frames, still in serviceable condition.

http://www.biffvernon.freeserve.co.uk/intro.htm

My windows are a bit unusual. I use oak because it is very durable and very strong and looks nice. The durability means that it does not need to be painted or treated with poisonous chemicals. Many people are surprised at this. There is a common view that any wood that is not painted and/or treated with preservative will rapidly rot. Reality is not so simple. Wood only rots if it is wet. Most parts of a window stay pretty dry most of the time. They get wet in the rain but because they are left hanging up on walls they dry out when it stops raining. That said, the sill and lower rails can stay damp enough for rot in some situations. Many softwood timbers that have grown quickly soak up and retain the moisture and provide a good home for moulds. They need to be protected from the wet so keep them indoors - not so much use for windows. Slow-grown pine is not too easy to come by; the quality found in the softwoods commonly used in the 18th and 19th century is rarely seen. Some softwoods, particularly larch and Douglas fir, are naturally very resistant to fungi, and can be used in exposed situations with little fear of rotting so long as they get the chance to dry out from time to time. Oak is even more durable than larch and Douglas fir. It can be used in external joinery, exposed to the weather, and will last for hundreds of years. Take a look at a timber-framed Tudor building. Four centuries of rain and sun and the oak is as tough as ever.

So why not paint the wood like most folk do? Most folk have found their wooden painted windows are rotting and so they replace them with nice, bright, white 'low-maintenance' uPVC windows. What's going wrong? Most paint used in the last fifty years for exterior joinery has been known as 'oil paint' but should perhaps be called alkyd paints. They are very waterproof, keeping the wood nice and dry. Until they crack, that is. And sooner or later (probably sooner than you expect) cracks in the paint layer do occur and then water can get in. The paint forms an effective waterproof layer to stop the moisture getting out again so the wood can't dry out. It stays wet - nice for the moulds. After a while water trapped below the paint lifts the paint right off the wood and it flakes. Eventually and too late you get round to repainting it, or more likely, give up in despair and call in the plastic window man. In the good old days paint was made of linseed oil. This was breathable paint, behaving rather like a Goretex jacket, it shed the rain while allowing any moisture in the wood to evaporate out through the paint layer. The wood stayed dry and didn't go mouldy. More about paint on the Paint page. Technology...bah!

Oak neatly sidesteps the problem of rot because because it's naturally full of chemicals such as tannins which just ain't good for fungi. So my windows look unusual from the outside. They are not painted but left as bare wood. Oak weathers in the sun and rain to a silvery-grey colour with a rough open texture, but this is only skin deep. Below, the wood stays strong and gets harder as the years go by, No painting. No maintenance. Not in your lifetime, not in your grandchildren's lifetime. The plastic merchants don't dare claim that. OK, there are situations where exterior painting is appropriate. A terraced house in a conservation area with every other window in the street painted white. There's no question. But I use linseed oil paint and coloured not the 'brilliant white' that was only introduced in the 1950s.

 

[Penners]

My farther in law who helped me put the window in is adamant that if I do not put oil/wax/some sort of coating on it, it will stain black

Apologies to your farther in law (and the nearer one, too, if necessary) but that's rubbish.

Left without a surface coating, the oak will weather down to a silver grey colour. It will only go black around any ferrous metal that's been driven into/placed against it. And don't worry about the oak's longevity in this situation, either. It'll see you out!

 

[MdB]

Gypsum (or something in the pink stuff) makes oak go black very quickly as I have found to my cost..

 

[borischarlton]

Thanks for your replies. I am sure you can see the situation, he helped and does not want to see an eyesore and I must admit it is looking a little sorry at the moment. However I am now happy it will silver down nicely.

Rob

 

[Flyfisher]

Sounds like you'll have to put up with "I told you so" comments for a little while before nature takes it's course and you'll be able to have the last laugh.

Just don't let anyone sneak in while you're out and "help out" by applying anything to the oak!

 

[biffvernon]

Yes, new oak becomes a real mess on the building site. Lime can have some spectacular effects; purple can be a surprise. But it all fades away and in a year the timber will look just what it ought to. Do nothing and let nature take its course.