Oil/varnish or none for external oak door

[jfb]

So I have two solid oak doors (external) that are going in.

 

Would it be crazy not to put any oil or varnish on them? I am happy for the colour to age naturally.

I have 2 carpenters on site and one says go with Osmo/Danish oil and the other says don't bother.

Doors are on sheltered side of building not in a wet area.

 

The only argument I can see for going with some sort of finish is that it can cut down on any expansion/contraction but I'm not sure how much that is true.

 

[PeterW]

I would be using a microporous varnish on them as they won’t just age they will discolour and potentially warp if they get wet. 

[tonyshouse]

I would use nothing, or boiled linseed oil or waxoil 

[Temp]

We have a lot of exterior oak and in my experience...

 

a) If you want it to go silver after 5 years of black, blotchy and perhaps even slimy then do nothing. I let a field gate do this.

 

b) If you want to maintain a honey colour with low maintenance then something like 1 coat of Sadolins classic and 3 of Sadolin Extra clear brushed on very thin. I mean thin or it will look like treakle. Thin and it looks great. Our front door has this.

 

c) If you don't mind some maintenance... 1 coat of Danish and 3 of Osmo UV Phrotection Oil. Put a new coat of Osmo on every 3 years. We have lots of external oak beams with this.

 

d) If you actually like maintenance and dont mind the oak going darker brown...then go for Danish oil on its own. However you may need to recoat it every year, perhaps even twice a year if very exposed or it will go black and blotchy on its way to a). Our external beams started with this then I sanded it all off a few years later to switch to c).

 

Try your choice on some scrap oak first.

Edited September 4, 2020 by Temp

[Redoctober]

Very much agree with the above but I have also read that Oak doors should not be subjected to the elements. They should be protected by a porch of some description or recessed somewhat to provide that protection.

 

[jfb]

Thanks for all your advice.

 

Still undecided of course!