Another gable end question

[livias]

Hi all. I have been lurking for a while and this is my first post here

I have a black painted wooden barge board on the gable end of my house which is rotten and as there will be a scaffold against the gable this spring seems like a good time to replace it. The house is listed and 15thC and the gable is east facing with full morning sun.
The gable end is not easy to access; A scaffold or a cherry picker is needed so I do not want to be repainting at regular intervals and I am wondering what finish to go for.

For 'no maintenance' I like the idea of untreated oak, but I would like to be reassured that it will behave itself, so does anyone have experience of this?
Alternatively, all the house windows and doors are painted with black linseed oil paint which has lasted very well for eight years so far, so I could put linseed oil paint onto treated softwood
Or something else?

My main concern is the inaccessibility. I want to be able to repair it and leave it. Of course being high up it is not too visible which helps.

Any experiences?
Livia

 

[LadyArowana]

Hello and welcome, just bumping this up the rankings.

 

[paulb33]

Further information is needed:

What's there already? Although rotten, does it really need to be replaced? You should try to repair it, if its part of the historic fabric.
Grade I, II*, or II? Is LBC required? If so, what does your Conservation Officer say?

As for paint, linseed oil is traditional and long lasting. And, it seems justified by what you have already. You could even add lead too, for aesthetics and longevity. That's if its consistent with the rest of the house and its Grade II* or I Listed. Here you'll need to use a licensed supplier.

I'm told that linseed oil would not be compatible with treated timber. Not sure how accurate that is.

Paul

 

[Flyfisher]

Welcome to the forum livias.

I would expect untreated oak to last at least a lifetime and therefore solve your maintenance concerns but paulb33's points about the listing status are valid concerns.

If you have experience of linseed paint lasting well for eight years then I wouldn't be too worried about requiring a cherry picker to do the work. I hired one last year for some tree work and it was £180 for the day, and not much more if I wanted it over the weekend. So £250 every decade or so doesn't seem too bad.

 

[Penners]

Welcome livias.

Assuming there are no listing complications then, as others have said above, untreated oak should last you for a-g-e-s. The only thing I would add to that is the question of its stability. Oak - particularly green oak - has a tendency to warp and crack over time. It would therefore be very important that the boards are hung with plenty of fixings into a stable substrate. In other words, don't skimp on the supporting framework, nor on the fixing screws (which should be stainless steel).

 

[88v8]

Hello and welcome.
If you update your Profile with your location it will assist in recommending local suppliers.

Here
http://www.vastern.co.uk/
you may be able to obtain seasoned oak of suitable dimension.

Alternatively, on my previous house the barges were softwood, sawn not planed, and creosoted. They lasted a long time.

However, given the choice I would opt for oak.

Ivor

 

[livias]

Hi Thanks all for your comments

The wood is definetely rotten; I patched it up on the first pass over the house but it will not last another five years. I don't think that there will be listing problems, the conservation officer is very happy with what we have done so far. My concerns about green oak are what you say and I am not prepared to pay out for super top quality oak to put on a bargeboard. Interesting that treated softwood has lasted well. I might end up going the treated softwood and linseed oil paint route which would probably have the advantage of being cheaper

Livia

 

[Penners]

you may be able to obtain seasoned oak of suitable dimension.

I'm not sure that the extra cost of seasoned oak would give much benefit. In this application the wood is going to be wet and dry, hot and cold, on and off, for all of its life. So - seasoned or unseasoned - the oak (or any other timber) will still need to be well fixed in order to minimise warping.

 

[paulb33]

photos are always v welcome

 

[Keithj]

The catch with green oak is that it shrinks enough to be a problem in the first three years or so. Our gable end repairs looked lovely when they were done. There are now 2-3mm gaps in several places, through which water comes in. I've spent a lot of time with my little pots of lime, forcing it into the lime/oak gaps, covering while it carbonates, and then limewashing over. That bit looks fine. Where the new oak meets the other timbers in the house, it's not such a pretty sight. I wonder if we're going to have a mini-floorquake at some stage when the floor timbers drop to the new level of the oak at the gable end that's supposed to be supporting them. At the moment, I think they're held up by art and/or the middle timbers.

"All green oak" may have been OK when building anew, but green oak with the 500-year-old oak of the rest of the house hasn't worked too well. I'm sure there are other reasons why both the CO and the builder insisted on green, but if I were doing it again I'd ask some forceful questions.

 

[Penners]

The catch with green oak is that it shrinks enough to be a problem

But isn't that a problem that can be resolved by increasing the lap of the boards? Broad principles suggest that green oak will shrink by about 7 - 10 per cent across the grain. Shrinkage along the grain is usually minimal.

It is, of course, impossible to be more precise than this because shrinkage will vary a fair bit according to the individual piece of timber and its environment.

 

[Keithj]

If they overlap, indeed it can. My problem is with structural timber that's shrunk away from what it once supported.