Final clean up of ancient timbers (internal)

[sue gazzard]

I am v pleased with Kling Strip for removing thick layers of gloss from the timbers in my building, and am planning to send all the doors for dipping (unless you all scream at me). My biggest problem is in one of the cottages which had layers & layers of wallpaper over wattle/daub/barley straw/timbers, the lot. Most of it has come off but the residual glue/bits of paper/dirt of ages is troubling me. Every builder suggests to sandblast using fine grit (though one did suggest something called 'joss' but I can't find any ref to it anywhere. Any clues??)

I am worried about damage to the infill as well as the timbers, and would prefer to deal with it myself just because i think I'll take more care. Is it time for wire wool, elbow grease, and....what? hot soapy water? I just don't know but I bet loads of you do!

 

[Nemesis]

SCREAM:

DON'T DIP!!!!

DON'T BLAST!!!!!

 

[Ian Bond]

I'll second that.

I would no sooner send off a door to be dipped than do the same to a fine piece of Georgian furniture!!!

The joints could become loose, the door could warp, panels could split (assuming this is a panelled door, not ledged and braced?). The surface of the timber will probably be very rough, nd need a lot of sanding.

I would not use wire wool - you'll get bits of wire embedded in the wall / timber and it will rust and leave marks.

I'd try the gentlest methods possible first, and stop if it looks to be causing damage. It would be better to leave things slightly rough than go for perfection and damage historic fabric.

I've used water, scrapers , green pan scourers, steam (with great care) etc with success. This has removed layer upon layer of paper, paint etc. But it's tested my patience/stamina to the limit (and beyond).

To be fair to the builders, unless you have limitless funds and are paying by the hour, they need to work quickly, with sometimes lamentable results.

 

[Penners]

Don't dip, don't sandblast.

The risks of dipping have already been well explained by Ian Bond. If you want proof, read this thread http://www.periodproperty.co.uk/forum/viewtopic.php?t=8811

Sandblasting is also very risky. It can make oak beams look like driftwood, and it can totally destroy plaster, daub/etc.

I would also follow Ian's advice about getting off the remaining bits of paper, etc. If you need something a bit more abrasive, you might try a softish non-ferrous wire brush.

 

[sue gazzard]

Thanks guys, very grateful for your advice. Guess I'll KlingStrip the doors too! Has anyone come across this 'joss' stuff/method in terms of finishing of timbers & beams??

 

[Penners]

Sue - if your doors are softwood, I wouldn't recommend Klingstrip. It's great on hardwoods, but I've experienced a few problems with it on softwood. It can darken the colour and make the surface of the wood "stringy".

My personal preference for softwood is Nitromors, which you should be able to find in any DIY store.

 

[sue gazzard]

They're ancient, almost certainly oak, I very much doubt they're softwood.

 

[inwood]

I would second Penners comments re Klingstrip on softwood. Maybe I left it on too long but it seemed to open the grain in places, however this was on a pine beam which had previously been sandblsted by a previous owner.

With regards JOS. The 'JOS system' has now been superseeded by the TORC system. There is also the DOFF system. The company that introduced the JOS system is:
http://www.stonehealth.com/machinery.html
They've got a video on their site showing the technique in use on stone.

From what I've read it's an abrasive technique similar to sandblasting but apparently significantly less abrasive. I have no experience but you should be able to find references by searching for 'TORC cleaning' in google.

Here's an article discussing the pros and cons of abrasive cleaning techniques:
http://www.buildingconservation.com/articles/masonry/abrasive.html

The only reference I can find to this being used to clean beams is by this company:
http://www.avvsolutions.com/property_restoration.html

Please be careful when considering cleaning your beams - I've seen a beautiful old oak beam with centuries of patina, invocations to the Virgin Mary in the form of an 'M' and the dents and chips that only come with age reduced to little more than a smooth, bright new beam.

 

[Penners]

They're ancient, almost certainly oak, I very much doubt they're softwood.

Just to be sure, why not scrape a small area of paint off the hinge edge, and have a look at the bare wood?

 

[skier-hughes]

I would second Penners comments re Klingstrip on softwood. Maybe I left it on too long but it seemed to open the grain in places, however this was on a pine beam which had previously been sandblsted by a previous owner.

This will happen on any timber. I spoke to Strippers and they told me to test carefully for length of time to leave the stripper on. The softer and more open the grain the less time you should leave it on, as the quicker it will open the grain up.

Graham

 

[Penners]

Graham

I've never had the problem on oak or elm. I suppose if you left the poultice on for an inordinately long time it might happen, but in my experience only softwood is particularly vulnerable.

 

[skier-hughes]

I don't know how long it might take, but I was asking Strippers because I'd put some on and had to go away the next day so it was on for 2 days and they told me to be careful with leaving it that long due to it casuing the wood to open.
I think older more rough oak would be more at risk than smoother tighter grained wood where it would find it easier to get into the grain anyway.

I think the word is, take care and use caution when using it.

 

[Toby Newell]

Again.

Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Blimey, I can't leave you lot for five minutes....

Klingstrip CAUSTIC ALKALINE, dipping CAUSTIC ALKALINE possibly exactly same substance (Sodium Hydroxide or similar) Oak, ACIDIC TANNIC, o level chemistry ALKALINE + ACID = REACTION = DARK STAINING. Us French polishers call it burning "plaster burns" as plaster is alkaline. Am v glad Penners didn't notice a problem but I would NEVER REPEAT NEVER use an alkaline stripper on oak, on ancient timbers oh my god Aaaaaaaaaaaaaaaaaaaaaaaaaaaa.

Chateaux Margeaux 1900, would Madam be requiring diet or regular coke with that? Seriously as a professional French polisher you could not think of a more heinous crime. Houses of parliament minister court 1841 linenfold carved English oak, some muppet dribbled gypsum plaster all over, nothing we could do, the staining is still there, still visible through the stain we applied on top. You can't bleach it out, you would ruin the oak. Ancient English oak has to be one of the most beautiful naturally occuring materials on the planet, stand around admiring it, photograph it, stroke it but please don't put any caustic chemicals on it!!!

I could go on. Please don't. Phone up your local French polisher (old boy, a decent one with 20, 30, 40 years experience) and tell him what you are about to do, then you can listen to Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa in stereo.

All the best

Toby

ps Nitromors (or strippers own solvent methylene dichloride based stripper for that matter) see my piece in finding out section for advice.

pps just finished stripping 300 yr old elm and oak staircase, inexplicably beautiful, stripped with solvent stripper, no 6 grade wire wool and lots of elbow grease. (And a lucky polisher called Mark whom I let have the pleasure of doing so)

pps Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa. Put it away!

 

[Nemesis]

The problem is, Toby, that you pop up every now and again, go back through long gone posts, weeks and at times months after the original query, and then tell people they are wrong.

Bit late by then as the original poster has probably done the job.

 

[Flyfisher]

On a separate, but related, issue to stripping old wood, I'm a bit confused about the 'heritage' position on all this. Where's the boundary of approval between destroying historic fabric (i.e. the painted finish or other coverings) and revealing the underlying historic fabric.

In various parts of our house, some of the oak beams are painted, some are limewashed, some have been boxed in during (we believe) a 'Georgian makeover', some are original and bare and all the doors are painted.

Is it 'good conservation' to remove some of this in order to let the 'glory' of fine English oak shine out or is it pandering to the 'stripped pine' fashion of recent times which may be historically inaccurate? Or does it not really matter either way?

 

[Penners]

Ooooh - you can't go around asking questions like that, FF! You'll open a can of worms.

What is destructive?
What is honest development?
What is conservation?
What is vandalism?

If an original oak window was removed in 1821 and replaced with a pine one, is that honest development?

If so, then why is it not honest development to take out an original oak window today and replace it with a uPVC one?

 

[Penners]

The problem is, Toby, that you pop up every now and again, go back through long gone posts, weeks and at times months after the original query, and then tell people they are wrong.

But never mind. At least we all get to recognise the error of our ways. Just be grateful that we have an infallible expert in our midst, even for a brief moment.

 

[Nemesis]

Oh, the philosophy of conservation - a can of worms indeed.

http://www.donhead.com/building_conservation_philosophy.htm


http://www.buildingconservation.com/articles/ethics/ethics.htm


http://www.ribabookshops.com/site/viewtitle.asp?pid=7855
http://www.donhead.com/journal_architectural_conservation/jac_12_3.htm


http://www.ribabookshops.com/site/viewtitle.asp?sid=&pid=8435&HID=923


Etc etc etc

 

[Penners]

If you think I'm reading that lot....!

Distil them into a once-sentence answer for me, would you? :wink:

 

[Nemesis]

Nah - nice day, garden beckons...