Options for oak beams

[overlander matt]

We have some oak beams in the attic rooms in the house. In three of the four rooms the beams have been painted and look pretty ugly. In the other the beams have been varnished but show signs of historic woodworm damage. The beams have suffered some rot around the dormer windows too.

I would really like to strip the paint off the beams and have a bare wood finish but I suspect there is a reason the beams were painted originally - woodworm damage...

What are my options for stripping the paint and not damaging the beams excessively? I paid for a trial from a dry ice blasting company - this tends to be a popular option in the historic property world at the moment but they found this was not suitable for our beams. The timber tended to disintegrate where the woodworm had been. They did manage to clean off one beam and I have attached a photo showing the end result - it's ok but you can see damage particularly close to the corners.

Is there a more gentle option eg chemical stripping, that we could try on the other beams? I've seen stripped beams with woodworm damage without being torn apart by the blasting so guess it must be possible (unless of course these beams had never been painted!). We may however just need to accept bare beams are not going to be possible and look to fill and paint them again (not gloss paint!!). Just wondering how others have got on with their beams.

All ideas very welcome.

Thanks,

Matt

 

[Flyfisher]

Our attic timbers are limewashed. I'm not sure if this has a protective effect but they are all in remarkably good condition considering how bad the actual roof covering was before it was repaired (mostly due to rotted battens and slipped pantiles etc). You can just see a repair on the LH purlin where water ingress above a dormer window led to localised decay of the purlin, which I strengthed by fixing a length of oak into the solid parts of the purlin, bridging the decayed area.

With plenty of water and scrubbing most of the limewash can be removed, leaving an attractive 'limed oak' finish, though I think I'll eventually just put on another layer of limewash when I eventually get around to it. Limewash also has the benefit of brightening up the attic space.

 

[TheSpid]

We used soda blasting and it worked out very well even on the edges of beams that had historic woodworm. Klingstrip is also a possibility for paint removal off beams we haven't tried it but know of those who have had success with it. Sorry pics are from my fireplace renovation album - I can up load more tomorrow if needed.

They went from this black

to this

 

[Toby Newell]

You may find a few of my posts on this... along with some irate people who do not like to read facts...

I don't think the ice blasting looks that bad in your case, whatever method you use there will be some damage to the friable areas, soda blasting may or may not be slightly better, you would want to brush off the friable areas anyway with a stiff brush of your choice, nylon / bronze / steel.

I sand them if they are being clear finished as it gives a smooth surface but if you are painting with a matt black paint or white lime wash maybe the slightly rough textured surface of a blasting technique might actually be better.

 

[MikeG]

I'd say that was operator error, Matt. The friable stuff was left on my timbers after dry ice blasting. (Timbers, BTW, not beams...........beams are horizontal only. Posts or studs are vertical. If you refer to old wood in period properties in general terms it's "timbers" ).

 

[overlander matt]

Thank you for your thoughts on the timbers (thank you Mike!) ... The question is what to try next for the various beams?

One room has been fully stripped and although the beam in the previous photo looks ok-ish there is another that looks a bit rough round the edges where the woodworm has been blasted to bits. How inappropriate would it be to cut this out and put a beveled corner on the beam where there is damage? In this room we will keep the bare beams and tidy them up as best we can. Is a sander appropriate to tackle this?

A photo below shows a room with white painted timbers. We stopped the blasting before any significant damage was caused here having tested a small section on 3 timbers. This is potentially a great room with some nicely stripped beams but I wonder what the best approach is now. It's interesting to hear Mike think this is operator error - I've no prior experience with this techniue so would be keen to hear what could have been done differently. Given the outcome with this company, is it worth trying another, maybe with soda blasting? Alternatively, what about the Kling strip or is this too messy? I had read Toby's earlier post about cleaning timbers and can understand his point of view having seen the blasting in action. I'm back at square one in this room with no significant damage done to the timbers.

The second photo shows the first timber that was blasted. It is quite a mess at one end and I am keen to know what options I have - I'm not averse to painting them again albeit not in a thick white gloss.

The final photo shows a timber that is varnished with clear evidence of woodworm. We didn't touch this one but ideally we would like to strip this.

Ultimately, I'm disappointed by the outcome of the blasting but hope there is still an option to get a decent finish on the beams.

Thanks.

Matt

 

[masochists-r-us]

I can't tell from your other photos, but the first one you posted looks very much like elm to me and might also explain the damage. We have found that old elm is much more susceptible to worm damage than oak and the worms tend to damage under the surface of the wood so you can't see how badly it is damaged until you blast it with ice ! A good reason to avoid this method if you have a lot of elm beams.
For superficial damage, we would live with it, but a coat or two of clear Osmo oil would keep it looking quite natural and reduce the friable nature of the wood. If damage is more extensive, but superficial and you simply can't live with it as it is, you could use wood filler and paint. If the beam has been so badly damaged to have compromised it's structural integrity, you should replace or support it with a new one made from reclaimed timber or new air dried or green oak.
For further info we would recommend The House Restorer's Guide by Hugh Lander. It may be out of print, but you can get a copy from Amazon.

 

[overlander matt]

Thanks for your thoughts on this one. I've been ignoring the timbers for the past week. I will play around with the stripped one in the coming weeks and see if there is a reasonable finish to be had once the worst of the worm and blasting damage has been tidied up. The other rooms are most likely looking like they will be rubbed down and repainted - it just won't be a horrible white gloss this time.

Thanks for the book tip too Massochists R us.

Matt