Timber and insect attack

[Charlie Woody]

I bought some oak and elm from my usual supplier two weeks ago and going through the paperwork today I noticed (which I had not seen on his invoices before) "It is recommended that all timber should be treated against insect attack"

Is this necessary even if I will be treating the finished items with either Osmo or Fiddes hard was oil? If it is necessary what should I use to treat it that will allow me to still use these oil finishes?

On the elm waney edge in the sapwood I did notice a few small holes which I guess could be insect holes - what should I do please?

 

[G S Haydon]

Hello Charlie,

Normally worm would not go for the heart wood but would chow down on the sap. That's true for oak at least. I try to avoid any pale sapwood in oak work for this reason. If you are worried you could give it a coat of cuprinol clear preservative to make it less tasty for the bugs. Try and avoid 5 star cuprinol as it prevents other coatings going off or bonding IME.
The advice above is based on using the wood in an external context.

 

[Charlie Woody]

Hello Charlie,

Normally worm would not go for the heart wood but would chow down on the sap. That's true for oak at least. I try to avoid any pale sapwood in oak work for this reason. If you are worried you could give it a coat of cuprinol clear preservative to make it less tasty for the bugs. Try and avoid 5 star cuprinol as it prevents other coatings going off or bonding IME.
The advice above is based on using the wood in an external context.

Thanks for that. It's for indoor furniture - oak and elm. Should I get rid of the elm sapwood asap?

 

[G S Haydon]

If its internal work it's a tough call. I would remove the bulk of the sapwood, although leaving a flash on the edge is no bad thing really depending on your project. Just don't blame me if the woodworm eat your house..........Joking

 

[Chrispy]

You don't say what kind of timber supplier you have, normal modern kiln drying should kill off any infestation in the wood but it could still be attact afterwards if your supplier has a low turn over and tends to keep wood for any length of time after kilning. so it could be a get out clause to stop you sueing them if you are eaten out of house and home because of their wood!

 

[rafezetter]

in US they use a dilute spray of borate soaked into the wood which deters insects in timber frame buildings, however I have no idea if this will have an affect on the wood itself or any finish you might use on top..


hmm... - ok here's what I found: http://www.thefreelibrary.com/Surfa...mpregnated+with+borates+before...-a0209801575

oh and it has a side effect of making it virtually fireproof too - which is nice.

 

[Charlie Woody]

You don't say what kind of timber supplier you have, normal modern kiln drying should kill off any infestation in the wood but it could still be attact afterwards if your supplier has a low turn over and tends to keep wood for any length of time after kilning. so it could be a get out clause to stop you sueing them if you are eaten out of house and home because of their wood!

It is a small supplier who kilns his own supplies of timber plus some purchased from local landowners etc. It is possible that the timber could be out of the kiln for some time and stored in controlled conditions.

Do you think I should apply some sort of treatment that would be compatible with the Osmo / Fiddes, or will the finish provide enough protection?

 

[longinthetooth]

Unless you are clinically paranoid, and having excluded sapwood by default, I wouldn't use insecticide on an indoor product - there are enough chemicals in the environment already.

 

[johnwc812]

Hello Charlie
I suggest a chat with your supplier, see if it is just to cover himself, or other customers have complained about insect infestation.
He may even have a suitable insecticide that he buys in bulk and let you have some.
Cheers John

 

[Andy RV]

I'm currently in the process of buying a house that has had woodworm in the past so I've been doing quite a bit of research after the surveyor came back recommending all sorts of specialist surveys. One piece of info that I learnt is that the bugs like wet/ damp wood and any wood dry enough to be used for indoor furniture should kill them off. I'd rip of as much wane as you need to then see if the holes continue further in, hopefully they won't.

 

[Charlie Woody]

Just an update. I spoke to the supplier and he said their solicitor advised them to put this on their invoices as they cannot control what happens to the timber once it leaves them i.e. it could be placed in an infested environment. He said that they have never had any problems with insect attack.

 

[custard]

If you live in a house that's dry and has central heating then woodworm is nothing to be worried about. Once wood is at the 12% moisture content (or lower) that it will settle at in a domestic environment it's just too dry to sustain boring insects and they die, so even sapwood and vulnerable timbers like beech or soft maple are safe.

 

[sawdust1]

Hi custard, what about woodworm attack on furniture, thats dry wood indoors with central heating ?

 

[Random Orbital Bob]

I must say I've never known any of my indoor furniture to get beetle attack, not in a modern centrally heated house. Antique furniture....sure. But that was subjected to damp, drafty cottages etc where the only source of heat was an open fire.

 

[custard]

Hi custard, what about woodworm attack on furniture, thats dry wood indoors with central heating ?

Bob's right, any worm holes you might see on furniture in a modern centrally heated house are either historic (antiques), or possibly occurred when the timber was air drying. I'm working with some sycamore at the moment that has one or two worm holes, but I'm not worried about building furniture with it as the insects concerned are long dead and couldn't survive in a dry home.

 

[custard]

Here's a useful link, it's written from the perspective of picture framing but it obviously applies just as much to furniture,

http://theframersforum.com/download/file.php?id=4942

 

[Sgian Dubh]

Common furniture does not attack live wood in trees or wet unseasoned wood stored outside—it likes cool, damp conditions where RH remains at about 55 percent or above. It will breed in dry dead branches of trees, fence posts, air dried wood stored in sheds, et cetera but objects and structural wood in centrally-heated buildings are very unlikely to support woodworm infestation. Just because warm and dry internal conditions deters the beetle this does not stop it attacking roof timbers and sheltered wood under eaves, soffits, porches and so on.

Dry wooden furniture, eg, indoor residential furniture that never gets above about 12% or 13% moisture content, and frequently dryer at 6% or 8% MC is a particularly harsh environment for common furniture beetle to survive. Research and data suggest in fact that 12% is the lowest wood moisture content at which newly hatched furniture beetle grubs can exist.

I am always rather wary of furniture or wood that has been stored, kept or used in and around such locations as gardens and their sheds, warehouses, farm buildings, et cetera and much less wary of furniture that has a long known history of use in a warm and dry house. I have for example experienced customers that brought in furniture for repair and I discovered upon examination evidence of recent woodworm activity. Further questioning of the client usually brough to light that the furniture had been stored, sometimes for years, in an outbuilding, cellar or furniture repository whilst they decided what to do with it or moved house. Buying old or antique furniture at auction is a good example where it is prudent to check for woodworm activity after purchase, or if a customer brings an auction purchased item in for restoration or repair—you just don’t know where the furniture was stored in a past life. Slainte.