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I have a listed house built in 1815 with a very old but beautiful timber entrance, this is made with timber hand made columns which have gone quite rotten at the bottom and need treating and repairing.

It wont be possible to chop out and replace the affected items.

In the past I have completed repairs which have lasted more than 30 years but these used pellets, which were inserted into the timber after initial treatment and I don't think these are available now.

Can anyone help me with an effective long term fix to rotten timber restoration please?

Thanks in anticipation.

Hi Chris
I had a very similar problem on my thankfully not listed 1880 house. The structural timbers supporting a bedroom over the front door had been allowed to rot through lack of gutter maintenance by the previous owner. I repaired them nearly ten years ago using Smiths Clear Penetrating Epoxy Sealer: http://www.makewoodgood.com/catalogue-2/cpes-clear-penetrating-epoxy-sealer/.
This soaks right through the rotten or softened timber and leaves you with epoxy impregnated timber. it can penetrate through great distances of timber, and flows astonishingly well indeed along the grain.
To repair columns, assuming that your rot has started at the bottom, I would suggest making a moat around the bottom of the column, using plasticine, or perhaps even expanding PU foam (which may be too hard to clean off of the surrounding substrate, test first), and then filling that moat with the Smiths CPES. This will be wicked up through the rotten timber, keep filling the moat till no more is absorbed. Leave this to evaporate the solvents, and then repeat again (twice more recommended). This will leave you with a permanent solution, and timber that is significantly harder than the original.
Let me know if your rot has started somewhere other than the base.
The finished surface can be painted, or filled if a profile has to be restored using Smiths Epoxy Filler Fill-It.
Hope this helps.

Thanks for the advice, much appreciate.

I was planning on using a wood hardener but hoped to use the pellets I used many years ago given their effectiveness, I suspect that these are no a banned substance as I do recall very tough warnings about their use.

Do you think wood hardener will be okay on its own as I'm concerned about future rot given the exposed location and thought a serialising agent might be needed as well ?

I have noted pellets produced by a company called Boron, See http://www.boron.org.uk/Boron_shop_goog ... #Boronrods

I might use these as a supplement to your suggestion.

Thanks again.

Kind regards

C

Hi Chris

Zinc Borate (the chemical in the tablets) is in a different league to the CPES, which will restore significant strength to your timbers as well as stopping the advance of any further rot.
Used as directed you will end up with timbers which are fully saturated with epoxy resin, and effectively fully waterproof. Ideal for being the bottom of structural pillars in fact.
I doubt whether the zinc borate would actually permeate through the CPES treated timber to any significant degree, although I have not tried using the two of them together.
Steve