Woodworm Case Study

Wood worm "Hope Vs Experience"

We were asked to take over the refurbishment of a house in central Portugal. This is always difficult because although there appears to have been lots of work done there is always an element of work having to be rectified. In some cases a large amount of work has to be redone.
When I was serving my apprenticeship. My old boss used to walk around a building with a piece of chalk and a sharp electricians screwdriver, He would stab the screwdriver into skirting's, floors, architrave and doors basically any timber he came across. Anything that didn't give the correct amount of resistance to the screwdriver would be marked with a chalk cross. We would then have to cut it out, remove it from the building and burn it.
The insects we were treating were the Common Furniture Beetle, Death Watch Beetle, Powder Post Beetle and House Longhorn Beetle.
Everything that was left would be given two applications of wood worm killer. Normally on a Friday or Saturday so the fumes wouldn't be too bad when we resumed work.
Back in those days there was no care taken if bats were found or birds were nesting we just stripped out what we were told. Now that I look back I can see that there was no care taken for the workers either!. No paper overalls vapour masks or gloves. No water based treatments Just a wash afterwards if you were lucky.

Back to the present day refurbishment.

Looking at the partially replaced first floor in image 1, right. You can see a large dimensioned wooden beam running between two massive stone walls and supporting new pressure treated joists.
All appears well at first sight.
We were working to re-level the floor joists when we became suspicious of the central beam. Assured by the owner that it had been treated with wood worm killer as was plenty strong enough to support the new first floor and bathroom. We drilled a few small exploration holes into the beam and our suspicions were confirmed for the worse.

The pine beam, probably not part of the original house had at least 50 years of wood worm happily munching through the central area of the beam. There were plenty of exit holes to be seen however the real scene of devastation was on the inside.
NB: in a house of this age and quality the support beams would have been the trunk of a chestnut tree or ash tree which has a natural defence against insect attack. They are also remarkably strong unlike pine.
With more than 70% of the core timber missing it was only a matter of time before the beam broke with the possibility of bringing the stone wall down around it.
You can clearly see in the photographs of the centre of the beam large hollow areas.

It is virtually impossible to tell the strength of any insect infected timber unless you can see a cross section or at the very least examine the interior at regular spacing's by drilling holes
Let us use our experience to assess the problem and supply the remedy to your woodworm. In the UK there is one name synonymous with woodworm treatment - Rentokil

Their website has an interesting page on Treating Woodworm.

"What is Woodworm?
Woodworm is the collective name for a number of species of Wood boring insects that attack wood. Common woodworm beetle and include the Common Furniture Beetle (Anobium punctatum) and the Death Watch Beetle (Xestobium rufovillosum). The term "woodworm" refers to the larval or "worm" stage of the insects' life when they bore and eat wood.
Woodworm can attack wood within the structure of a building and even the wood within your home furnishings. If left untreated, woodworm can seriously weaken timber leading to the eventual failure of the structure of a building.

How To Identify Woodworm
Woodworm beetles and wood boring insects use wood as a food source or as a home and they often leave signs of their presence such as:

A few more culprits which you may not of heard of:

A little good news/bad news:
Introducing the Steely Blue Beetle - Korynetes caeruleus
Appearance, Adult – 4mm. Shiny blue colour. Its larvae live inside wood that has been already infested by wood boring insects, where they feed on the larvae of these wood-damaging insects such as the common furniture beetle and death-watch beetle.

The not so good news:
Its presence indicates a heavy infestation of wood boring insects.

Time to bring the professionals in!

Contact woodworm@casteloconstruction.com Or call us on Skype casteloconstruction
Telephone 00351 967 922 513
Key words refurbishment central Portugal Common Furniture Beetle, Death Watch Beetle, Powder Post Beetle and House Longhorn Beetle.