Woodworm treatment in roof timbers

modelreject

Okay. Ask what they will be using and they said Permethrin. They spray nearly every day and say that it is safe enough. I'm hoping they are right.

David_Aldred

Hi - my father died of asbestos 30 years after he ceased being exposed to it and despite wearing what was then deemed appropriate as a breathing mask to prevent inhalation. The mask was later deemed to be ineffective - if you have ever watched anyone die of mesothelioma it is not a very nice way to go I can assure you. I could only conclude that what was deemed safe a while ago long term monitoring showed it to be anything but with tragic results in the case of asbestos related disease.

The articles / links I posted above simply illustrate general concern over the insecticides that have previously and are in some cases still being introduced into properties. I neither agree nor disagree with them they are just given for information of people on the forum to make their own mind up but I am interested in the topic of what is often referred to as the 'toxic box' of chemicals introduced into properties over time and how this may affect the well being of those exposed to them either in the short or long term.

I feel this is reflected in the way that the country is generally moving to a far "greener" approach to the treatment of timber decay, dampness and wood boring insect control which one would hope people would generally agree has to be a good thing if it reduces health risks not only to those working with such chemicals but also those innocently exposed to such a cocktail of what may be several different treatments such as occupaants and third parties working within properties.

From what I have read up upon the matter and talking with consultants to date is that there remains some concern over the use of chemical treatments within properties and how those that were previously used and are now banned may react with those currently in use and so we must try to learn about these issues as best we might and in the meantime fully justify the use of chemicals introduced.

In the case of woodworm infestations I would simply conclude that the home owner ask to see actual live beetles and / or larvae in significant numbers from those inspecting before they accept an opinion given by such persons that the infestation "appears to be" active. The presence of flight holes / dead beetles / frass (the bore dust) in no way confirms the infestation is active at all - ask to see living proof! If there is only suspicion of activity then monitor the area for such proof.

The following article on woodworm is also quite informative to those who may be interested:

http://www.icup.org.uk/reports%5CICUP746.pdf

Kindest regards to all, David Aldred Independent damp and timber surveyor

modelreject

Thanks again for the info.

modelreject

Got it sprayed. Hopefully it works. Do you know how long it takes for the blighters to die?

David_Aldred

As previously written, some insects that are on or close to the surface will die immediately upon contact with the insecticide but any larvae below the level of penetration / upon surfaces unable to be reached will live on for varying lengths of time which could be up to 7 years until hopefully (for you that is - not the beetle) they come into contact with the insecticide during emergence. Kindest regards David Aldred Independent damp and timber surveyor

Dry_Rot

Hi Modelreject.

Well done. Consider them dead, for all practical purposes. If the surface has beed sprayed to 'run off' the post treatment emergence is a minor problem. Whilst the odd beetle may escape, if it emerges through a hard to get to bit of wood, which was shielded from treatment. The timber cannot be re-infested.

David_Aldred

Hi Bryan,
Now that we have called a truce you will agree that the larvae below the level of insecticide penetration will remain alive and therefore eating the wood unless they come across the insecticide which could take a number of years as confirmed by Building Research Establishment (BRE) publication "Remedial treatment of wood rot and insect attack in buildings" states "larval activity (and with highly active attacks,signifiant structural damage) may continue for possibly several years after treatemt" but I take your point that if done correctly the client should feel confident no further insecticide treatment should be required. All the best - Dave

Dry_Rot

Yes - a truce is good because we can concenetrate on helping forum members. However, we both appaerently yearn for the last word - as demonstrated by the last post. What I think your saying is yes, that's right?

A very heavy infestation, which could cause structural damage during the last life cycle, shouldn't be being sprayed anyway. If the treatment has been specified by a qualified and experienced surveyor, I'd take it as read that the infestation has been deemed slight to moderate and is suitable for spray treatment.

modelreject

Thanks very much again guys!!

modelreject

Found a couple of dead wood beetle on top of bathroom tiles beside sink. The infestation was above the bathroom. Do wood beetle move slowly, fast, fly?