Woodworm treatment

downshifted

Our survey showed evidence of live woodworm in garage - on shelves - and none elsewhere - the following is to treat the timbers in the garage and preventative treatment in the roof of a 2 bed bungalow including where appropriate removing of insulation and preparation of timbers

Garage £150
Main roof £456

Optional guarantee insurance £47.25

Is this about right please?

David_Aldred

Hi downshifted,
The fees quoted seem typical though you might want to consider whether or not the 'woodworm' infestation is actually live or not as spraying with insecticide will not make the emergence holes disappear and the treatement will be ineffective on anything other than bare wood (i.e. wood that is clean and free from paint / varnish / other coatings).

Treating of an insulated loft void would require prior to treatment removal of the insulation and industrial vacuuming of all debris if an active infestation were present here. Allowance should be made for this and not simply rolling the insulation over which is often done to cut down costs. Allowance will then need to be made for new insulation to current Building Regulation standards and likely increased roof ventilation. Further allowance should be made for protection of services within the area of treatment such as the hazard of spraying electrical cables and junction boxes which with some insecticide products can not only cause an electrical fault but also degrade as a result of treatment.

Treatment of timbers within a property is only ever likely to be partially effective as not all timber surfaces can be reached and some timbers would require dismantling if all their surfaces were to be treated.

Common furniture beetle often referred to as woodworm by the public fly and if present in the loft void of the house and the garage it would be prudent to budget in your purchase negotiations for treatment of other areas until proved otherwise such as suspended timber floors which may well not have been inspected throughout.

I would ask to see a live beetle obtained from that house as proof of an active infestation as simply looking at dead beetles / the emergence holes / bore dust / frass (the poo from the insects as it eats the wood) is no proof of an active infestation at all.

Spraying insecticides is not an instant kill of all wood boring insects throughout the timber as the insecticide only penetrates a few millimetres. As such if an egg of such insect is laid this year just prior to treatment it could eat and damage timber for several years after insecticide spray before it emerges from the wood to breed and hopefully comes into contact with the long lasting insecticide.

Permanent warning notices should be placed in the area treated stating what product was used, date of treatment, area treated, full contact details of who treated it and full contact details of product manufacturer to warn anyone entering the area of the hazard. Not a complete list of things to be aware of by any means but hope this helps, kindest regards David Aldred Independent damp and timber surveyor.

downshifted

Many thanks for your comprehensive reply :-)