Here is another question asked by a member of the public relating to timber treatment. We hope that it and the answer, which we include below, are useful.

I have woodworm in the underside of the floorboards and floor joists of the ground floor of my house.  There is a cavity under the house in which I can just about crawl to every part.  Please can you recommend a treatment, bearing in mind the difficulty and health and safety concerns of applying chemicals in confined spaces.

Also the amount I would need to treat a floor space of approx. 5m x 7m.

Here's our answer:

For this application I would suggest Micro 8I. This comes in a 1L container that is diluted to 25L with water. Try to ensure you have as much ventilation as possible and wear a nuisance mask. If you can remove a few boards this will help.

If you have a question, that you'd like us to answer, please email John Oxley: john@constructionchemicals.co.uk

Construction Chemaicals offer a free 'Ask John' service and he will be happy to answer any questions you have.