House Longhorn beetle on piece of wood

House Longhorn Beetle: Signs, Treatment and Prevention

23 March 2022

The House Longhorn Beetle, also known as Hylotrupes bajulus, can cause serious damage to timbers within any property. These beetles are usually found in areas in the South East of England. The more specific locations that these beetles have been found in are London, Sussex and Kent. The 1920s and 1930s were the time frame that House Longhorn Beetles were found to be commonly infesting properties.

What Does a House Longhorn Beetle Look Like?

Just like other woodworm beetles, this insect will start to infest surfaces that are damp. They are approx. 8 to 25 millimetres in diameter and can either be brown or black in colour. A recognisable trait is that the head and body are covered with greyish coloured hairs and two shiny black spots that resemble eyes.

House Longhorn beetle

The most common signs of an infestation are the exit holes. These holes are 6-10 mm in diameter. The holes left by the House Longhorn are significantly larger than those left by the most common form of woodworm, Common Furniture Beetle.

Damaged caused by the House Longhorn beetle

This insect infects the sapwood of most softwoods, in particular, roofing timbers. If there is a large infestation of House Longhorn Beetles, then you may hear a scraping noise during periods when the larval are feeding especially on the warmer days of the year.

Bore dust will also be left by House Longhorn Beetles. This dust or frass, which is left by the beetle after it has chewed its way through the wood will be cream coloured and when rubbed through your fingers, it will feel gritty.

When Are You Most Likely to Find House Longhorn Beetles?

The larvae of the House Longhorn beetle usually mature in the spring months this is when they cause the most damage to properties. During these months of the year, the insects can move more freely and can then move onto other areas of timber.

How to Treat House Longhorn Beetles?

Treatment for House Longhorn Beetle is much more difficult to carry out than for Common Furniture Beetle (Anobium Punctatum). The House Longhorn Beetle has a long lifecycle, and it is only visible towards the end of its lifecycle. There is a big difference between the treatment of the Anobium Punctatum beetle compared to House Longhorn Beetle.

An example of this is that the treatment of Common Furniture Beetle will involve surface treatments applied by either using a spray or brush which then stops the woodworm from starting a new lifecycle when it has exited the timber. As the beetle’s lifecycle

is shorter than 5 years, it means the holes left by the woodworm are smaller and therefore it is more appropriate to apply the treatment directly onto the surface of the timber.

House Longhorn Beetle treatment will involve additional methods rather than just being applied onto the surface of the timber. This will involve the internal injection of treatments and weekly inspections of the timber. The treatment process will involve:

  • Drilling injection holes to the areas that have been affected by the beetle.
  • Dust will be removed from the holes and then filled with a form of timber injection gel.
  • The holes will then be capped off.
  • Once the holes have been injected with timber gel then surface treatment can be applied.

The treatment process we have described above is quite a difficult procedure and should be carried out by a qualified technician. At Timberwise, we have qualified technicians who will be able to carry out the required treatments to the correct standard. We also provide long-term guarantees that provide you with the peace of mind that your property is in safe hands.

How to Prevent House Longhorn Beetles From Appearing?

The biggest cause of woodworm is the moisture concentration of the wood materials. To prevent moisture from affecting your timber, there are a number of steps you can carry out to make sure your property is protected as best possible from House Longhorn Beetles from arising.

If your house is having an extension or a new part of the house is being constructed, then the wood materials could at some point be left exposed and therefore be prone to dampness. These materials will need to be protected through the use of surface covers.

You should make sure that if you have any leaks in the property that these are rectified as soon as possible to stop dampness from occurring.

Speak to Our Experts

If you are having trouble with House Longhorn Beetles or are any types of beetles that have not been discussed in this article, then don’t hesitate to contact our team at Timberwise.

With over 5 decades of experience in treating woodworm, you can be sure that Timberwise can treat your House Longhorn Beetle problem quickly and effectively. To arrange a woodworm survey simply call 0800 288 8660 or complete our online survey request form.