Ask An Expert

Home » Expert Advice » Ask An Expert
Question

I am a builder for new homes. We did hand over a brand new brick veneer home 12 months ago to one of our clients with solid timber floor cover for the first level upstairs. After one year, my client found some insects coming out from the timber flooring upstairs. It looks like powder post beetles but we are not sure. The house has five rooms upstairs and there are couple of spots in each room are damaged by these beetles. We would seek your professional advice to identify this issue for us and how can we solve it.

Looking forward to hear from you soon and thank you for your cooperation.

Woodsolutions Answer +

It certainly sounds like a case of lyctid borer, aka 'powder post beetle'. This insect produces very fine dust, similar to talc powder or flour, and leaves exit holes of 1.5 to 4.5 mm. It only attacks the sapwood of certain hardwoods. State legislation in Queensland and NSW controlling the sale of timber containing susceptible sapwood has been repealed, but the relevant Australian Standard deals with sapwood in milled hardwood products such as flooring as follows:

AS 2796.1 Clause 2.4 SAPWOOD SUSCEPTIBLE TO LYCTID BORERS

Sapwood susceptible to Lyctid borers shall be immunised against such attack in accordance with AS 1604.

If lyctid borer attack is confirmed, then clearly the flooring in question was not immunised as required by Australian Standard 2796.1, Timber - Hardwood - Sawn and milled products, Part 1: Product specification. If you are unsure whether it's a case of lyctid borer, or your situation does not fit the criteria for lyctid attack, you may need an inspection by a qualified person. 

Lyctid borer

Answered on 09-12-2020
Please note that our answer is based on the best advice available at the time. If the National Construction Code, Australian Standards or local requirements have been subsequently amended, our answer may no longer be correct in all details. For more information, please read our disclaimer.

Question

Documenting alterations to a heritage dwelling in a Sydney harbour-side suburb. Proposing a boarded HWD floor over plywood substrate to the ground floor. Good subfloor clearance, reasonable airflow. Owner is considering infrared radiant heating panels on the ceilings. Considering this type of heating, should we be unduly concerned about excessive movement in the timber flooring?

Woodsolutions Answer +

In the Sydney climate we assume the heating panels are not going to be in use for prolonged periods. Any heating in a closed room has the potential to dry the air a little and hence the timber. However, heating panels at ceiling level are less of a concern than underfloor heating. It might help to guide you if someone could test the moisture content of the flooring. If it's already fairly dry and the building owners are advised to use the heating thoughtfully (eg. don't leave it on all night) we don't see a problem.

Flooring

Answered on 20-10-2020
Please note that our answer is based on the best advice available at the time. If the National Construction Code, Australian Standards or local requirements have been subsequently amended, our answer may no longer be correct in all details. For more information, please read our disclaimer.

Question

Can you please confirm
1. Where in the NCC or the Australian Standards does the requirement for solid floorboards to be directly nailed as opposed secret nails, because of it's width. exist please?
2. Is there a legal minimum length in the NCC, or an advisory or AS for a legal minimum length, for a floor board.
3. Is there any governing code or standard on allowable colour variation in a floor?

Woodsolutions Answer +

1. Nailing of floorboards is covered in Australian Standard 1684, and therefore by NCC 2019, since AS 1684 is a referenced Standard. The relevant clause specifies that "Boards up to 85mm cover width [ie. excluding the tongue] shall be fixed by face nailing with one or two nails or shall be secret-nailed with one nail at each joist....Boards over 85mm cover width shall be fixed with two face-nails at each joist". 2. Regarding the minimum length. AS 1684 states "Board lengths shall be at least the equivalent of two joist spacings". Butt joints must also be staggered, ie. not to occur in adjacent boards on the same joist. 3. Colour variation will be more pronounced in some species than others. Australian Standard 4786-2005, Timber Flooring, Part 2: Sanding and finishing, advises that "Timber floors will contain a degree of colour variation resulting from the natural features of the timber". Aside from that fairly obvious statement there are no attempts in Australian Standards to regulate colour variation in flooring. Specifiers of flooring could obtain some indication of likely colour variation by visiting home display centres and/or by talking to suppliers.

Flooring

Answered on 20-10-2020
Please note that our answer is based on the best advice available at the time. If the National Construction Code, Australian Standards or local requirements have been subsequently amended, our answer may no longer be correct in all details. For more information, please read our disclaimer.

Sign up or Login to continue reading the answer.

Displaying 0/0

Show me 10 /20 /30

Haven't found what you're looking for?

If you have not found the answer for your question in the Search results, please  send us an email for a prompt response.

EMAIL YOUR QUESTION

Are you looking for a supplier?

Social Media Feeds