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Like to know what wood to use building a pergola or framing a barn? How about the difference between tung oil and polyurethane as a floor finish? How to revive decking or deal with merbau stains? Or how to meet the building code or bushfire standards? Or ask about the environmental advantages of wood or forest certification?

Q. Hello Could ballpark prices for mountain ash, spotted gum and yellow stringy bark at the sawmiller or wholesaler stage be penciled? With kind thanks

We weren't sure if you were a buyer or a seller, but either way we are sorry we can't answer your question since we don't get involved in pricing. As a seller it's your responsibility to work out your own prices taking into account production costs and other factors. As a buyer you need to shop around suppliers in your area to find one that suits you. The days are long gone when industry sectors set prices, or "recommended" prices.

Q. Can you please point me toward infromation relating to bending hoop pine. I have a laminating project using hoop pine however from the literature I have read it appears you cannot steam bend hoop pine. What are the recommended alternative methods for bending hoop pine?

CSIRO tested a number of timbers some years ago and hoop pine was rated "poor" for bending, slightly better than the lowest category which was rated "bad". You could still have a try and might succeed, depending on the thickness you are trying to bend, and the radius of curvature. Make sure you select material that is straight-grained. If it doesn't work, laminating thin pieces is probably the best alternative. This is how tennis racquets, skis and other sporting goods used to be made. Thin laminations are glued together and then pressed to the required curve before the glue cures.

Q. My house has baltic floor boards on joist which are approx 600mm -800mm above ground on stumps. Can I soundproof underneath the floorboards between the joists? If so what is the best material/method. I want to reduce the outside noise of walking on the floor boards. (to help the neighbours).

There are various ways of soundproofing timber floors, mostly aimed at reducing sound transmission from an upper floor to a lower floor. In your case there is no occupancy below the floor so it seems less critical. If it's only to please the neighbours, simple techniques should help. We suggest installing insulation batts between the joists, supported on chicken wire or similar. If tightly fitted they will help to deaden the sound and have the added benefit of improving thermal insulation of your house.

Q. I am interested in pursuing a career in the timber industry. I am seeking information as to where and how I may best pursue and obtain a carpentry apprenticeship, and I would be greatly appreciative of any information you may have to give regarding this matter. I am 28-years-old and my background is in manufacturing, warehousing, transport and logistics. Thank you for your time and I look forward to your response.

There are two main avenues to pursue a carpentry apprenticeship, one through TAFE and the other through organisations such as the Master Builders Association. If you contact these bodies, or search for info on the net, you will find some helpful information. Various construction companies also provide apprenticeships, depending on which State you are in, eg. Brookfield Multiplex, etc. Again, if you search the net with the key words "carpentry apprenticeships" you will find some leads.

Q. I have an enquiry about my roof frame, it was built and left uncovered for 6 1/2 – 7 weeks, and I want to know if being exposed to the weather for that amount of time will have caused any damage to the wood. Treated Pine was used. I am located in WA. Also I have LVL's that will be permanently exposed to the weather.

We don't expect any problem with your roof timbers, or the wall framing, after 7 weeks' exposure. Timber framing can be exposed for much longer without any adverse effects. For more detail about timber framing exposed to moisture we suggest you refer to our Design Guide #12 titled "Impact and Assessment of Moisture-Affected Timber-Framed Construction". It can be downloaded via this link: Regarding your LVL's, there are strict guidelines regarding their use in permanently weather-exposed situations. If made from pine they must be preservative treated and moisture excluded as much as possible. The data sheet published by Carter Holt Harvey for their hySPAN LVL product is a good guide. It can be downloaded by pasting this link in your browser:

Q. I am currently writing a chapter in a report of surveys we (Geoscience Australia) have undertaken following the 2011 and 2013 Brisbane floods. I have data on the time taken to dry the frame after the removal of wet linings (and the consquent problems mould, cracking etc). I have seen CSIRO sourced info on estimated drying times of timber framing (weatherboard and brick veneer) during winter in Sydney (5-7 and 9-22 weeks). But they do not have any Qld related data. Do you have any information re similar drying times of dwelling frames for Brisbane in summer?

It's difficult to put a figure on the time required to dry a timber frame after flooding. With regard to the CSIRO data, saying it might require 9-22 weeks doesn't help someone doing a survey, it just shows how elastic the figure is, and no doubt this is what CSIRO was trying to highlight. The drying time will depend on the weather at the time of year, level of ventilation, and the location of the timber in the frame, with bottom plates likely to be wetter than top plates. We have a technical guide that might help. It's Design Guide #12 in a series and it can be downloaded via this link: We draw your attention to clause 1.2.1 of the guide which recommends the use of an electrical resistance moisture meter, fitted with a hammer probe. That's the only way to monitor drying and to tell when the process is completed.

Q. We are looking at putting bluwood down for bearers under a new floor that we are putting down in a house. (The previous floor, bearers and some of the joists had been eaten by borer). One of the owners is concerned about potential toxicity effects of the chemical treatment used to create bluwood on people who may live in the house, eg pregnant woman etc. Can you please some advice on this re the bluwood product? Could you please advise on what the chemical is that is used to make bluwood? Would you be able to send me the chemical safety data sheet for it? Do you have any other suggestions re safer products used to pretreat timber for borer?

The timber you refer to is marketed under the "umbrella" name Blue Pine, but each company has its own brand name, eg. Pinegard Blue, Terminator Blue, Timberlink Blue, etc. and each company has its own Material Safety Data Sheet. You can find these on the net if you write Blue Pine MSDS in your browser. The chemicals used are either bifenthrin or permethrin, depending on the producer's preference. You can find more information about these chemicals if you write their names in your browser. We have no medical expertise but consider it most unlikely that there would be any adverse health effects from coming into contact with Blue Pine if used as recommended, ie. avoiding inhalation of wood dust (something to avoid whether timber is treated or untreated).

Q. Owner is concerned about black surface mould on timber please advise if any treatment is required prior to lining house with plasterboard.

Moulds are everywhere in the environment and spore counts are typically higher outdoors than indoors - that is why sensitive individuals are directed to stay indoors when spore or pollen counts are high. When we say "moulds are everywhere" we mean the spores are everywhere, and only develop into visible patches of mould when they land on a suitable substrate, eg. damp wood, steamy bathroom walls, etc. In the case of timber framing, moulds stop growing when the moisture content of the wood drops below 19%, as will happen once the house in question is enclosed. In a dry wall cavity or ceiling space the moisture content of timber stabilises at around 12%. At that stage the mould will die and in any case will be physically separated from human contact by the wall and ceiling linings. Taking all this into account we don't see any need to treat the timber since the mould will die without treatment. However, the timber framing should be allowed to dry out before plasterboard linings are installed.

Q. We have just bought a 60s fibro house on the Mornington Peninsula and are planning on renovating and extending. In the short term we are getting ducted heating under the floor as the house is really cold and hard to heat effectively with the heater we currently have. We are wondering how we can make the ducted heating more effective by adding insulation to the floor, and whether this should be done prior to, or alongside, the installation.

It will probably be more cost-effective to insulate the floor in conjunction with the installation of the ducting, since workers will be operating under the floor and might as well do both jobs. If you have to engage two separate companies it will be best to install the ducting first. If insulation is installed before the ducting it will be disturbed when the ducting is installed and will make the job more difficult. There are several ways of insulating a suspended timber floor and you will find some of them described on the net, for example the Bradford Optimo system at this address:

Q. We have a problem with our 3-year-old kitchen veneer drawer-fronts which the installer refuses to acknowledge. It appears to be a moisture issue. How do I contact an independent assessor to do a moisture reading on the core timber and veneers? I have tried but the page won't load.

We understand that the Timber Inspection service in NSW is having a temporary problem with the website you mention. It's expected to be rectified shortly, but we suggest you contact one of the inspectors directly on 0429 646 112, or by email at


Did you know?

In 2008 seventy percent of known old-growth are in nature conservation reserves.