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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. We have just had a builder add a second floor to our 48 year old house and generally are very happy with his work, the original house was brick veneer and the extension is rendered foam, the original roof and the new roof are tile with new insulation batts, we do currently have one concern that no one seems to be able to answer though: The upstairs addition is about 60% of the size of the original building and the front section is adjacent to the original roof space. When the outside temperature is high (30 deg +) it seems as though the new upstairs floor is heated, I am wondering if the hot air from the original roof would be making its way under the extension and effectively heating the floor. I have installed a couple of roof ventilators but this did not seem to make any difference. During the build I know the builder did use a lot of insulation and there is very little space for any air flow to come from the old roof into the space between the floors, as this definitely seems to be happening I have been considering that I might need to add some ventilation to the gap between the downstairs ceiling and the upstairs floor to allow some air flow, there was no provision for any ventilation installed to this area. Any recommendation you can make will be greatly appreciated as the new upstairs bedrooms get so hot at night we have found we have to sleep downstairs on the couch, kind of defeats the purpose.

Upper level rooms will always be warmer than the lower storey in hot weather, particularly if they are in or adjacent to the roof space. However, it's unusual for the heat to come from the floor. More commonly the heat load is from the roof and external walls. It should be possible to cut off any air flow from the old roof space into the floor cavity. In our opinion this would be a better strategy than ventilating the floor cavity to the outside air, because on a very hot day ventilation would simply allow more hot air into the building envelope. It's difficult to comment in more detail without seeing your house first-hand. Maybe this is a case where Archicentre could give you some professional advice. They have a website at

Q. We would like to use a real dead tree as a design feature for an interior fit-out and wanted to investigate if this was possible? Are there ways to preserve it so it doesn't deteriorate? Any help would be appreciated, many thanks!

No problem using a dead tree in an interior fit-out. It won't need any preservation as trees only deteriorate if they are eaten away by insects such as termites and/or if they rot away. Dead trees can stand for quite a long time in the landscape but eventually they fall over and then they begin to break down when insects and wood-rotting fungi get busy, helped along by moisture. In a dry indoor environment neither of these hazards (termites or wood rot) will be an issue, but there could be a little bit of borer attack and some fine dust, depending on the type of tree. Also the bark might fall off, or if the tree has been dead for some time the bark might have already gone. There is no practical way to stop the bark coming away once the wood dries out. The tree will also need careful handling to install it, as the smaller twigs and branches will be quite brittle. The effect won't be the same if the branches break off and you are just left with the trunk!

Q. I am trying to buy some Jarrah Veneer Leaf for an artwork. I'm hoping you can help me, I need about 2 square mtrs. I live in the Pilbara area of Western Australia, we don’t have any suppliers here.

All we can suggest is to contact a veneer supplier in WA and see if they can make up a parcel for you - we assume you can receive mail in your area. You will find contact details for veneer suppliers on the Timber Veneer Association's website at Click on the tab that says "How to Find Us". It would be helpful if you can tell them the smallest piece that you can work with. Obviously it would not be practical to mail you a single sheet that is 2m x 2m, but presumably you will be using relatively small pieces for your artwork.

Q. Just wondering what the weight would be per sqm for radiata pine at 60mm thickness?

Like all timbers radiata pine varies in density, with New Zealand-grown timber lighter in weight on average. Australian Standard AS 1720.2-2006, "Timber Structures, Part 2: Timber Properties" gives a figure of 550 kg/m³ as the design density for Australian-grown radiata pine. Using this figure, timber 60 mm thick would weigh 550 x 0.06 = 33 kg/m².

Q. I am trying to lift flooring on a house we are renovating. It is mdf with a veneer or laminate cover. It is difficult to get off our nice timber floorboards trapped underneath this stuff that has been nailed and glued down. We are now pouring hot water on it to see if that will help. Any tips?

It's a pity they nailed AND glued because if the glue has achieved a strong bond there's a risk that the surface of the floorboards will be damaged when you pull the MDF off, so proceed gently. This is a bit outside our field of expertise, but heat could help, depending what sort of glue it is. You could try hot water as a means of softening the glue, but you don't want to saturate the boards underneath. A heat gun might be better, if the heat will penetrate through the MDF, as this would avoid water damage. You might also see whether one of the adhesive companies has some advice. For example, Selleys have a customer help line on 1300 555 205.

Q. I have a warehouse that I want to demo the fire marshal told me that the timbers in there are worth some money. 90000 sq. warehouse with maybe 400 to 500 18ft timbers.

Old timbers are often valuable on account of their large size relative to what is available today. In some cases it's also better quality and of course it will be nice and dry. If you are looking to market the timbers in the US you can find some commercial buyers by searching "reclaimed wood" or "reclaimed lumber" on the net.

Q. Do you know of any Sydney or NSW based importer of Brazilian timber?

Your best source for this information would be the Australian Timber Importers' Federation (ATIF). They have a website at where you will find contact details by clicking on the "Contact Us" tab.

Q. 4 types of non fired bricks and the characteristics of each type and why they are mainly used?

You've contacted a timber advisory service and I'm afraid we don't have any specialised knowledge about bricks. It would be best to address your question to the Clay Brick & Paver Institute. They have a website at

Q. I was just wondering whether and where it is possible to source large pieces of bark, as in a large cylindrical sheet, similar to that of a traditional bark canoe. Should I speak to a veneer manufacturer?

Obviously not all kinds of bark are suitable for making a canoe. The bark of the stringybark tree (Eucalyptus obliqua) seems to have been favoured in Australia although other kinds of bark were used in other countries, depending on what was locally available. There is a good explanation of the process in the Sydney Morning Herald of August 2010 - refer this link I'm afraid we don't know of a source of bark, although it might be possible to obtain some from a country sawmill that processes stringybark logs.

Q. I hoping someone will be able to advise me on the best way to remove glue from timber stairs. The treads were covered in vinyl and the glue residue has remained when the tiles were removed. I'm hoping to polish the treads when all the glue has been removed. The glue would be about 40 years old.

Mineral turpentine should do the job as long as you don't have the old black asphaltic adhesive. The latter is likely to be dissolved by turps but then soak into the wood leaving a black stain. There is quite a lot of good information on the net, logged by people who have tried various methods of removing glue, so we won't bother repeating all that they have to say here. As a starting point, log onto this website


Did you know?

Australia’s 1.9 million hectares of timber plantations produce about two-thirds of the timber products consumed by Australians each year.