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Joinery, cabinetwork & furniture

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. I need some help with a problem - moisture in wood in an antique wardrobe that no matter what we do - e.g. tried vinegar, then soak in bleach, dry with hair dryer, etc. The moisture patch keeps coming back. The moisture also went into a cardboard shoe box and there is no way to dry it out - it keeps coming back even after leaving it in the sun on a 40 degree day for 6 hours? Can anyone enlighten me?

It seems unlikely that your problem is moisture in the wood. Once wood dries out thoroughly it stays dry, unless there is a source of moisture nearby from which it can take up moisture again. Wood doesn't produce moisture from within itself. Is there any condensation in the room where the wardrobe is located? Could it be an oily patch, perhaps from a previous finish that was applied to the wardrobe? An oil or wax coating might look as if it goes away when heat is applied, but it won't evaporate like moisture, and could re-appear if more comes to the surface when the heat is withdrawn. If none of these suggestions seem right, then you've got us stumped! Perhaps a furniture restorer could have a look and give you a definite answer.

Q. We are looking at using spotted gum timber dowels in a house project in Sydney. The dowels are proposed to be 75mm dia x 3m high in spotted gum. Could you please how this may be achieved i.e. in solid or laminated form. Does the spotted gum warp/bend in laminated form? Could you please contact me to discuss.

It should be possible for a local wood turner to produce 75mm diameter round sections. You can find wood turners on the net, or perhaps through the Sydney Woodturners' Guild. Seasoned timber is preferred as it is dimensionally stable and provides a better finish. If you are unable to obtain seasoned spotted gum in the required size, laminating is certainly an option. Glue-laminated spotted gum will be just as stable as the solid material - more so if anything, since any irregularities in grain direction or strength are randomised in the laminating process.

Q. Jarrah is too dark and red for this design. What would you say are other high durability, reasonably-priced timber options for this application (window joinery), that are lighter in colour - closer to Rosewood?

It's always possible to have your window joinery purpose-made, in which case you can nominate any available type of timber. Joinery companies that specialise in architectural work could advise you further. You could consider timbers such as merbau, which is in the lighter brown colour range. However, it's likely to be more economical to select from a range of standard windows such as those offered by Trend, Stegbar, etc. In that case you are limited by the company's preferred timber species.

Q. We're planning on building a new home, and would like to have natural (unpainted) timber window frames. We're happy to use preservatives and oils, but not paint or urethane. Some of the frames would receive direct sun and weather. We're not in a high fire risk area. We'd prefer FSC/ responsibly sourced. I'm concerned about durability and cost. I've found a local supplier who uses Rosewood which is Class 1 durability, but it's on the expensive side. Western Red Cedar is Class 2 durability, but a bit soft. Do you have recommendations for other types of timber to look into? We live in Melbourne.

Western red cedar is fairly soft but generally performs well if it's out of range of knocks and bumps. Hardwoods suitable for window joinery are in the higher price range because they are selected to be of high quality, free of knots and other blemishes. You could consider jarrah from Western Australia (as distinct from "Pacific jarrah" which is actually a South American timber). Jarrah windows are durable and hard-wearing. If you are planning to oil them, be aware that the windows under full weather exposure will need oiling several times a year to look their best. We also recommend that the glass is installed with wooden glazing beads bedded in silicone, rather than putty, since putty needs the protection of paint to prevent it drying out and cracking in the long term.

Q. I wanted to enquire as to the best timber to use for a north facing solid timber door (with NO headlight and NO sidelights)? I was thinking of Jarrah or Teak. I assumed that since Teak is the best for outdoor furniture, it would perform well for an entrance door as well. Other options recommended are Western Red Cedar, Merbau & Rosewood. Please advise the relative merits of each, particularly in terms of strength and weather (sun/rain) resistance. Thank you.

If the door is exposed to rain regularly, without any porch, canopy or verandah, we suggest western red cedar, since it is one of the most dimensionally stable of the timbers you mention. Teak also has excellent weathering qualities but you are probably not going to purchase a teak door off the shelf, whereas western red cedar doors are more readily available, eg. the Trend range, the Wideline range, etc. You can find these, and others, on the net. Cedar is a relatively soft timber, but will stand up to normal wear (no dogs scratching to get in, children kicking it, etc.) In addition to choosing a suitable timber, it's important to apply a suitable UV-resistant finish. Make sure all edges are sealed, top, bottom and sides, as well as the front and back of the door.

Q. Where can I purchase various timber varieties adhesive strips 1.5 metres long by 18mm wide?

Consolidated Veneers have a range of iron-on edge strips. You can find out more about their use and application at this address:

Q. We are looking for some specialist advice regarding timber species for use in joinery: We are looking at something that looks similar in colour to: American White Oak but is locally sourced (i.e. QLD grown and local species) And is compatible with a very fine-scale of timber routing artwork. Would either of these species be workable? Can you suggest others? White Mountain Ash/ Tasmanian Oak Kauri, Queensland | Agathis robusta Hoop Pine- QLD

Mountain ash/Tasmanian oak does not grow in Queensland, but kauri and hoop pine are suitable for specialist joinery. Kauri would be the preferred species in our opinion, and in earlier times it was used for pattern-making since it holds its shape well. But to be sure it suits your needs we suggest you ask a supplier for some samples.

Q. I am doing some research for a potential project that would require a large amount of custom timber joinery in SA. In particular we are looking for any information on vertically laminated benches and the possibility of introducing recycled timber into the equation. Additionally I am looking for information on selecting sustainable timber sources to SA. I know this is pretty vague but any help would be appreciated.

In South Australia there are several companies that recycle timber, the major ones being Adelaide & Rural Salvage at Wingfield, and Adelaide Recycled Timbers at Uraidla. There are no specific issues that apply to using recycled timber for laminated benchtops and joinery - the same techniques apply as for new timber except, of course, the need to watch out for embedded fasteners and other foreign bodies. With regard to benchtops, correct installation is important and you will find some useful guides on the net, eg. the one published by Dale Glass Industries at this address:

Q. I am in research of a timber screening product which is similar to supa slat maxi beam for a hospital reception as division. Can someone please suggest a few alternative products?

We don't know of anyone producing a product similar to Supaslat Maxi as a standard item, but it would be possible to have a joinery shop make slats from materials of your choice, which a carpenter could then install on site. We understand Supaslat is medium density fibreboard (MDF) with a timber veneer on the surface. So your choice is to specify slats similar to the Supaslat, or alternatively slats of solid timber. The latter might be a better choice if in a situation where they will be exposed to wear and tear.

Q. I have a client that is wanting to use meranti externally as door frames on his house, I have told him it is not durable enough for external use and doesn't meet the standard for external use. I can't seem to find any documentation that states that class 4 timber is not allowed for external use can you advise me where I might get this to provide him with the documentation. We are based in Coffs Harbour New South Wales.

Meranti would be suitable for external door frames if the doors were set back under a verandah or canopy, but in our view it's not the best choice for full weather exposure unless preservative treated by the LOSP process. Some joinery manufacturers treat their meranti window frames in this way. However, as far as we are aware there's no regulation that says untreated Class 4 timber is not allowed for external door frames. The Building Code of Australia (BCA) is mainly concerned with structural materials and doesn't cover door frames. Perhaps reference to Australian Standard 5604 "Timber - Natural durability ratings" might persuade your client. AS 5604 quotes a "probable life expectancy" for Class 4 timbers of up to 7 years in above-ground situations fully exposed to the weather.


Did you know?

Logs from plantations cannot produce the sawn hardwood timber produced from logs currently harvested from native forests.