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Interior timber & flooring

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. Can we have sample of timber wall panelling : Box, Brush | Lophostemon confertus The application is for internal wall panelling. Should I spec laminated veneer lumber or medium density fibreboard?

If you are considering solid timber panelling it's not necessary to install it over laminated veneer lumber (LVL) or MDF. Boral has a range of solid hardwood claddings that can be used indoors or outdoors, fixed directly to timber framing or battens. However, if you are considering brush box veneer then it would have to be laid up onto medium density fibreboard or particleboard. We don't have samples or timber for sale, but a timber merchant in your area should be able to provide samples.

Q. Our proposed ground floor living room has a large expanse of north-facing glass doors leading on to the alfresco. The alfresco has a retractable roof, in winter we would probably want to leave it open to allow light & warmth into the house. However, this means that sun will be hitting the floorboards. So, our dilemma: do we install blinds to keep the sun off the floorboards? Should we use a different product (tiles) for that section of the floor that will get the sun in winter?

Difficult to give you a definite answer, since it depends how hot the winter sun is likely to be. No doubt it won't be as hot as summer sun and presumably won't shine every day, nor for such a long part of the day. We are inclined to think it won't be a problem, and that the floorboards will tolerate some winter sun. Make sure the flooring is dried to a suitable moisture content at the time of installation, and allow a period of acclimatisation if necessary. The flooring supplier and/or installer should have a moisture meter to test the timber and if you are located in the southern States the recommended moisture content would be around 10% - slightly higher if you in a tropical region. For further information, our Technical Design Guide no. 9 would be helpful. It can be downloaded via this link:

Q. I am an architect working on a heritage building. We have uncovered some Kauri timber ceiling panelling. We are removing this timber, and I want to know if this timber would be appropriate for re-use as floor boards. Your advice/assistance would be greatly appreciated.

Kauri pine was used for flooring in the past, when it was more readily available, and it makes an attractive floor. Being a softwood it is less resistant to wear and tear than the denser Australian hardwoods, so its suitability will depend on levels of pedestrian traffic, and particularly whether it will be exposed to stiletto heels. The hardness rating of kauri pine, and therefore its resistance to indentation, is in a similar range to radiata pine. Perhaps there will be rugs or mats in high traffic areas so that the timber is not directly exposed to foot traffic.

Q. I'm looking for some samples of end grain flooring in dark stain, not red toned, and is a solid reclaimed timber flooring. Would I be able to obtain some samples by next Tuesday or Wednesday the latest?

Our website is simply for advice on the use of timber products, we don't provide samples. However, a company called Mafi specialises in ebd-grain flooring and you can visit their website at this address:

Q. We spec Brush Box for residential project. We want to ensure new timber floor at same finish floor level through out on top of 2 different substrates (existing timber floor, new concrete slab). Is there any key specification should I know?

A new concrete slab contains significant moisture so it is important to take this into consideration. If the new brush box flooring is installed on battens a membrane moisture barrier can be installed over the concrete and held in place by the battens. Similarly if the brush box is to be glued to a plywood underlay, a moisture barrier can be installed under the plywood. You might find it helpful to refer to our Design Guide #9 titled "Timber flooring - design guide for installation", available for download at this address:

Q. I'm interested in ply wood panels to install inside a 10m x 16m shed ceiling. Would this be an option that I could consider?

Random grooved plywood is probably the best choice for this application. The longest sheets we are aware of are 3050mm long by 1220mm wide. The side joints are disguised by appearing as another random groove, but there will be an obvious join where the sheets meet end to end. The best strategy is to cover this with a batten or, for a better appearance, by an exposed beam. You will find suppliers if you write "random grooved plywood" in your browser.

Q. We have 80 yr plus old buildings with old shotedge hardwood floors and gaps of up to 1/2". Would you please advise how to treat the gaps.

We take it that the term "shotedge" refers to boards that are square edged rather than tongued and grooved. Gaps that size suggest that the floors were laid with unseasoned hardwood, since presumably the boards were butted together when laid but shrank as they dried. It will be difficult to fill the gaps satisfactorily since a filler would work loose as the boards flex under foot and will fall out. The only way to fill the gaps would be insert strips of wood, but this would be a tedious and time-consuming job over a large area. We suggest you accept the gaps as part of the historic character of floors from an era before tongued and grooved boards were common. If the floors allow draughts or insects to enter through the gaps perhaps another way to approach it would be to install lining boards to the underside of the joists, thus sealing the floor from below.

Q. Our dance club venue has had a blackbutt 14mm floor laid on concrete (glued direct) and has cupped only after a few weeks, it has now been down about 2 years and we have been told it needs to be sanded and resealed at a cost of $6500-00. We don't want this expense again. They have used a polyurethane waterbase seal and we would like to know if there is another option for protecting the wood which can be used frequently but doesn't need sanding.

We weren't sure if sanding was needed to remove the cupping, or because the polyurethane seal had worn off (or both). Heavier sanding will be needed to remove cupping, compared with sanding a flat floor to prepare for refinishing. Perhaps you should get a second quote if you feel the cost is a little high. Regarding alternatives to polyurethane, there are finishes that don't require prior sanding, eg. oils and waxes. You will find some leads if you write "best oil for timber floors" in your browser. However, you should also check the maintenance requirement for this type of finish as some need buffing with an electric floor polisher.

Q. I would like to clad an internal wall in a guest pod with timber. The wall runs from a kitchenette into a bathroom past a frameless glass door. The dimension of the area would be 2 by 6 metres. It sits 300mm off the floor and is on the opposite side to the water sources in the bathroom, so will only be exposed to air borne bathroom moisture, no direct splash. There will be an exhaust fan in operation whenever the bathroom is in use. I would like to use 12mm T&G overlay flooring and at this time I am looking at Boral product. The species available are Australian Beech, Blackbutt, Messmate, New England Oak, Stringy Bark, Flooded Gum, Forest Red, Red Mahogany, Sydney Blue Gum, Brush Box, Tallowwood, Ironbark, Turpentine and Spotted Gum. How do I make it work and how do I finish the timber?

Overlay flooring can be used as wall lining, but the boards meet with a butt joint. This is desirable for flooring because it prevents dirt from collecting between boards. Wall linings usually have a v-joint or square joint between boards. This isn't practical on a floor, but such a joint allows minor movement to take place in the width of the boards without being noticeable. Some companies provide lining boards that are pre-finished so you don't need to finish them on site. However, if using raw timber we recommend satin or matt polyurethane which seals the wood against moisture and provides a surface that can be wiped clean.

Q. I have 20 year old Brushbox T&G flooring which I have stored in my attic. The timber is still is great condition however when placed next to recently purchased Brushbox boards, the colour of the older ones is much more yellow. I was looking at combining both lots of boards and was wondering whether the new timber boards will eventually match the older ones in time.

It's hard to know whether the older flooring has changed colour while in storage or whether it was a different colour to start with. Wood does change colour a little with age, but it's also true that the same type of wood from different trees will vary. However, you might find that the colour of the two batches is similar when the floor is sanded. To test this, try sanding a couple of the boards you have been storing. If they changed colour while in the attic, the colour change will be quite shallow and the original colour will soon show through. On the other hand, if they are still yellowish after sanding that would suggest the wood itself is different and is unlikely to ever match the new timber.


Did you know?

A government report showed there is no evidence proving that harvesting timber from native forests has reduced overall forest biodiversity or led to the extinction of any species of plant or animal.