Project Description

WOOF Timber - Grey Box

Grey Box

Other Names

Gum-topped Box, Eucalyptus Microcarpa, Eucalyptus Woollsiana, Eucalyptus Hemiphloia

Grey box is a highly durable Australian hardwood often used for heavy construction applications and flooring.

Grey box is a tough, highly durable medium-sized Australian hardwood. It originates from the central and north coast districts of New South Wales and southern Queensland. Grey box, Eucalyptus woollsiana also occurs in parts of Victoria and South Australia.

Its heartwood is a pale, yellowish brown with the sapwood paler in appearance. It has a fine, even texture and usually features an interlocked grain. Gum veins are rarely present.

Grey box is a highly dense species, so it is quite difficult to work. It can be painted, stained and polished. Any machining or surface preparation should be done immediately prior to gluing. It is slow to dry but generally will not develop any surface checking.

Grey box is used for heavy construction, flooring, round timber wharfage, sleepers and shipbuilding.

It is mainly available in the areas in which it grows.

Shrinkage

Very Low Low Medium High Very High
Tangential 7.40%
Radial  3.30%
Unit Movement Tangential  0.43%
Unit Movement Radial  0.23%

Strength Group

Very High High Reasonably High Medium High Medium Reasonably Low Low Very Low
Unseasoned S1 S2 S3 S4 S5 S6 S7
Seasoned SD1 SD2 SD3 SD4 SD5 SD6 SD7 SD8

Stress Grade

Structural No. 1 Structural No. 2 Structural No. 3 Structural No. 4 Structural No. 5
Unseasoned F27 F17 F14 F11 F8
Seasoned F34 F27 F22 F17 F14

Density per Standard

Seasoned 1105kg/m3
Unseasoned 1230kg/m3

Joint Group

Very High High Reasonably High Medium Low Very Low
Unseasoned J1 J2 J3 J4 J5 J6
Seasoned JD1 JD2 JD3 JD4 JD5 JD6

Colour

White, yellow, pale straw to light brown Pink to pink brown Light to dark red Brown, chocolate, mottled or streaky

Mechanical Properties

Modulus of Rupture – Unseasoned 98
Modulus of Rupture – Seasoned 143
Modulus of Elasticity – Unseasoned 13
Modulus of Elasticity – Seasoned 16
Maximum Crushing Strength – Unseasoned 50
Maximum Crushing Strength – Seasoned 78
Impact – Unseasoned 19
Impact – Seasoned 15
Toughness – Unseasoned
Toughness – Seasoned
Hardness – Unseasoned 11
Hardness – Seasoned 15

Durability

Low Moderate Reasonably High High
(0 – 5 yrs) (5 – 15 yrs) (15 – 25 yrs) (more than 25 yrs)
In-Ground
(0 – 7 yrs) (7 – 15 yrs) (15 – 40 yrs) (more than 40 yrs)
Above Ground
(0 – 20 yrs, usually < 5) (21 – 40 yrs) (41 – 64 yrs) (more than 60 yrs)
Marine Borer Resistance
Lyctid Borer Susceptibilitiy Susceptible
Lyctid Borer Susceptibility – Other
Termite Resistance Resistant

Fire Properties

Critical Radiance Flux – Lower 2.2 and < 4.5
Critical Radiance Flux – Higher ≥ 4.5
Smoke Development Rate < 750
Average Specific Extinction Area < 250
Bushfire Resistance BAL 12.5 and 19 – All AS3959 required applications
Botanical Name Eucalyptus moluccana
Preferred Common Name Grey Box
Species Type Hardwood

Appearance

Grey box has heartwood that is a pale, yellowish brown with the sapwood paler in appearance. It has a fine, even texture and usually features an interlocked grain. Gum veins are rarely present.

Grey box is very similar in appearance to coast grey box.

Common Applications

Tough and highly durable, grey box is mainly used for heavy engineering construction and flooring.

It is also used for cladding, bridges, wharves, shipbuilding, piles, poles and sleepers. Grey box is also an excellent fuel wood.

Common Form

Sawn

Workability

Grey box is a highly dense species so it is quite difficult to work. It can be painted, stained and polished. Any machining or surface preparation should be done immediately prior to gluing. It is slow to dry but generally will not develop any surface checking.

Origin of Timber

NSW

Readily Available

NSW

Availability – Further Information

Grey box is mainly available around the areas in which it grows. It is primarily available as flooring and construction material. Check with local suppliers for further information.

Native Forest.

Structural Timber Poles

Timber pole construction is typically utilised to provide support for gravity loads and resistance against lateral forces. The natural appeal of timber ensures that its role is not purely structural however, with timber poles complimenting architectural designs aimed at harmonisation with the natural environment. The small number of footings required in pole frame construction also ensures minimal disturbances to the site.

With a double bearer system, poles can be spaced further apart than is usual, creating a more spacious building interior, that allows greater interior design flexibility. While poles are usually placed in a grid like system this is not compulsory and the flexibility of the application means the system can cope with a wide variety of designs, enabling designers to take full advantage of beautiful outlooks.

This article provides a comprehensive overview of the process involved in specifying, designing and constructing a solid timber pole construction.

Flooring

Whether for structural or finished flooring applications, timber offers durability, versatility and adaptability. The warmth, strength and natural beauty of timber flooring has proved enduringly popular in a wide variety of interior settings.

Timber flooring is a timeless product, offering a warmth and natural beauty largely unmatched by other flooring options. This article provides an overview of the installation of solid timber strip flooring over bearers and joists, timber based sheet flooring products and concrete slabs. Timber flooring is typically supplied as either solid timber or laminated wood products, made from layers of bonded timber. It fits together with a tongue and groove joint and once in place, is sanded and finished. There is a wide variety of species to select flooring from and the right species for a given application will be dependent on numerous factors. Information relating to species selection, environmental assessment, finish selection and recommended maintenance routines are all provided in this section.