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Spruce-Pine-Fir (SPF)
Spruce-Pine-Fir, or SPF, is the generic name for a variety of softwood species, even-grained and yellowish-white in colour, imported from North America and used in housing construction frames.

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Grey Gum | Eucalyptus propinqua

Grey Gum is an Australian hardwood timber ranging in colour from red to reddish brown.

Grey Gum is a native Australian hardwood timber with extreme hardness and durability, making it suitable for a wide range of engineering and general construction applications, from mining timbers to flooring and decking.

Grey Gum is an extremely hard and durable native Australian hardwood timber, suitable for a wide range of engineering and construction applications.

Other Names: Grey Iron Gum, Eucalyptus punctata, Large-fruited Grey Gum, Small-fruited Grey Gum, Eucalyptus canaliculata, Eucalyptus major, Brown Grey Gum,

Overview
Properties
Description
Applications
Suppliers

Overview

Grey Gum is a medium-sized hardwood tree growing up to 40 metres in height and one metre in stem diameter. Varieties of Grey Gum occur along the east coast of Australia, from the Hawkesbury River in New South Wales as far north as Maryborough, and inland to the Carnarvon Ranges and Blackdown Tablelands in Queensland.

The heartwood of this species is a red to reddish-brown colour, visually distinct from the paler sapwood. Grain is usually interlocked, with a coarse but even texture. Grey Gum is similar in general appearance to the ironbarks, but often marked by characteristic grub holes.

Grey Gum timber is an extremely durable timber, with an in-ground life expectancy in excess of 25 years. For aboveground applications, life expectancy exceeds 40 years. Grey Gum heartwood is termite-resistant, and untreated sapwood is not susceptible to Lyctid borer attack. Grey Gum sapwood is readily impregnated with commercially available preservatives.

The timber is very hard, rated 1 on a 6-class scale in relation to both indentation and ease of working with hand tools. It machines well, although care is required in working the timber’s interlocked grain. Grey Gum readily accepts paint, stain and polish, and is amenable to the use of standard fastenings and fittings. As with most high-density species, machining and surface preparation should be done immediately prior to the application of adhesives.

Grey Gum is widely used in heavy engineering and marine construction, where it is found as poles, piles, railway sleepers, cross-arms and mining timbers. In general construction it is used for building framework, flooring and decking. Grey Gum is also extensively used in landscaping and boat building. It is renowned for making superior-quality butcher’s blocks suitable for use in both commercial and domestic environments.

Properties

Shrinkage

	Very Low	Low	Medium	High	Very High
Tangential:
Tangential:				7.0
Radial:				4 - 5

Strength Group

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

Stress Grade

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

Density per Standard

Unseasoned:	1240 kg/m³
Seasoned:	1060 kg/m³

Joint Group

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

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:	110
Modulus of Rupture - Seasoned:	140
Modulus of Elasticity - Unseasoned:	16
Modulus of Elasticity - Seasoned:	18
Maximum Crushing Strength - Unseasoned:	51
Maximum Crushing Strength - Seasoned:	72
Impact - Unseasoned:	19
Impact - Seasoned:	21
Toughness - Unseasoned:	Medium - 15 - 25 Nm
Toughness - Seasoned:	Medium - 15 - 25 Nm
Hardness - Unseasoned:	10
Hardness - Seasoned:	14

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 Susceptibility:	Not Susceptible
Termite Resistance:	Resistant

Fire Properties

	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
EFH Ignitibility:

	0	1	2	3	4	5	6	7	8	9	10
EFH Spread-of-Flame Index:
EFH Smoke-Developed Index:

	1 - non-combustible	2 - reasonably non-combustible	3 - slightly combustible	4 - combustible
Fire Properties Group Number:

Group Number - Other:	3 if used on MDF or particleboard ≥12mm; veneer thickness 0.6-0.85mm
Average Specific Extinction Area:	<250
Bushfire Resistance:	BAL 12.5 and 19 – All AS3959 required applications

Description

Botanical Name:	Eucalyptus propinqua
Preferred Common Name:	Grey Gum
Other Names:	Grey Iron Gum, Eucalyptus punctata, Large-fruited Grey Gum, Small-fruited Grey Gum, Eucalyptus canaliculata, Eucalyptus major, Brown Grey Gum,
Species Type:	Hardwood

Appearance

The heartwood of this species is a red to red-brown colour, visually distinct from the paler sapwood. Grain is usually interlocked with a coarse but even texture. Grub holes are an occasional feature in sawn timber products.

Common Applications

Common Form

Sawn

Workability

Because of its density and grain structure, Grey Gum is difficult to work when dry. It machines satisfactorily, although care is required in working the timber’s interlocked grain. Grey Gum readily accepts paint, stain and polish, and is amenable to the use of standard fastenings and fittings. As with most high-density species, machining and surface preparation should be done immediately prior to the application of bonding agents.

Origin of Timber

NSW, QLD

Readily Available

NSW, QLD

Availability - Further Information

Grey Gum timber products are readily available in New South Wales and Queensland.

Source of Timber

Native Forest

Applications

Decking

Timber decking creates spaces that are functional, practical and aesthetically pleasing. With the right design and care a timber deck will make a valuable addition to any home or business, creating an outdoor living space that will be enjoyed for years to come.
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.
Framing

Since people began building simple shelters, wooden framing has played an important role in shaping structures of many kinds. One of the most popular types of wooden framing is known as lightweight timber construction.
Retaining Walls (Landscaping)

When it comes to retaining wall, landscape design and construction, timber is the natural choice. A material that is durable, sturdy and reliable, it boasts natural aesthetics that help it blend seamlessly with the outdoors. Careful consideration during the specification and design process will facilitate the creation of a long lasting, durable and eye catching timber retaining wall that will complement its surrounding landscape for years to come.
Structural Timber Poles

Timber poles are utilised in structural construction to provide support for gravity loads and resistance against lateral forces. Not only serving a structural function, timber poles provide many aesthetic benefits, with their use in construction often complementing architectural designs aimed at harmonisation with the natural environment.
Timber Portal Frames

For buildings that require large spans and column free interiors, timber portal frames provide one of the most aesthetically pleasing solutions. Utilising modern engineering technology, portal frame design transforms timber into a highly effective, efficient and economical structural product. This application guide provides a comprehensive overview of the process of using timber in the specification, fabrication and erection of portal frame structures.