Characteristics

Pacific HemFir Characteristics and Properties

​​Pacific HemFir is a combination of two of British Columbia’s most abundant species, Western hemlock (Tsuga heterophylla) and Amabilis fir (Abies amabilis). Growing intermixed, these high-value species are virtually identical in appearance and share many performance characteristics.

Both species have a fine texture and a straight, uniform grain. Air and kiln drying are used to season Pacific HemFir. Once dry, the wood is stable and has excellent wearing qualities. Pacific HemFir’s dominant characteristics are its strength, stiffness, density, durability, and colour. Its high bending strength (MOE) and stiffness (MOR), make it an excellent choice for applications where strength and bending are required, such as  long spans and load bearing applications.

Based on an in-grade testing program conducted by Timber Engineering and Applied Mechanics at the University of British Columbia, a code change proposal was prepared and accepted by the CSA 086 Technical Committee on Engineering Design in Wood, the Canadian Standard.

CSA 086:19 published new specified bending strength properties of HemFir (N) Beams and Stringers grades. Significant increases in the specified bending strength fb of HemFir (N) ranged from 14% for the select structural grade to 53% in the No.2 grade.

The increased specified bending strength properties of HemFir (N) beams and stringers grades opens up opportunities in selection for designers and expands the structural applications of HemFir (N) material in heavy timber construction.

The species’ higher density also makes it ideal for applications that use fasteners and metal connectors.

Pacific HemFir lumber physical attributes include: 

High strength, stiffness and density—it is ideal for most structural and industrial uses from framing lumber to heavy timbers to engineered components. 

High density provides superior nail and screw holding properties—lending it to applications that use fasteners and metal connectors. 

Easily pressure treated—improving durability and making it a preferred choice where preservative-treated wood is required. 

Good compression—parallel to grain and perpendicular to grain. 

Clear and Shop grades that are ideal for many appearance and joinery applications—such as paneling, furniture, windows and doors. 

Excellent for finishing and staining—because of its uniform natural color (almost white) and freedom of pitch, it finishes extremely well with stains and paints, making it highly suitable for moldings and millwork.

Excellent machining properties—and a fine, straight grain.

Comparative Physical Properties of Pacific HemFir

			HEMFIR
	HIGH RANGE ◆	LOW RANGE ⚈	AMABILIS FIR	WESTERN HEMLOCK
Physical Properties
Density (12%-kg/m3 )			445	480
Specific Gravity (12% m.c.)			0.39	0.43
Bending Strength (MOR)(MPa)			68.9	81.1
Stiffness (MOE)(x103MPa)			11.4	12.3
Compression parallel to grain (MPa)			40.8	46.7
Compression perpendicular to grain (MPa)			3.6	4.5
Shear (MPa)			7.5	6.5
Cleavage (N/mm)			36.8	37.5
Dimensional stability			9.2	7.8
(Shrinkage % green to O.D.)			4.4	4.2
Hardness (N)			1820	2740
Durability
Natural durability (approx. life in contact with ground)	>10 yrs	≤ 10 yrs	⚈	⚈
Treatability (preservatives or fire)	permeable – moderately resistant	resistant – extremely resistant	◆	◆
Drying
Drying rate	rapid – moderate	fairly slow – very slow	◆	◆
Tendency to check during drying	absent or easily controllable	controllable with some care	◆	◆
Tendency to distortion during drying	absent – slight	moderate	◆	⚈
Workability
Machining (planing/turning/moulding/ mortising/boring, etc.)	good – excellent	fair	◆	◆
Blunting	very little/slight – little/slight	moderate	◆	◆
Nailing/resistance to splitting	well – excellent	poor – satisfactory	◆	◆
Screw/nail holding	good – excellent	satisfactory	◆	◆
Gluing	w/out difficulty – exceptional	difficult – satisfactory	◆	◆
Finishing
Natural colour: whitsh1, lt. buff2, yellwsh-brn3			1,2,3	1,3
Paint finishing	good – excellent	poor – satisfactory	◆	◆
Stain finishing	good – excellent	poor – satisfactory	◆	◆
Tendency to resin exudation	absent or infrequent after drying	depends on finish used & visual standards	◆	◆
Miscellaneous Properties
Tendency to corrode ferrous metals	likely	unlikely	⚈	⚈
Becomes stained in contact with ferrous metals	likely	unlikely	⚈	⚈

Pacific HemFir is Also Available Sorted

Although Pacific HemFir is harvested and manufactured as mixed-species group (approximately 80% Western hemlock and 20% Amabilis fir), and the NGLA grades are based on this mix, the individual species are also available sorted to take advantage of Amabilis fir’s quicker drying time and better suitability for exterior applications like decking.