FRAME AND TRUSS COMPONENTS
The ‘Frame & Truss’ industry has for many years been under extreme competitive pressure. Every fabricator is constantly seeking to increase their efficiency and reduce cost to remain competitive.
Apart form the ongoing labour management issues, new and better ways have to be implemented to remain ahead of the game. Equipment and technology improvements have to always be considered to gain that edge however ways in materials cost reduction and utilisation will also boost competitiveness. Optimising inventory purchasing will always gain results before optimising purchased inventory.
What is purchased is so important to installed unit cost. The classic tell tale is if a plant recovers enough trimmers, nogs & blocks from offcuts of chords, studs & plates – the purchasing process needs review. In fact the more requirement to buy in blocking products is an indication of stronger purchasing efficiency.
As the Frame & Truss industry has generally recognised this type and other similarly important cost savings in inventory management, so PTS has been able to provide plants with true advantages. Block, web and stud products processed by PTS have been used throughout the eastern seaboard to give plant operators a distinct opportunity in reducing unit cost.
Truss Plant Cutting Capacity
PTS group a whole range non-structural frame & truss components to call them ‘blocks’. These include noggins, trimmers, sprockets, junction blocks, outriggers, etc.
Block Sizes: 67×35, 70×35, 87×35, 90×35, 67×45, 70×45, 87×45, 90×45.
Millions upon millions of these components have been precision docked by PTS and are supplied in a range of formats. As a general rule a block product is around 20% below the cost of MGP10 material. Therefore when considering many blocks used in plants have been ‘recovered’ from MGP10, a cost disparity immediately emerges.
PTS produces blocks in either untreated or H2-F (Blue Pine). Blue blocks are individually branded for compliance purposes and for product tracking. Many standard size and length combinations are held in stock though specific blocks are easily ordered and supplied.
A popular service PTS offer is the bundling of blocks especially useful when ceiling trimmers are sent to site as ancillary products. Bundle sizes are small enough to be easily moved single handedly.
Custom packs sizes are also able to made to suit various plant storage restrictions. A slightly longer lead time may be experienced.
Undersize blocks (eg 65×30, 87×35 etc) are also offered to ensure non-protrusion or other specific needs. An additional small cost is incurred for re-sizing. As PTS H2-F (Blue Pine) is the last part of the process, these undersize Blue blocks are treated all round.
PTS are major producers of roof truss webs. All product is graded at the St Marys operation to ensure grade certainty. All truss web product is graded to a F7 standard. As this is the highest grade PTS produce, it naturally occurs that material capable of being a higher grade is included. This has allowed for a high regard of the PTS output. Typically in other mill and production centres their chase for highest possible grade yield means their F grade products will be to grade but won’t exceed next grade thresholds.
Webs are available in untreated and H2-F (Blue Pine). Blue webs are individually branded for compliance purposes and for product tracking.
PTS produce over 140 different web products. This large range is entirely in F7 grade and is made up of 70×35 and 90×35 dimension. Square end webs are available from 300mm to 2250mm in 150mm increments. Turb-O-Webs are available from 300mm to 3000mm in 150mm increments. Turb-O-Webs are also available in 70×35 & 90×35 dimensions.
Product is held consistently across the range to ensure our customers’ plants have stock in all lengths available. Custom packs sizes are also able to made to suit various plant storage restrictions. A slightly longer lead time may be experienced.
Wall studs are produced through the PTS plant. All product is graded at the St Marys operation to ensure grade certainty.
70×35 F5 and F7
70×45 MGP10 (mill graded)
As PTS produce F7 as our highest grade, it will include higher grade material. Typically F grade supply from other producers won’t have this better product included as it is usually pulled out and sold as higher grade at higher prices.
Wall studs are available in untreated and H2-F (Blue Pine). Blue studs are individually branded for compliance purposes and for product tracking.
Studs are available in standard 300mm increments or ‘docked to length’ to customer’s specification. Customers appreciate the ability to order their special lengths which other large producers have difficulty in supplying. Not only can PTS supply but does so on short lead time.
TIMBER STRUCTURAL GRADING
When specifying timber for use in a structural application certain design properties must be known so the correct dimension and stress grade is used.
A structural timber stress grade is made up of a number of different design characteristics which includes bending strength, bending stiffness, compression strength, tensile strength, shear strength etc. Each timber stress grade has a set minimum value for each of these criteria. For a piece of timber to have a stress grade all of the minimum criteria for that grade need to be met.
One or more of these criteria will be relevant and which ones are dependant on the application. For example a truss chord will primarily be designed or specified in relation to bending stiffness (to ensure a deflection limit is not exceeded), a wall stud is primarily designed with consideration of compression parallel to grain.
The Australian Standard AS 1720.1 contains the individual characteristic values for design relevant for both ‘MGP’ and ‘F’ stress grades. All producers need to ensure whatever stress grade they stamp their timber will meet at least the minimum requirement for all characteristics of that grade. There are several production methods producers can use to show they have an adequate grading process in place. These methods for solid softwood are covered in standards AS/NZS 1748, AS 2858 or AS 3519.
On top of all of that the grading result needs verification testing with most producers using the standard AS/NZS 4490 for that purpose and AS/NZS 4063 for method.
Basically if you are going to produce or sell structural timber in Australia you need to be doing it right.
The conversion in the 1990’s to ‘MGP’ grades by the major Australian softwood producers had a number of advantages for them. Although there was no issue either technically or structurally with the ‘F’ grade system some of the individual design characteristics were seen as ‘light on’ when compared with others. It was felt better utilisation of product could be achieved with a realignment of the characteristics. It was a view of ‘let’s use the full structural potential of the fibre rather than being too conservative’.
In this process it was important that more was known about the characteristics and their relativity to each other. Considerable testing of timber from various locations was done to establish correlation between characteristics. Correlations and averages were determined according to forest location and tree growth. Each area had its own values.
Programmed Timber Supplies sources feedstock from a number of locations which makes it difficult to implement a ’MGP’ type grade system but alternatively rely on the actual properties of each component. Additionally Programmed Timber Supplies manufacture ‘components’ so they know the end application and what are the relevant attributes that make each component truly ‘fit-for-purpose’. This is a manufacturing advantage over a sawmill that never knows what will be the specific application for each segment of each board.
The ‘F’ grade system used by Programmed Timber Supplies is supported by their ability to design in the actual requirements of each and every one of the 25 million components they currently process each year. The use of high speed scanning technology permits this product certainty and also allows inclusion of such attributes as end zone grading (for nail plate or end grain nailing application), nominated point load specification, non defect board density for joint strength certainty etc.
Especially for wall frame and roof truss fabricators the buying in of grade certain common components from Programmed Timber Supplies allows for greater plant output by allowing them to only concentrate on cutting the job critical components.