Angle
Knee Portals

Data Sheet

Overview

The TimberLab Angle Knee Portal has become a mark of success, combining the best in appearance with the best in economy.

A factory-made interlocking glued knee joint provides the basis of the three pin or two pin portal design used. The maximum inside height possible at the knee is obtained in this portal – a factor which gives it an advantage over the curved portal in some applications. The build-up of interlocking rafter and column panels means that the column section is wider than the rafter e.g. 3 x 42mm column panels interlock with 2 x 42mm rafter panels. This gives a column width of 5 x 42 = 210mm and a rafter width of 3 x 42 = 126mm. Column and rafter section taper from a maximum depth at the knee to a minimum depth at the base and apex. By increasing the depth of the panels and building up the number of interlocking panels, any practical span and spacing can be catered for.

On smaller spans or farm buildings a double column and single rafter combination can be used.

A simple bolted pin joint at the apex is all that is required to connect the full portal frame together. All apex fitting and base connections are done in TimberLab’s factory and make for easy on-site assembly.

With a sanded and stained finish, these portals enhance the appearance of any community building or with a dressed finish they are an economic winner in industrial buildings. 

Site Assembly – Members arrive on site in the form of half portals. With the use of a mobile scaffold to support the apex, erection is quickly achieved by lifting the half portals into position onto holding-down bolts and aligning the simple bolted apex joint.

An average of 7 to 10 portals can be fully erected in a working day. Each frame can be temporarily braced longitudinally so that a secure structure is available for cladding and roofing. With the convenience of nailing directly to the timber frames no specialist labour is required.

Notching or cutting or drilling the portals must be approved by the TimberLab designer or design engineer.

Indicative Sizes for Angle Knee Portals

Portal Span (m) Frame Spacing Eave Height Light Roof & LL=0.25 kPa Column Ceiling Rafter Heavy Roof & LL=0.25 kPa Column Ceiling Rafter
8 3
4
5
2.5
2.5
2.5
315x149
315x149
315x149
360x65
360x65
360x65
315x174
315x174
360x174
360x90
360x90
405x90
9 3
4
5
2.5
2.5
2.5
315x174
315x174
315x174
360x90
360x90
360x90
315x174
360x174
405x174
360x90
405x90
450x90
10 4
5
6
2.5
2.5
2.5
315x174
315x174
360x174
360x90
360x90
405x90
360x174
405x174
450x174
405x90
450x90
495x90
11 4
5
6
2.5
2.5
2.5
315x174
360x174
405x174
360x90
405x90
450x90
405x174
450x174
450x210
405x90
495x90
540x90
12 4
5
6
3.0
3.0
3.0
360x174
405x174
450x174
405x90
450x90
495x90
450x174
450x210
495x210
495x90
540x126
585x126
13 4
5
6
3.0
3.0
3.0
405x174
450x174
405x210
450x90
495x90
450x126
450x210
495x210
540x210
540x126
585x126
630x126
14 4
5
6
3.5
3.5
3.5
450x174
405x210
450x210
495x90
450x126
495x126
495x210
540x210
585x210
585x126
630x126
675x126
15 4
5
6
3.5
3.5
3.5
405x210
450x210
495x210
450x126
495x126
540x126
540x210
585x210
630x210
630x126
675x126
720x126
16 4
5
6
4.0
4.0
4.0
450x210
495x210
540x210
495x126
540x126
585x126
585x210
630x210
675x210
675x126
720x126
765x126
17 4
5
6
4.0
4.0
4.0
495x210
540x210
585x210
540x126
585x126
630x126
630x210
675x210
720x210
720x126
765x126
810x126
18 4
5
6
4.5
4.5
4.5
540x210
585x210
630x210
585x126
630x126
675x126
675x210
720x210
765x210
765x126
810x126
855x126
19 4
5
6
4.5
4.5
4.5
585x210
630x210
675x210
630x126
675x126
720x126
720x210
765x210
810x210
810x126
855x126
900x126
20 4
5
6
5.0
5.0
5.0
630x210
675x210
720x210
675x126
720x126
765x126
765x210
810x210
855x210
855x126
900x126
945x126

Nothing contained in this material shall be construed as  a warranty or otherwise as to the accuracy or safety of the information provided. Specific design work should be carried out by qualified engineers.

Benefits

Economy – This type of portal has a proven cost saving record. Surprisingly, industrial projects already designed in steel, have been changed to TimberLab Angle Knee Portals to take advantage of cheaper costs.

Shape – Because of the clean lines of the TimberLab Angle Knee Portal, maximum height is obtained at the knee. This is especially significant for sporting facilities.

Simplicity – The pre-finished and stained members need a minimum of site handling. Shoes are factory fitted and once secured to anchor bolts on site, a few bolts at the apex complete the erection.

Purlin Fixing – Unique to this portal are the built-in purlin cleats. These are factory glued between the rafter panels and extend up to provide simple and direct fixing for purlins. This means that pre-cut purlins can be used to tie the portals together at pre-determined spaces. Girt block can also be built into the columns.

Note: Corbels to support floor beams can be incorporated into the column section of these portals for two storey construction.

Applications

Gymnasiums, churches, school halls, sporting facilities, factories, storage buildings, swimming pools.

Two storey buildings and gantry supporting corbels are also able to be incorporated in the versatile portal design. This portal form may also be adapted to provide clerestory profiles.

Specifications

See Specification Data Sheet
Note: Resorcinol glue should always be used for cross lap joints at the knees.

Quality Control

TimberLab Solutions Ltd is a licensed manufacturer, independently audited under AS/NZS 1328 for Glulam manufacture and AS5068 for finger jointing; license No. 2915/6. Regular in-factory quality control is carried out in conformance with these and internationally equivalent standards.

Services Available

  • Free cost estimates
  • Experienced advice on suitability of Glulam design options
  • Full engineering design and drawing facilities
  • Complete building packages including design, manufacture, supply of all connections and components, and installation supervision
  • Close liaison and client satisfaction are high priorities in TimberLab’s personal care.