John Teunon – Owner Operator


MacJac Sheds is owned and operated by John Teunon. John has been building sheds for over 20 years and added MacJac Sheds to his J&A Constructions (Aus) Pty Ltd  group in 2016. We specialise in “kit only” supplies together with building the complete project shed, commercial constructions and commercial concreting!

We offer our own professional steel erection and concreting crews to compliment the MacJac Shed sales which ensure a quality steel build! Our team has a great deal of experience in designing and building sheds to suit all types of purposes – residential, farm and commercial clients.

We use all Australian products with galvanised steel frames which ensure our sheds are built tough to last. We use quality materials that ensure a durable result with nice aesthetic quality finish. If you need a high quality shed designed and built to meet your individual specifications then call on our shed design and build experts!

We can design supply and build your quality steel project:

  • Garden sheds
  • Carports & Garages
  • Residential sheds
  • Farm sheds
  • Hay sheds
  • Commercial Buildings

Macjac’s prefabricated kits are manufactured by A-Line Building Systems, making for easy erection.  All columns and rafters are manufactured from world leading Structural premium galvanised RHS (Rectangular Hollow Steel) which has undergone chemical and mechanical treatment for corrosion control.  The product also has an in-line galvanised rust inhibiting zinc finish and a clean bright visual appearance providing a fully welded and bolted frame with heavy fascia for fixing gutters and wall sheets.


Fully engineered footing plans are supplied using Bolt cages.  The cages are supplied with the Bolts already connected to the Reinforcing Cage, eliminating the need for steel fixing, welding, and a template. This ensures accurate alignment of poles to bolts when the pole is erected. 

MacJac Sheds is one of the few manufacturers in New South Wales who can not only offer RHS but also C-Section (cold rolled purlins) frame types which are made of lightweight materials and are generally a cheaper option.  Please advise if you would like us to pursue a price on this alternate option.

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