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Wanting to combine glulam portal frame with plywood box walls and roof.
Not sure where to start

Woodsolutions Answer +

Your portal frame will need engineering design. Some suppliers provide a basic design and take-off service, however it might not extend to more complicated portal frame designs. If you have difficulty finding a consulting engineer with experience in this area Timberbuilt could help, website here: Regarding plywood box beams, our Technical Design Guide #7 titled Plywood Box Beam Construction for Detached Housing gives span tables for commonly used members. The Guide can be downloaded here:

Box beams

Do you have tables showing the shear capacity of timber using batten screws - for bearers for example ?

Woodsolutions Answer +

The shear capacity of a screw that you will find on manufacturers' websites may be the capacity of the screw itself, not necessarily the capacity of a connection made with that screw. The capacity of a screwed connection will depend on the type of timber and its Joint Group, as well as the properties of the screw (gauge, type of metal, etc.) Details of screw capacities can be found in Australian Standard 1720, Timber Structures, Part 1: Design Methods. 

Batten screws

I'm looking at a jetty structure with the support posts submerged partially in an artificial pond. It is not in a marine environment ie not in seawater.
I'm just wondering which timber types (softwood or hardwood) would be more appropriate in this application for the post, bearers and joists?

Woodsolutions Answer +

If the jetty is a permanent structure, intended to have a long service life, the supporting timber could be preservative treated pine or a durable hardwood. In fresh water, H5 level treatment is required for pine, in accordance with Australian Standard 1604 Part 1. Suitable hardwoods would be those with a Durability Class 1 rating, eg. any of the ironbarks, grey box, tallowwood etc. If the bearers and joists are well above the waterline, H4 preservative treatment would suffice for pine. If the jetty is not intended to have a long service life, timbers of lesser durability or lower preservative treatment could be considered.

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