Click on image for full case study on Green Gables Visitors’ Centre.
“The use of mass timber was a natural progression from the traditional
timber framing used within the barn and Phase I addition. Root Architecture
Inc. wanted to continue using exposed wood to fit with
the aesthetic goals of the project, and to provide a more sustainable
approach to the structural frame.
Glue-laminated timber (glulam) makes up 85% of the columns, beams
and trusses, and are left exposed within the facility. All of the glulam
is slotted to receive hidden steel connection plates where possible to
further reinforce the modern look and feel. Connections use a combination
of wood screws, dowels and through bolts. In the other areas,
conventional flat chord and gable trusses are used supported by
wood-frame load-bearing walls built of staggered 2×4 and 2×6 studs
with 2×10 top and bottom plates to reduce thermal bridging.
In Phase II the nail laminated timber (NLT) roof panels were used to
eliminate the traditional use of purlins to create an uncluttered appearance
within the main spaces. NLT is composed of dimensional lumber
set on edge and nailed together to make a single structural element.
With plywood sheathing added to the top faces of the NLT panels, the engineers,
CBCL Limited, designed the panels to provide in-plane shear capacity, allowing for
their use as a structural roof diaphragm. CBCL also designed the NLT panels to support
the gravity loads for spans of 3.8m between supporting elements. The NLT panels are
Apart from their aesthetic qualities, the NLT panels were made within the local community
using local 2×4 materials which offers fast, repetitive fabrication and ease of
erection on site.”