Advice
Cost premiums with mass timber are offset by the more rapid construction process with pre-fabricated construction.
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Advice
Fire departments are an overlooked stakeholder.
Advice
Not all contractors are equally familiar with mass timber requirements but many are eager to gain experience. Pre-qualification for mass timber experience should be undertaken as a selection criteria.
Advice
CLT requires significant pre-construction coordination, for example with modelling. Either hire a specialty firm or specify that the General Contractor (or sub contractors) model and coordinate CLT and MEP.
Advice
Specs should outline General Contractor responsibility for 1) coordinating CLT delivery and storage; and 2) providing 3rd party moisture testing.
Advice
Specs should request written description of moisture protection protocol (submitted prior to CLT delivery), describing protection implementation plan for each stage: — delivery — storage — installation (roof & floor panels) — after installation (walls) — ongoing moisture protection measures until exterior envelope is watertight — remedial measures for panels damaged and/or stained during installation
Advice
Reasons to engage the services of a CLT installer during design: — gives rigour to cost and scope — gets structural modelling info and connection details — provides site sequencing and mobilization info — provides contractor costs for installation
Advice
Costs can easily inflate for MEP (mechanical, electrical, plumbing). Contractors go to suppliers for pricing, suppliers add contingency costs, contractors add their own contingency, and the cost can inflate enough to kill the project.
Advice
Spec a target tolerance. Contractually this is difficult to hold to, but provides a method to explain the importance of the allowable tolerance.
Advice
More advanced technologies can be used for water and fire management to reduce and speed up on-site work.
Advice
Mass panel installation advice: — Full scale mockup is a benefit, allows best practices to be developed and solutions identified prior to construction. — “Install prefab guardrail systems between columns on the perimeter and pre-determine tie-off points for worker safety” — Manufacturers need to clearly identify and locate balanced panel lifting points. — Pre plan and optimize truck load stacks, delivery schedules and erection sequencing
Advice
Peel and stick membranes on CLT panels is inadequate for inclement weather. The best solution is to erect rapidly and install building envelope ASAP.
Advice
Virtual design and construction modelling (VDC) is very important, as it identifies constructibility issues and associated costs, helping reduce the number of changes and speeds up the schedule. It is also a form of quality control on timing, scheduling, coordination, fine details, and safety.
Advice
Prefabrication advantages: — Higher quality components that are more precisely manufactured are produced, which reduces installation time, schedule length, and site deliveries. — Waste on site is reduced, saving disposal costs — Concurrent off site work can take place in controlled conditions. — Change orders are reduced in number — Mass panel penetrations are well lighted up, making MEP runs easier — Negligible shimming and furring and adjustments — Reduced number of fastening steps on site results in the structure being enclosed more quickly