Effective planning of sites is critical for delivery of mass-timber building projects, a leader in multi-storey timber construction says.
Speaking during a webinar featured on Australian wood products information site Wood Solutions, Karla Fraser, Director of Construction at Hive Projects Inc. and Cape Group in Vancouver, Canada, shared her experience in leading multiple tall-timber developments.
These include the eighteen-storey UBC Brock Commons Tallwood House in Vancouver (pictured above), which at its completion in 2016 was the world’s tallest mass timber building.
According to Fraser, successful delivery of mass timber projects requires strategies across several areas.
The first – and the focus of this article – involves planning your site.
When doing this for mass timber projects, Fraser says several things are needed.
First, it is important to receive input from tradespeople and to understand delivery requirements throughout the project.
When performing construction sequencing, input from trades such as mechanical and electrical can help to determine matters such as the size and weight of HVAC units which need to be installed and the curbs which will be required.
Trade input also helps to determine the size of the crane which is needed. On one project, Frasers’s team found that the required crane size was determined not by the core boxes but rather a small but heavy piece of mechanical equipment.
Further, where equipment is to be split into multiple parts rather than delivered as a whole, it may be possible to downsize the crane.
Fraser says the importance of trade input should not be underestimated. Should issues with insufficient access points for product or equipment installation be uncovered during later project stages, consequences can be serious.
Depending on the project, it can be important to engage with other stakeholders. In Vancouver, Fraser says many of her firm’s developments are located on busy roads and there are multiple infrastructure projects underway throughout the city. This means it is critical to liaise with the city about when deliveries will occur, where they will come from and which roads may be blocked or affected. In doing this, input from trades about delivery requirements will be necessary.
Fraser says the importance of trade input should not be underestimated.
“It is fantastic if we are servicing an excavating contractor, but if we forget that at the end of the day we are still going to be putting final products into the building and access points don’t make sense, this can be difficult for the project overall,” Fraser said.
“Here in Vancouver, we have to do strategic planning for the city of Vancouver in order to identify how trucking routes are going to come into the city because they have lots of infrastructure projects going on. We now are constrained in at least six different communities (where they are delivering projects) where we have to communicate what the project is going to look like throughout the entire time that we are building and where our trucking is going to be coming from.
“So we sit down with our superintendents and our trade superintendents and we go through everybody’s input from the formworker to the mechanical trades and electrical trades and we identify how we are going to service the site.”
Next, it is important to ensure that there is enough room for the water management system as well as staging areas.
In the case of the Brooke Commons project, Fraser says the dewatering system was initially set to be placed in the front. By moving this to the back and instead running water alongside the back the building and out, the team was able to free up space at the front of the building to have a full trucking thoroughfare.
Another important decision is where laydown and delivery areas will need to be situated. On large projects, Fraser says determining where laydown areas will be needed and for how long at various project stages can be tricky and can require multiple planning sessions.
Finally, when working with mass timber, it is important to think about the largest panes and whether these can be delivered without impacting neighbouring properties. Speaking particularly of Vancouver, Fraser says there is much sensitivity about activities which impact neighbouring properties. Given this, along with the fact that renting space on neighbouring properties is generally not possible, planning is critical.
Next, it is important to think about the size of the crane which will be needed.
When doing this, it is important to review the sizes and weights of equipment which is needed and to seek trade input when doing this.
It is also important to think about how the building will be loaded and whether a hoist or crane will be more suitable. On the Brooke Commons project, use of a hoist was not possible because the required construction timeframes meant that the bottom floors needed to be loaded in by the time the top floor was to be reached. Should you wish to use a hoist, Fraser says it is important to ensure that you have the required space and access.
Next, it is important to plan your utilities and water management.
Speaking particularly of Vancouver, Fraser says it is necessary to determine the timing of the hydro connection and to ensure that payment is made by the due date. Where payment is late, connections can be delayed by either twelve or 24 weeks from the date of payment.
Apart from hydro, it is important to ensure that remaining connections have been confirmed by the city. In the case of Vancouver, the project team typically performs the surveying and this is later approved by council. Whereas in previous times, survey information was simply obtained from the city, this is no longer efficient and is now prone to error as the city has had multiple contractors perform its surveying over the years.
It is also important to determine the size and location of tanks which will be needed for environmental water management and to ensure that there is room on site to accommodate these. Whilst larger tanks will be needed toward the beginning of projects, smaller ones may suffice as the development progresses.
Last, there must be a convenient location for the temp hydro throughout construction. This should be out of the way of any panels which need to be installed.
Finally, the site plan needs to include all safety and emergency information. This is critical as this is the plan that will be sent out to trades, included in contracts and will form part of ongoing communication onsite.
Whilst this information will also be shown on safety boards, it should also be included as part of the live site plan as safety boards are not always read by everybody.