30 Mar The prefab solution to building challenges
New-home construction is a cutting-edge industry.
There’s been a range of advancements creating better outcomes for clients and contractors, but few have been as effective in the past half-decade than prefabrication.
There’s a raft of reasons why it makes sense to create a home’s components in an offsite facility and then have them delivered to the project for assembly and fitting. The end result is improvement in time/cost/quality outcomes.
While a range of building components can be prefabricated – from tilt-slab concrete walls to bespoke joinery – I believe the most exciting outcomes are around structural and architectural features.
A great example is Cross Laminate Timber (CLT). A few years ago, we adopted CLT as a primary building material in our projects.
CLT sees layers of parallel timber beams laid atop one another in a perpendicular fashion. They’re then glued together, resulting in a framing material that’s inherently stronger and more workable than most alternatives.
Best of all, it’s offsite prefabrication for structural components demonstrates exactly why it pays to ‘go remote’ with build items.
Here’s why I’m a fan of prefab, and CLT in particular.
Protected from the elements
Weather events are of major concern when it comes to cost and time blowouts.
A huge fall of rain, high winds or even excessive heat can create not only long delays for your build – it can result in damage to in situ materials and already completed work.
By prefabricating offsite in an enclosed building, items are protected from the outside during manufacture. This means they can be worked on without regard to lousy climate and kept away from excessive moisture in a controlled environment.
They can then simply be delivered to the site when the weather clears for assembly and installation.
Architects and designers love to push the envelope on how finished sections of the build will look. Prefab allows you to lay out what you want and, with the help of heavy-duty, immobile machinery, make it a reality.
In fact, tricky curves or unusual angles are often best designed, measured and machined away from the site because the components will be best completed with pinpoint accuracy in a controlled environment by a computer-driven process.
Modern technology has reached the point where millimetre-perfect design and rendering is entirely possible with the right hardware and software. In many respects, prefab means you don’t need to ‘measure twice, cut once’ because once entered into the program, the results will be more precise than can be achieved by hand.
It all allows for a perfect fit on site, reducing time and costs. The jigsaw of pieces that arrive can be slotted together much faster and with full expectation that the end result will be seamless.
Variations can be the source of frustration and headaches, particularly is they could have been avoided by better upfront communication and/or investigations.
Other changes that can occur include increases in the scope of work or changesin selected products. These are normally alterations made during construction in response to the practicalities of the build. It might be that a client wishes to shift a window frame slightly to catch a particular view, or additional light fittings and power points might be needed in certain rooms.
Having a communication plan allows the client to reach out to the builder and discussthe changes and their implications in astructured manner, so there are no misunderstandings come handover and final payment.
Another advantage CLT prefab provides is it can be more easily reworked onsite than other materials if needed.
Say an element arrives at the project but it requires a slight alteration due to an unforeseeable issue – for example, perhaps a little extra clearance will be available once part of an architectural beam has been safely shaved back a few millimetres.
Prefab CLT can be altered onsite if needed. A far better outcome than with steel or concrete. In fact, modification can be made with a hand or circular saw.
Insulation and Safety
Apart from machining, prefab materials can have additional work carried before delivery.
For instance, say you have problem with erecting scaffold due to neighbouring access. CLT can be pre-lined offsite. This means it’s simply lifted into place ready to go with just a coat of paint and touch up needed.
CLT is also fire retardant – it’s a mass timber and, as such, will char and burn at a set rate per hour in compliance with codes. This is especially handy on tight allotments with limited access as you don’t need to add additional layers of fire rated materials on site.
In short, prefab makes good sense. It’s been proven project after project as the best way to reduce cost for owners, and speed up the process for contractors resulting in better quality builds in less time – and that’s prefab fabulous for everyone.