With the increase in warehouse and distribution center projects going up to feed the demand of an ever-increasing population, coupled with rising steel costs, now may be the right time to consider total precast as an alternative to traditional tilt-up with steel joist structure. Here are a few thoughts to help you make the right choice.
Structure – Steel roof construction can be used in conjunction with both precast concrete and tilt-up walls. However, with precast, another option is to build a total precast structure with precast columns, beams, and double tee roof members. As steel prices skyrocket, a total precast option presents real cost saving opportunities.
Schedule – The majority of precast lead time is in the design phase, which can be minimized by overlapping precast design with the development of construction documents. Precast shop drawings and production drawings are often developed concurrently with contract documents and precast production usually occurs simultaneously with earthwork and foundations. With steel joist lead times already extending into next year, a total precast structure can help mitigate schedule delays and even accelerate the schedule.
Trade Sequencing – Tilt-up panels require the slab or casting bed to be in place prior to commencing, whereas precast walls are erected before to the building slab. Precast does not use the slab, so steel framing install can begin shortly after and follow the precast. Steel lintels or angles for joist bearing can be installed ahead of time in the precast manufacturing facility, further minimizing labor on-site.
Precast walls are available with integral, continuous insulation, which delivers schedule savings and further reduces the number of trades required on-site. Unlike post-applied insulation types, the interior wythe of concrete is exposed to the building interior in the final condition. This provides a durable surface ideal for manufacturing, industrial, and high-use spaces.
Less impact on site offers more room for other trades to move forward with the rest of the project.
Site Location – The site’s geographical location must also be taken in consideration. Tilt-up is dependent on season and weather whereas precast is produced indoors, eliminating dependence on season, cold temperatures, and extreme weather conditions. Precast can be manufactured unrestricted year-round.
To produce tilt walls on site, adequate space and ideal conditions for casting and curing must be present. Tilt-up panels’ consistency depends upon a flawless casting surface. However, due to sequence, the casting surface is poured in an unprotected environment, increasing the probability of imperfections and joints in the slab can translate to the face of the panel. Precast has few site limitations as it is cast and cured in a manufacturing facility. A total precast structure has the added benefit of protecting the building slab while it is being poured and curing. Not only does the precast offer a higher quality finish than tilt-up, it furnishes an environment to pour a higher quality floor.
