Sunday, May 16, 2021

"Day 1 Difference" is the Key to Modular Construction's Success

Years back when I was a general contractor in Pennsylvania, I built exclusively with wall panels and trusses. Completing the shell of a typical 2 story home took two days because my panel factory couldn't provide floor trusses and my framing crew had to build the floors on site.


On the first day, the lumber yard delivered the floor joists, floor sheathing, joist hangers and rim joists. The truck would drop the entire load on the ground. The lumber yard I used packed the truck with the sheathing on the bottom and the joists on top making it look like an upside-down pyramid all banded together.

When the truck driver raised the bed the load slid off with the bands breaking and all the joists followed the OSB sheathing on what looked like a toboggan ride across the lot. Looking back on it today, watching that happen at job after job was funny.

By the third day, we were shingling the roof and beginning the 90-120 day process of completing the home. At that point, I had not been introduced to modular construction.

Ken Semler, the owner of Impresa Modular, and I were talking recently about the speed to completion of a modular home compared to what I used to build and he used the term "Day 1 Difference" when talking about the big advantage of modular home construction has over other offsite construction methods.

He was using the term to describe an imaginary stopwatch on a new home job site comparing panelized construction with modular construction. Now he had my interest.

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For simplicity let’s assume two-story, 3 bedroom, 2 bath homes are being built side by side in a development. Both have their foundations and sill plates done and are waiting for the house to begin being built.
Day One: Panelized

Today, panelized manufacturers like Entekra ship the flooring in prefab sections making for a more efficient process.

Watching videos of an Entreka panelized home being set I noticed that in most cases able to set both the 1st and 2nd floor systems and the interior and exterior wall panels in just one day. Very impressive.


The typical panelized home still needs another 60-90 days to complete which can be even longer today with the shortage of both LBM and skilled labor.

"Day 1 Difference"


Day One: Modular

6:00 AM-7:30 AM crane arrives and sets up.
7:30 AM-4:00 PM the four modules are set and the roof is raised.
4:00 PM-6:00 PM +/- the roof is completely shingled

That timetable is fairly typical. What is amazing about this process is the amount of finish work both on the interior and exterior of the home that has been done in the factory.


Electrical is run throughout the house with switches, receptacles, lights and smoke alarms complete. In some states, the fire sprinkler system has been installed. Interior house plumbing pipes, water lines and fixtures have been installed as well as the kitchen cabinets, countertops and even some appliances.

Carpeting and vinyl flooring is installed in most areas, walls have been painted with primer paint, interior and exterior doors have been installed along with most of the trim throughout the house.

The typical time to completion for a modular home is 30-45 days.

Ken Semler has begun using the term “Day One Difference” to help his buyers better understand the advantage of modular construction but I don’t think he would mind in the least if you start using it too.


Gary Fleisher
is the Managing Director and contributor to the Modcoach Network and its affiliated blogs. Email at modcoach@gmail.com.

1 comment:

Empire Window Company said...

The videos are amazing! I like that show "zero waste" on the construction site. Even the windows are a perfect fit!
Empire Window Company