Wednesday, July 11, 2018

“D1D”, the Day One Difference

A couple of weeks ago as I was looking through LinkedIn I noticed Ken Semler, the owner of Express Modular, used the term “D1D” when talking about the big advantage modular home construction has over other offsite construction methods.

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

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.

An Entekra Home being set

Day One: Panelized

Years ago I was a GC that built panelized homes, mostly custom two story center hall colonials, so I am speaking from first hand experience.

On my typical Monday, 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.

Today a few of the more innovative panelized manufacturers like Entekra and Katerra ship the flooring in prefab sections making for a more efficient process but not nearly as fun to watch.

Watching videos of an Entreka panelized home being set I noticed that they are in most cases able to set both the 1st and 2nd floor systems and the interior and exterior wall panels. Very impressive but to be perfectly honest my 5 man crew would hand build both floors and set the same number of panels in one day.

In both cases the trusses were and probably still are set and sheathed on the second day.

That brings us to what Ken calls ‘D1D’.

A modular home being set by The Home Store

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 most areas, walls have been painted with a primer paint, interior and exterior doors have been installed along with most of the trim throughout the house.

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

Thanks Ken for giving an easy to use term to describe the modular housing industry’s unique benefits for homeowners.


Anonymous said...


I am a modular builder and enjoy your blog. Having said that, I think the Day One Difference is a disingenuous concept for us to promote.

Once buyer commits to purchase:

Panelization - pour foundation and then set walls. If timing is good, can probably completed in 3-4 weeks.

Modular - pour foundation set home. If timing is good, 8-10 weeks.

Spec home building is somewhat different. Time is money and builder is working off their own money. Timing and carry costs are different. Modular actually has a slight advantage. But, most modular is custom built for a specific customer.

Coach said...


I don't know of any site builder that can pour a foundation, set panels and completely finish a house in 3-4 weeks. If this were the case every builder in the US would be doing it and there would be no housing shortage. And also no need for modular or manufactured housing.

The point of the article was what happens on the first day AFTER the foundation is poured and the sill plate attached. Hence the Day One Difference.

I don't care when the buyer 'commits' to purchase because planning and code enforcement plus change orders levels the playing field.

I stand by the article.

VM said...

Right on Coach!
D1D on using Modular makes better performance time. Hands down , panelized will be slower.
There is not a panelized Builder anywhere that would be telling the truth if they stated other wise.
All we need the industry to do now is accommodate the gold rush of business that Modular Construction is bringing to the USA.