Modular home being installed at site.

Compelling Pros and Cons of Prefab or Modular Home Construction

Modular home units being assembled on the site at the New Jersey shore.
Modular home units being assembled at the Jersey Shore!

Prefab is an umbrella term that covers any home partly built in a factory. It includes everything from modular homes that arrive in just a few sections — complete with attached walls, flooring and even finishes — to what are called panelized homes, which are delivered in smaller pieces. The following case study investigates how homeowners came to the decision to utilize this method for their home construction.

Deciding to go Prefab

The homeowners, my close friends and an active family of 5, were interested in purchasing a fun home along the New Jersey Shore. After an extended search, they found a home on an ideal plot of land in Manasquan. Unfortunately, the home had endured damage from Hurricane Sandy in 2012 and was infested with mold. After an additional search, they returned to this location with the intent to raze the existing home and rebuild.

The Process of Modular Home Construction

The NJ contractor Coastal Modular Group, who has worked extensively with modular homes, was chosen and the process began. Familiar with the requirements of this construction, the contractor was able to facilitate the design of the home with the homeowners. One of the parameters included size limitations due to transportation on the US roads. It was decided that this home would consist of (2) 15 foot wide units to maximize the plot coverage allowances. The units would butt together with a laminated beam supporting the opening between them. A locally licensed architect collaborated with them, providing plans for the connection specifications, site work and building department applications.

Once the design is complete and permits attained, the site can be prepared simultaneously while house construction proceeds in the factory.

Demolition and Removal of Existing Home

It is surprising how quickly a building can be brought down. Demolition included removal of the home and its foundation along with the cleaning of the property. Total time for this home on the existing property was completed within 2 days!

Foundation and Site Preparation to Receive the Modular Home Units

Pat Valentine Ziv of PVZ Design, LLC visits the Modular Home construction site.
Interior designer Pat Valentine Ziv visits the construction site while modular home units are installed upon the pilings.

In this case and in accordance with new construction codes in this shore area, pilings are installed into the ground to receive the weight of the building. There are no basements and the first floor is simply a garage with stair access to the home above along with shaft space for an elevator. The lots are small and the homes are usually 3 floors high – an elevator would be a welcome amenity for people of all abilities. The ground floor limitation is a preventive measure to minimize property damage in the event of future storm flooding.

Electrical and plumbing hook-ups need to be brought to the site in preparation of the home’s connections. Grading of the site is necessary to accommodate any landscaping such as driveways, gravel, plantings, etc.

Why choose a MODULAR HOME or WHY NOT?

Assembly begins with floor at the modular home assembly line.
The beginning of the modular home assembly line at the Durabuilt Custom Homes LLC factory.

The decision to choose a modular home over the conventional stick-built home was a conscious one after much research. Here are some of the advantages of the factory built home.

THE PROS

Overall Speed of construction

Modular construction allows for the building and the site work to be completed simultaneously greatly reducing overall construction time. The exact amount of time will depend on the degree to which the home module has been ordered and the amount of finish work still needed on site. In some cases, the home is brought with roofing, siding and interiors requiring only finish paint to complete the project. In our case, Coastal Modular Group prefers to do the siding, interior flooring and fixtures on site. Nevertheless, the home will arrive with electrical and lighting, plumbing and most cabinetry already installed. In all cases, connections to the site are needed as well as correcting any other issues such as cracks in the sheetrock.

Indoor construction

Work is more consistent, efficient and safe. The home is built without weather delays. All building components are stored, dry, clean, and protected inside the manufacturing facility.

There are no extreme weather conditions to contend with in a factory. Skilled workers can concentrate on the task at hand without dealing with the numbing cold or stifling heat. Safety in a factory is far superior to working in the elements. Access to a roof is significantly sturdier than a ladder pitched on soil.

Low Waste and Sustainability

While waste from a site-built project may typically fill several large dumpsters, construction of a modular home generates much less waste. The manufacturer calculates the exact quantity of materials needed for a given modular home. Manufacturing several units in one location provides efficiency in procuring large amounts of building materials to fulfill the needs of the various projects.

Quality and Consistency

Measurements and accuracy are consistently checked. Quality control is essential to the process of Modular Home construction making the overall product more airtight, plumb and consistent.

The modular home units are being transported to their NJ site.
Modular units on their way to the their new location in Manasquan, NJ from the Durabuilt Custom Homes LLC factory.

THE CONS

Here are some disadvantages to Modular construction:

Size Limitation of the Project

Size limitations, as mentioned before, are an important factor. The units need to be transported on the roads restricting their width and height. They can, however, be combined with elaborate engineering.

Sheetrock Stress Cracks

Cracks in the sheetrock are a reoccurring problem that has not been economically solved despite many attempts. These issues are corrected at the site.

Difficult to Make Changes Once Fabrication has Begun

Due to the efficiencies in purchasing and construction mentioned above, changes will disrupt the flow and timing of the project. It is therefore critical to allow for much time and thought to the design of your new home.

Your architect, interior designer and the contractor’s input is invaluable as their experience and pre-emptive design solutions will allow for a beautiful result for your exterior elevations and interior design.

Requires a Contractor Specifically Knowledgable about Modular Homes

Contractors who work with modular home construction need to be educated in the idiosyncrasies of the connections, the structure and its weight bearing loads in order to properly integrate the product with its new site.

Your Research is Critical

It is important to research your factory and contractor to ensure that they are well suited to collaborate together. This is a team effort and all parties must understand their roles. In some cases, the homes are supplied to the site complete with siding and flooring and in others, the local contractor prefers to install certain products at the site. This is something that you, as the homeowner along with the contractor and factory need to agree upon. As your interior designer, I am happy to assist you with these and the many decisions required during the design phase of the project and beyond. As mentioned before, it is better not to change anything after a design has been approved making this design process a very crucial step in the process.

It is important to confirm that your Building Department understand that there will be an inspection of your unit with a third party certified inspector addressing the needs of your state and local codes. They will visit the factory periodically to assure that your unit is prepared in accordance with all codes required in your jurisdiction. This is extremely important, as your unit will arrive with walls hiding electrical, plumbing and structure. It will not be possible for your local inspectors to examine these. There will be additional inspections for the pilings and connections at the site and prior to the Certificate of Occupancy.

My Conclusions

I had the pleasure of a guided tour at Durabuilt Custom Homes LLC, the modular home factory located in central Pennsylvania who was building the home shown in the accompanying photos. A long time proponent of modular home construction, I was excited to visit this factory and better understand this manufacturing and construction process.

In my opinion and after visiting the factory and being present on site during the installation with the contractor, Coastal Modular Group, I am confident that modular homes are a great alternative to conventional stick built homes on site provided you have researched your factory and contractor as well as considered the pros and cons. Modern factory construction techniques assure outstanding quality and have very high standard specifications.

Durabuilt Custom Homes LLC factory assembly line.
A modular home unit on the assembly line of the Durabuilt Custom Homes LLC factory.

As an interior designer, I especially appreciated the added blocking where the window treatments will need to be secured. From a construction point of view, here are some items I was pleased to find:

  • Impact resistant windows that are air tight and weather resistant for our future hurricanes.
  • Additional bracing with constant attention to square corners to assure the safe and secure travel that these units need to endure.
  • Pre-drilled studs to accommodate wiring.
  • Blocking and foam insulation at all electrical outlets.
  • Laminated beams to extend large distances at the interior connection for open room layouts.
  • Tankless high efficiency water heater as an energy efficient choice that heats water as needed rather than keeping a tank of water heated for when you may use it.

On the other hand, I see a serious need to correct the sheetrock issue. Maybe the installation of sheetrock at the site will not only solve the cracks issue but may allow for minor revisions to be made more easily.

Many of these benefits contribute to an environmentally friendly and sustainable home. Your selection of energy efficient products will add to your green design if that is your direction.

There is a place for the modular home in our region and it would be wise to consider this alternative. I would be thrilled to assist you in the process of designing and building your new modular home. Call me at 201 233-4636 or e-mail me at pat@pvzdesign.com.

Pat Valentine Ziv, ASID, CID, is a NJ Certified Interior Designer and a professional member of the American Society of Interior Designers. She holds an Architectural Design degree and possesses in-depth knowledge of buildings and their systems.


Leave a Reply