Design & planning
Choose a plan, explore changes, understand the property, and define the scope before moving into production.
Meet ModbuildrPersonal attention.
Personal attention.
Practical experience.
A custom home is a big decision. Modbuildr helps you understand the process, weigh your options, and keep your project moving.
Jim SpontarelliFounder & Owner
Your point of contact
Meet Jim.
Jim founded Modbuildr in 2024 to give homeowners a more personal way to navigate custom modular construction.
Before starting the business, he worked in modular manufacturing and custom homebuilding. That experience helps him understand both how a home moves through the factory and what needs to happen on the property.
Today, Jim works directly with clients on land evaluation, design, budgeting, financing coordination, permitting, home installation, and agreed on-site completion. Modbuildr is based in Sunbury, Pennsylvania, and serves projects in Pennsylvania, Maryland, and Virginia.
Start a conversation with JimWhat we help you work throughThe details behind
The details behind
a successful build.
Factory & site coordination
Connect manufacturing, site preparation, foundation work, delivery, crane scheduling, and the home set.
Completion & communication
Coordinate the agreed finish work and inspections while keeping the next steps clear for everyone involved.
Our manufacturing partner
Signature Building Systems.
Modbuildr works with Signature Building Systems in Moosic, Pennsylvania, to bring custom modular designs from plan to production.
Meet Jim at the Signature design center in Moosic by appointment for your final design meeting, a plant tour, and countertop selections. Contact Jim to arrange your visit.
Arrange a visit with JimSupport around your projectThe right people
The right people
for the next step.
Jim can help coordinate design, financing, and real estate support as your project takes shape.
Erica McMillon
Interior design support to help translate your ideas into layouts, finishes, and spaces that feel like home.
Ask Jim about design supportThomas Coronato
Construction lending support through Calcon Mutual Mortgage. Financing availability and terms are determined by the lender.
Visit the lending partner pageBrian Coester
Real estate support through Real Estate Connection for clients exploring property and homebuilding options.
Talk through your property searchYour next step
Let’s talk about the home you have in mind.
Have a plan, a property, or just an idea? Start with a conversation with Jim.