- Terms covered
- Six
- A ModBox home is
- Modular
- Built to
- Ontario Building Code
- Ends up on
- A permanent foundation
- Not sold by ModBox
- RTM, kits, home packages
What is the difference between prefab, modular, and RTM homes?
Prefab is the umbrella term for any factory-made home. Modular means whole sections built to the Ontario Building Code and set permanently on a foundation. RTM means the house is built complete and moved in one piece. A manufactured or mobile home is different again: built to CSA Z240 and kept on a steel chassis.
Builders use these words loosely, which is why one company can turn up in a search for prefab, modular, and ready-to-move homes. The label is the least reliable part of the listing. Ask instead the two questions that change your mortgage, your insurance, and your resale value: which building code was it built to, and does it end up on a permanent foundation.
Every term, side by side
| Term | What it is | Built to | On site |
|---|---|---|---|
| Modular home | Whole 3D sections built indoors, delivered nearly finished | Ontario Building Code, same as a site-built house | Set permanently on a foundation; services connected after set |
| Prefab home | Umbrella term for anything factory-made: modular, panelized, and kits all count | Depends entirely on which kind it is | Depends on which kind it is |
| RTM (ready-to-move) | Built complete, then moved in one piece rather than in sections | Built to the applicable building code | Set on a foundation; route width limits the size of the house |
| Panelized / kit / home package | Factory supplies panels, trusses, and materials; a local crew assembles | Built to code on site, inspected on site | You carry the site labour and the schedule |
| Manufactured / mobile home | Built on a permanent steel chassis at the factory | CSA Z240, a separate standard from the building code | Stays on its chassis; often on leased land |
| Tiny home | A size rather than a construction method, usually under 500 sq ft | Either the building code or an RV standard. Ask which. | Foundation or trailer, depending on the standard it was built to |
Which one is a ModBox home?
Modular. ModBox builds whole sections indoors at its Thunder Bay plant, engineered to meet or exceed the Ontario Building Code, then delivers them and sets them permanently on your foundation. Wood modular, light steel frame, and custom or commercial buildings all follow that same method.
That means a finished ModBox home is a house in every sense that matters to a lender or an insurer. It is not a mobile home, a trailer, or a kit you assemble yourself. Browse the wood line, light steel frame line, or custom and commercial work, and the build process guide walks the whole sequence from drawings to set day.
Does buying a home package save money?
Sometimes on paper, rarely once the site work is counted. A package moves the labour, the schedule, and the weather risk back onto you, and in Northern Ontario those are the costs that overrun. A modular home arrives nearly finished, which is where the schedule protection comes from.
The comparison worth making is total delivered cost rather than sticker price. Our cost guide breaks down which lines exist and who carries each one.
What about tiny homes, garden suites, and ADUs?
Those are uses and sizes, not construction methods. A small modular unit can serve as a garden suite or additional residential unit, but your municipality sets the rules for setbacks, height, servicing, and parking, and those vary across Ontario. Confirm what your lot allows before you choose a model.
If a compact footprint is what you are after, the smaller wood layouts and the steel frame studio are the natural starting points. The standard it is built to is the part not to compromise on: a unit built to a recreational-vehicle standard is not the same asset as one built to the building code, however similar the two look in photographs. The modular basics guide covers that distinction in more detail.
Is a prefab home the same as a modular home?
Not quite. Prefab is the umbrella term for any home whose parts are made in a factory. Modular is one kind of prefab: whole three-dimensional sections built to the Ontario Building Code, then set permanently on a foundation.
What is an RTM home?
Ready-to-move. The house is built complete in a yard or factory and then moved to the site in one piece rather than in sections. It is a transport method more than a separate product, and width limits on the route cap how large an RTM house can be.
What is a home package?
A kit: the factory supplies the materials and often pre-built wall panels or trusses, and a local crew assembles the house on your lot. You are buying components plus drawings, not a finished building, so the labour and schedule stay your responsibility.
Is a modular home the same as a manufactured or mobile home?
No. A manufactured or mobile home is built to CSA Z240 and stays on a steel chassis. A modular home is built to the Ontario Building Code, the same code as any site-built house, and is set permanently on a foundation. That difference drives financing, insurance, and resale.
Can a modular home be a tiny home?
Yes, if it is built to the building code rather than to a recreational-vehicle standard. Small footprint and building standard are separate questions, and the standard is the one that decides whether you can finance it, insure it, and live in it year-round.
Can a modular unit be used as a garden suite or ADU?
Often, but your municipality decides. Additional residential unit rules for setbacks, height, servicing, and parking vary across Ontario, so confirm what your lot allows before choosing a model.
Which term should you search for when shopping?
Search all of them. Builders use these words inconsistently, so the same company can appear under prefab, modular, and RTM. The label matters less than two questions: which building code is it built to, and does it end up on a permanent foundation?