Floor Cassettes: A Framer's Guide to Prefabricated Floor Panels
Module Building Systems
Floor cassettes are prefabricated floor panels: joists, rim and blocking built in a factory as large sections, with decking where specified, then lowered onto bearings your crew has already prepared. At Module Building Systems (MBS), we build floor cassettes to your drawings on our St. Louis line, so your framers set a planned floor instead of rolling out loose joists one at a time.
Crews are short right now. In the September 2026 NAHB/Wells Fargo Housing Market Index survey, 57% of builders reported a shortage of framing crews, up 9 percentage points from April 2025 (NAHB Eye on Housing, Oct. 14, 2026). Framing is also a big line in the budget. NAHB's latest cost survey puts it at 16.6% of construction cost for the average new home, behind only interior finishes and major system rough-ins (NAHB Eye on Housing, Jan. 23, 2025).
A floor deck is repeat work. Same joist spacing, same blocking line, same rim, sheet after sheet of decking. Repeat work belongs in a plant, and your crew's time belongs on the set.
What is a floor cassette?
A floor cassette is a load-bearing section of floor framing, built off site and set on the job as one piece. Cassette is the common word in the UK and Australia. Here you will also hear prefabricated floor panels or a panelized floor system. Same idea.
We supply floor framing in coordinated sections: the designed joist system, rim and edge support, and decking where specified. An I-joist floor is one example. Your engineer picks the system, and joist size, spacing and fastening follow the project drawings.
That is the difference from a loose floor truss or I-joist package. Those arrive as single members, and your crew spaces, blocks and decks each one on the plates. A cassette arrives with the layout already built in. Floor cassettes sit in our framing lineup next to prefab wall panels, roof panels and subcomponents.
Decked or open
Order cassettes with decking where specified, or open if your crew prefers to deck in the field. Either way, we agree the deck joints and the field work with you before we build. A deck joint that lands where your crew expects it is one less surprise on set day.
How does our line build floor cassettes?
We build floor cassettes from the same drawing set your crew works from. The project model becomes assembly drawings, then CNC shop drawings, then cut lists for the line. Our CNC crosscut saw cuts within 1/16 inch. That figure describes where the saw's length-stop positions each board, not a tolerance for a finished floor.
Then we assemble each cassette: joists to the layout, rim and edge support, blocking where the drawings call for it, and decking if the order includes it.
Every cassette leaves with the identification marks we agreed with you, and the delivery list ties those marks to your set plan. Your foreman knows which piece comes off the truck first and where it lands.
How do you install floor cassettes?
You install floor cassettes by lowering each section onto bearings your crew has already prepared, then connecting it to the walls, beams and the next cassette. The project lift plan sets the crane setup, rigging, pick points and temporary bracing. The project installation plan covers handling, connections and the work between sections.
We plan each delivery around the next stage of your framing job. On a two-story house, the second-floor cassettes arrive once the first-floor walls are standing and checked. No cassette sits in the mud waiting for its walls.
Settle four things before the load leaves our plant:
- Bearing dimensions on site, checked against the drawings
- Truck access, staging space and the unload
- The crew and lifting equipment for set day
- Which cassettes set first, and where the field joints fall
A planned load beats a pile. Our flat-pack delivery guide covers trucks, racks and staging in more detail.
Where do stairs, plumbing and ductwork go?
Stairs, plumbing drops and duct runs go where the drawings put them, and we plan the cassette divisions around them before we cut a board. Stair openings, penetrations, bearing interfaces and any required site closures stay coordinated between our shop drawings and your field work.
Bring your plumber and HVAC sub into the drawing review early. Holes in engineered joists follow the joist maker's rules and the engineer's details. A big duct run is far easier to solve on paper than on the deck.
How do floor cassettes compare on cost with stick framing?
Compare floor cassettes with a stick-framed floor on the same completed scope, not on the lumber line alone. Run both options through your own crew numbers:
- Supplied assemblies, plus the materials you still buy
- Field labor for layout, blocking, decking and connections
- Freight, unloading and lifting
- Field completion: joints, closures and anything else your crew finishes
Our quote covers only the framing, sheathing, decking and factory work expressly listed, with freight and installation responsibilities spelled out. Price walls and floors together, too. A wall panel package and floor cassettes on one order let us plan both around the same bearings.
Your crew still lays out, sets, connects and braces. We take the repeat cutting and assembly. If you want a smaller first step, start with prebuilt headers and door legs on one job. Our page for builders, GCs and framers shows every assembly you can order.
About Module Building Systems
Module Building Systems (MBS) is a panelized offsite construction company founded in 2023 and based at 921 N 20th Street in St. Louis, Missouri. We build wall, floor and roof panel packages in a 40,000 sq ft CNC manufacturing facility and ship them flat-packed within 1,000 miles. Projects run up to 30% lower in cost and up to 50% faster, with up to 90% less waste. Actual schedules depend on project scope, approvals, site readiness, materials and logistics. Learn more about MBS.
Frequently asked questions
Are floor cassettes the same as floor trusses?
No. A floor truss is a single member your crew sets, spaces and blocks one at a time. A floor cassette is a whole section of floor framing, with the joists, rim, edge support and decking where specified already assembled. A cassette can use the joist system your engineer specifies, such as I-joists, and it sets as one piece.
Do floor cassettes need a crane?
The project lift plan answers that. It sets the crane setup, rigging, pick points and temporary bracing for the job, based on section size, site access and the set sequence. Agree the crew and lifting equipment with us before the truck leaves our plant, so the right machine is on site when the first cassette comes off.
Who sets MBS floor cassettes?
Your crew does. We build and ship the cassettes, and your framers set, connect and brace them, then finish the field work in your scope. Every section carries the identification marks we agreed on, and the delivery list matches those marks to your set plan, so your foreman runs the set without hunting for pieces.
Can floor cassettes come with the decking on?
Yes. We supply decking where specified, or we ship the cassettes open so your crew decks on site. Agree the deck joints and the field work before manufacture, so the sheets break where your crew expects and the joints between cassettes match the plan. Your quote lists exactly what we deck.
What do you need to quote floor cassettes?
Send the current plans with framing and structural details, openings and the drawing revision. Tell us which products you want, the site address and target date, and your field approach: crew, equipment and the work you keep. We price from those drawings and list every factory inclusion, plus freight and installation responsibilities.
Send us your next floor
Send the drawings for one real job and we will price the floor cassettes your crew needs. Get an estimate, book a factory tour to see the line, or email info@modulebs.com.
Floor cassettes are prefabricated floor panels: joists, rim and blocking built in a factory as large sections, with decking where specified, then lowered onto bearings your crew has already prepared. At Module Building Systems (MBS), we build floor cassettes to your drawings on our St. Louis line, so your framers set a planned floor instead of rolling out loose joists one at a time.
Crews are short right now. In the September 2026 NAHB/Wells Fargo Housing Market Index survey, 57% of builders reported a shortage of framing crews, up 9 percentage points from April 2025 (NAHB Eye on Housing, Oct. 14, 2026). Framing is also a big line in the budget. NAHB's latest cost survey puts it at 16.6% of construction cost for the average new home, behind only interior finishes and major system rough-ins (NAHB Eye on Housing, Jan. 23, 2025).
A floor deck is repeat work. Same joist spacing, same blocking line, same rim, sheet after sheet of decking. Repeat work belongs in a plant, and your crew's time belongs on the set.
What is a floor cassette?
A floor cassette is a load-bearing section of floor framing, built off site and set on the job as one piece. Cassette is the common word in the UK and Australia. Here you will also hear prefabricated floor panels or a panelized floor system. Same idea.
We supply floor framing in coordinated sections: the designed joist system, rim and edge support, and decking where specified. An I-joist floor is one example. Your engineer picks the system, and joist size, spacing and fastening follow the project drawings.
That is the difference from a loose floor truss or I-joist package. Those arrive as single members, and your crew spaces, blocks and decks each one on the plates. A cassette arrives with the layout already built in. Floor cassettes sit in our framing lineup next to prefab wall panels, roof panels and subcomponents.
Decked or open
Order cassettes with decking where specified, or open if your crew prefers to deck in the field. Either way, we agree the deck joints and the field work with you before we build. A deck joint that lands where your crew expects it is one less surprise on set day.
How does our line build floor cassettes?
We build floor cassettes from the same drawing set your crew works from. The project model becomes assembly drawings, then CNC shop drawings, then cut lists for the line. Our CNC crosscut saw cuts within 1/16 inch. That figure describes where the saw's length-stop positions each board, not a tolerance for a finished floor.
Then we assemble each cassette: joists to the layout, rim and edge support, blocking where the drawings call for it, and decking if the order includes it.
Every cassette leaves with the identification marks we agreed with you, and the delivery list ties those marks to your set plan. Your foreman knows which piece comes off the truck first and where it lands.
How do you install floor cassettes?
You install floor cassettes by lowering each section onto bearings your crew has already prepared, then connecting it to the walls, beams and the next cassette. The project lift plan sets the crane setup, rigging, pick points and temporary bracing. The project installation plan covers handling, connections and the work between sections.
We plan each delivery around the next stage of your framing job. On a two-story house, the second-floor cassettes arrive once the first-floor walls are standing and checked. No cassette sits in the mud waiting for its walls.
Settle four things before the load leaves our plant:
- Bearing dimensions on site, checked against the drawings
- Truck access, staging space and the unload
- The crew and lifting equipment for set day
- Which cassettes set first, and where the field joints fall
A planned load beats a pile. Our flat-pack delivery guide covers trucks, racks and staging in more detail.
Where do stairs, plumbing and ductwork go?
Stairs, plumbing drops and duct runs go where the drawings put them, and we plan the cassette divisions around them before we cut a board. Stair openings, penetrations, bearing interfaces and any required site closures stay coordinated between our shop drawings and your field work.
Bring your plumber and HVAC sub into the drawing review early. Holes in engineered joists follow the joist maker's rules and the engineer's details. A big duct run is far easier to solve on paper than on the deck.
How do floor cassettes compare on cost with stick framing?
Compare floor cassettes with a stick-framed floor on the same completed scope, not on the lumber line alone. Run both options through your own crew numbers:
- Supplied assemblies, plus the materials you still buy
- Field labor for layout, blocking, decking and connections
- Freight, unloading and lifting
- Field completion: joints, closures and anything else your crew finishes
Our quote covers only the framing, sheathing, decking and factory work expressly listed, with freight and installation responsibilities spelled out. Price walls and floors together, too. A wall panel package and floor cassettes on one order let us plan both around the same bearings.
Your crew still lays out, sets, connects and braces. We take the repeat cutting and assembly. If you want a smaller first step, start with prebuilt headers and door legs on one job. Our page for builders, GCs and framers shows every assembly you can order.
About Module Building Systems
Module Building Systems (MBS) is a panelized offsite construction company founded in 2023 and based at 921 N 20th Street in St. Louis, Missouri. We build wall, floor and roof panel packages in a 40,000 sq ft CNC manufacturing facility and ship them flat-packed within 1,000 miles. Projects run up to 30% lower in cost and up to 50% faster, with up to 90% less waste. Actual schedules depend on project scope, approvals, site readiness, materials and logistics. Learn more about MBS.
Frequently asked questions
Are floor cassettes the same as floor trusses?
No. A floor truss is a single member your crew sets, spaces and blocks one at a time. A floor cassette is a whole section of floor framing, with the joists, rim, edge support and decking where specified already assembled. A cassette can use the joist system your engineer specifies, such as I-joists, and it sets as one piece.
Do floor cassettes need a crane?
The project lift plan answers that. It sets the crane setup, rigging, pick points and temporary bracing for the job, based on section size, site access and the set sequence. Agree the crew and lifting equipment with us before the truck leaves our plant, so the right machine is on site when the first cassette comes off.
Who sets MBS floor cassettes?
Your crew does. We build and ship the cassettes, and your framers set, connect and brace them, then finish the field work in your scope. Every section carries the identification marks we agreed on, and the delivery list matches those marks to your set plan, so your foreman runs the set without hunting for pieces.
Can floor cassettes come with the decking on?
Yes. We supply decking where specified, or we ship the cassettes open so your crew decks on site. Agree the deck joints and the field work before manufacture, so the sheets break where your crew expects and the joints between cassettes match the plan. Your quote lists exactly what we deck.
What do you need to quote floor cassettes?
Send the current plans with framing and structural details, openings and the drawing revision. Tell us which products you want, the site address and target date, and your field approach: crew, equipment and the work you keep. We price from those drawings and list every factory inclusion, plus freight and installation responsibilities.
Send us your next floor
Send the drawings for one real job and we will price the floor cassettes your crew needs. Get an estimate, book a factory tour to see the line, or email info@modulebs.com.