The Five Types at a Glance
Here’s a quick guide to materials, fire ratings, and typical use cases.
- Type I — Fire-Resistive: Reinforced concrete/Protected steel; highest fire ratings. Common for high-rises, hospitals, large public buildings.
- Type II — Non-Combustible: Unprotected or lightly protected steel/concrete; moderate ratings. Warehouses, big box retail, newer schools.
- Type III — Ordinary: Non-combustible exterior walls (masonry/CMU) with combustible interior framing (wood/steel mix). Main-street mixed use.
- Type IV — Heavy Timber/Mass Timber: Large wood members or CLT/GLT with inherent fire performance. Modern mid-rise, civic buildings.
- Type V — Wood Frame: Combustible exterior and interior framing (stick-built). Single-family, townhomes, small commercial.
Fire Resistance & Code Implications
Fire-rating requirements drive assemblies, cost, and inspections.
- Rated assemblies: walls, floors, columns may need 1–3 hr ratings
- Protection: spray fireproofing, gypsum layers, intumescent coatings
- Penetrations: firestopping around MEP is a common inspection fail—plan it early
- Height/area limits: differ by type and occupancy; additions may trigger upgrades
Typical Materials & Detailing Considerations
Choose assemblies that meet rating and budget without complicating install.
- Type I/II: steel/concrete; watch for fireproofing takeoffs and curing time
- Type III: masonry exterior + wood/steel interior; manage parapet ratings and ledger connections
- Type IV: mass timber/HT; coordinate char-rate details, connectors, and moisture control
- Type V: wood studs; staggered studs, fire-rated gypsum, draftstopping in attics/floors
Estimating & Scheduling Impacts
Construction type changes your labor, long-lead items, and inspections.
- Assemblies: include exact UL designs in your estimate and alternates for VE
- Long leads: mass timber packages, steel, fire doors, rated glass—lock early
- Inspections: pre-cover for firestopping, shaft walls, spray fireproofing adhesion
- Allowances: include contingencies for patch/repair after MEP rough-ins
Common Risks (and How to Avoid Them)
A few misses cause most delays and change orders.
- Mismatched ratings: submittals don’t match plans → reference UL numbers on POs and RFIs
- Penetration chaos: no sleeves or wrong firestop → coordinate MEP layouts before framing
- Moisture in wood/mass timber: protect deliveries; track MC before cover
- Detail drift: field substitutions without engineer/architect approval → use EWAs/COs
How Construction Type Affects Billing & Documentation
Rated work and specialty trades benefit from granular tracking.
- Break out rated assemblies and firestopping in your Schedule of Values
- For T&M changes, attach photos of penetrations, patch, and firestop to invoices
- Collect vendor COIs and keep inspection sign-offs with pay apps
Where Werx Helps
Werx keeps takeoffs, changes, and billing aligned to the building type and code requirements.
- Create optioned estimates with alternates for assemblies
- Track rated work in Contract Projects with SOV lines
- Capture EWAs and convert to COs; bill via AIA/progress or T&M
- Log time/photos in the Werx Field App; collect online payments
FAQs About Building Construction Types
Who determines the construction type?
The design team sets it on the code sheet and AHJ confirms during plan review. Field changes that affect ratings require approval.
Can a building mix types?
Yes—additions, podiums, and separations can create mixed types. Fire walls and horizontal assemblies may allow different types in one project.
How does type affect insurance and cost?
Higher fire resistance often lowers risk but increases material/labor cost. Coordinate with the owner and insurer early when selecting assemblies.
TL;DR Recap
- Types I–V define fire resistance and materials—driving code and cost
- Include rated assemblies and firestopping in your estimate/SOV
- Coordinate penetrations and inspections early to avoid rework
- Werx links estimates, EWAs/COs, and billing for cleaner approvals
