Floor Extension with LGSF — Turnkey
Floor extension means increasing the area of an existing building by constructing an additional floor on top, without demolition or new foundation. Using an LGSF frame (25–40 kg/m²), this is possible without foundation reinforcement in 4 out of 5 cases. Cost — from $430 /m², timeline — from 2 months.
Key Facts About LGSF Floor Extension
What is a floor extension and who needs it?
A floor extension is building reconstruction by adding one or more additional floors on the existing roof. Instead of buying a new land plot and building from scratch, the owner gets additional 200–2,000 m² of space in 3–5 months. LGSF technology allows doing this without stopping business operations.
Expanding office space without relocation — the most common order type
Additional retail space, food courts, entertainment zones
Utility and administrative premises above the workshop without stopping production
Offices, dispatch rooms and break rooms on the second level
Additional departments and wards without new construction
New classrooms, laboratories, libraries without changing the plot
Increasing room capacity with minimal impact on operations
How much does a floor extension cost in Ukraine in 2026?
The cost of a turnkey LGSF floor extension is from $430 to $650 /m² depending on area, purpose and finishing level. For a typical 500 m² project, that's $215,000–$325,000. The exact price is determined after a free building inspection.
| Premises type | Area | Price $/m² | Total |
|---|---|---|---|
| Office (standard) | 500 м² | 480–550 | 240–275 K $ |
| Production | 500 м² | 430–500 | 215–250 K $ |
| Shopping center | 500 м² | 520–650 | 260–325 K $ |
| Mansard | 500 м² | 380–480 | 190–240 K $ |
Compare with rent and new construction → | Calculate the cost →
Why is LGSF the only technology for extensions without foundation reinforcement?
An LGSF frame weighs 25–40 kg/m² — 3–5 times lighter than concrete (150–250 kg/m²) and 2–3 times lighter than wood (40–60 kg/m²). It is the only technology that in most cases allows adding a floor without foundation reinforcement costs — saving $15–40 K.
| Parameter | LGSF | Wood | Concrete |
|---|---|---|---|
| Frame weight, kg/m² | 25–40 | 40–60 | 150–250 |
| Foundation reinforcement | Rarely (20%) | Sometimes (40%) | Almost always (90%+) |
| Frame installation time | 15–30 days | 20–40 days | 60–120 days |
| Business interruption | No | Partially | Yes |
| Winter installation | Yes | Limited | No |
| Fire resistance | REI 45–90 | REI 15–30 | REI 120+ |
| Service life | 50+ years | 30–50 years | 50+ years |
Will the foundation withstand a floor extension?
In most cases — yes. According to DBN V.2.1-10:2018, foundations are designed with a safety factor of 1.2–1.5, meaning a 20–50% reserve. An LGSF extension adds only 60–80 kg/m² (accounting for old roof demolition), which usually fits within the reserve.
Allowable additional load = Foundation bearing capacity − Current building load
If extension weight ≤ allowable additional load → reinforcement is not needed.
Calculation example
Typical office building from 1985, 2 floors, footprint 500 m²:
| Parameter | Value |
|---|---|
| Foundation bearing capacity (by design) | 1 000 т |
| Current building load (2 floors + roof) | 750 т |
| Bearing capacity reserve | 250 т (25%) |
| LGSF extension weight 500 m² × 120 kg/m² | 60 т |
| Demolished roof weight 500 m² × 50 kg/m² | −25 т |
| Actual additional load | 35 т (60 − 25) |
| Conclusion | 35 т < 250 т → reinforcement NOT needed |
How does a floor extension work: 6 steps from request to handover?
The full cycle of a floor extension from first call to turnkey handover is 60 to 150 days. ReadyCon performs all 6 stages as a single contractor: survey → design → factory manufacturing → installation → finishing → handover.
Preliminary Assessment
Submit a request. An engineer will visit the site within 1–3 days. Free of charge.
Technical Inspection
5–10 days. Laboratory testing, geodesy, bearing capacity calculation. From $1,000.
Design
2–4 weeks. Structural scheme, connection nodes, load distribution per DBN standards.
Production
3–4 weeks at ReadyCon factory with 1 mm precision. Permits processed in parallel.
Frame Installation
15–30 days. Bolted connections without welding. Business operates as usual.
Finishing & Handover
2–4 weeks. Insulation, facade, roofing, finishing. Handover with full documentation.
What types of extensions can be built with LGSF?
LGSF technology enables four types of extensions: full floor (80–120 kg/m²), mansard (20–30% lighter), technical floor for engineering systems, and annex. Choice depends on foundation reserve, purpose and budget.
Full Floor
Additional 1–2 floors. Weight: 80–120 kg/m². From $430/m².
- Offices & business centers
- Shopping centers
- Administrative buildings
Mansard Floor
Pitched roof with insulation. 20–30% lighter. From $380/m².
- Private houses
- Hotels & hostels
- Educational institutions
Technical Floor
For engineering systems: HVAC, server equipment. From $350/m².
- Business centers & malls
- Medical facilities
- Data centers
Annex
Horizontal area expansion. From $400/m².
- Warehouses & workshops
- Retail pavilions
- Office & utility
Extension vs new construction vs lease — which is more profitable?
A floor extension costs 40–60% less than new construction of equivalent area and pays back in 2–4 years instead of 5–8. Compared to leasing, a 500 m² extension pays back in 3–5 years at a rate of 8–12 $/m²/month.
| Parameter (500 m²) | Extension | New Construction | Lease 5 years |
|---|---|---|---|
| Cost | 240–325 K $ | 400–600 K $ | 240–360 K $ |
| Readiness time | 3–5 months | 12–18 months | Immediately |
| Ownership | Yes | Yes | No |
| Additional land plot | Not needed | Required | — |
| Property capitalization | Increases | Increases | Unchanged |
| Layout flexibility | High | Maximum | Limited |
Completed extension projects by ReadyCon
Extensions and annexes completed by ReadyCon Engineering
What guarantees does ReadyCon provide for extensions?
Fixed Price
Price locked in the contract — no surcharges or hidden costs
Clear Deadlines
Fixed deadlines with contractor financial liability
5-Year Warranty
On structures and installation — legally binding warranty
Staged Payment
Pay after each stage is completed — no large upfront payments
Engineering Supervision
Engineering oversight at every stage — from design to handover
Permits & Documentation
Full documentation package, expertise, commissioning
Free Estimate extension cost
Frequently asked questions about floor extensions
Will the foundation withstand a floor extension?
In most cases — yes. Foundations are designed with a 20–50% safety margin per DBN V.2.1-10:2018. An LGSF frame weighs 25–40 kg/m² — 3–5 times less than concrete. The exact answer comes from a survey, which we conduct free of charge.
How much does a turnkey floor extension cost?
From $430 to $650/m² depending on premises type and finishing level. For 500 m² that's $215,000–$325,000. Price is locked in the contract. Preliminary estimate — free within 48 hours.
How long does a floor extension take?
From 60 to 150 days full turnkey cycle. Design — 2–4 weeks, manufacturing — 3–4 weeks (permits in parallel), frame installation — 15–30 days, finishing — 2–4 weeks. Deadlines are fixed in the contract.
Will business stop during construction?
No. LGSF is a "dry" technology with bolt connections, no welding or concrete work. Your facility continues operating as usual throughout construction.
Is a permit required for a floor extension?
Yes, extensions require design documentation and permits per DBN standards. ReadyCon fully handles design, expertise and permit documentation.
Can you add 2 floors?
Yes, provided sufficient foundation reserve. Two LGSF floors weigh 160–240 kg/m², still 2–3 times lighter than a single concrete floor. Decision is made after inspection.
What is LGSF and why is it suitable for extensions?
LGSF (Light Gauge Steel Framing) is a frame technology using galvanized profiles 0.8–2.0 mm thick. The frame is 3–5 times lighter than concrete, assembled with bolts without welding, withstands REI 45–90 loads, lasts 50+ years.
When is an extension without foundation reinforcement impossible?
Reinforcement is needed for: foundation cracks over 2 mm, weak soils, pre-1960s buildings with less than 15% margin, heavy structure additions. LGSF avoids reinforcement in 4 out of 5 cases.
Can you build an extension in winter?
Yes. LGSF is a "dry" technology with no wet processes. Installation is possible 365 days a year at any temperature. This is one of the key advantages over concrete and brick.
Mansard or full floor — which to choose?
Mansard is 20–30% lighter and cheaper (from $380/m²) but has wall height limitations. Full floor (from $430/m²) — standard 2.7–3.0 m height with no layout restrictions. Choice depends on purpose and budget.
What is the difference between an extension and an annex?
Extension — adding floors upward on an existing building. Annex — expanding area horizontally. Extension doesn't require additional land but is limited by foundation bearing capacity.
Why ReadyCon over other contractors?
ReadyCon is the only full-cycle contractor: survey, design, manufacturing at own factory, installation, handover. 16+ years of experience, 600+ projects, 0 accidents. Fixed price, staged payments, 5-year warranty. No intermediaries.
Sources and Regulatory Framework
- DBN V.2.1-10:2018 — Foundations of structures. Basic design provisions
- DBN V.2.6-198:2014 — Steel structures. Design standards
- DBN V.1.1-7:2016 — Fire safety of construction objects. General requirements
- DSTU B V.2.6-7:2020 — Building structures. LGSF products
Engineering Conclusion
- LGSF frame (25–40 kg/m²) is the only technology that in 4 out of 5 cases allows adding a floor without foundation reinforcement costs
- Savings compared to concrete extension — from 30% of budget and 50% of time, without business interruption
- Full cycle from survey to turnkey handover — from 60 days with a single contractor
Still have questions?
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