Almost every client starts with the same question: “How much will my duplex cost?” The honest answer is that it depends, but it depends on factors you can control. Once you understand them, you can plan with confidence instead of guessing.
What decides the cost of a duplex
1. Floor area. A bigger building needs more blocks, cement, roofing and labour. A 235 square metre four-bedroom duplex will cost noticeably less to build than a 270 square metre five-bedroom plan. Browse our duplex plans to compare floor areas before you decide.
2. Finishing level. Tiles, ceilings, doors, sanitary ware, lighting and kitchen fittings can swing a budget more than the structure itself. Decide your finishing level early and write it down.
3. Site conditions. Sloping land, poor soil, flood-prone areas and bad access roads all add cost. A proper site survey and consultancy review before you commit prevents expensive surprises.
4. Number of ensuite rooms. Every ensuite adds plumbing, tiling and fittings. A plan with many ensuite bedrooms is more comfortable, but it costs more per room.
5. Material prices and timing. Cement, iron rods and roofing sheets change in price. Buying in stages without a procurement plan can leave you paying more for the same materials.
How to budget by stage
Most residential projects move through these stages, and your budget should follow them:
- Design and approvals
- Foundation and substructure
- Blockwork and structural frame
- Roofing
- Electrical and plumbing first fix
- Plastering, screeding and tiling
- Finishing, painting and external works
Set aside a contingency of roughly 10 to 15 percent for price changes and unforeseen site issues. This is a common rule of thumb, not a quote.
Four ways to avoid overruns
- Start with a complete, construction-ready design. Changing the design mid-build is the most common cause of overspending. See our architectural design service.
- Get a detailed bill of quantities so every material is priced before work begins.
- Use professional supervision. Poor site control wastes materials and time. Our project management service covers procurement, site coordination and quality control.
- Build with a registered, accountable company that gives you a clear schedule and transparent pricing.
Get a realistic number for your project
Every site and design is different, so the most accurate figure comes from a consultation. Contact us or chat with us on WhatsApp with your plot size and preferred plan. You can also request our free cost estimate guide, which covers duplex and bungalow requirements in Nigeria.
See our completed projects and read the answers to common questions in our FAQ.