JengaCost explained: from a plot and a budget to a priced bill of quantities
If you have asked a fundi, a friend or a quantity surveyor what a house will cost to build in Kenya, you have probably heard "it depends", followed by a figure per square metre that nobody could explain. JengaCost was built to give you a real answer in minutes, and to show you where every shilling goes.
What JengaCost is
JengaCost is a construction cost estimator for Kenya. You pick a house, either one of the 37 ready designs or one you describe, along with the county you are building in. You get:
- a floor plan, a section and a 3D model of the house;
- a bill of quantities: every item of work measured and priced, from the foundation trenches to the last coat of paint;
- the plot works, such as the boundary wall, gate, driveway and septic tank, priced separately;
- prices adjusted to your county, one of 47;
- a steel schedule and a materials list for ordering.
It is free to start, with no account needed to explore. It's built for how Kenya builds: machine-cut stone, mabati or flat concrete roofs, county rates and M-Pesa.
How it works out the cost
Most quick estimates multiply the floor area by a rate per square metre. That number hides everything that makes one house dearer than another, such as a bigger roof, a second storey, more bathrooms or a long boundary wall.
JengaCost prepares a bill the way a quantity surveyor does:
- It measures the building. Every quantity comes from the drawn model: cubic metres of excavation and concrete in the foundations, square metres of walling with the door and window openings taken out, ring beams and slabs, the roof by its true sloped area, each door and window, plaster, floors, ceilings, paint, wet rooms and electrical points.
- It prices each quantity from a Kenyan rate library in which every rate is dated and has a low, typical and high figure. The whole library is public on the price index.
- It adjusts to your county, because cement and steel cost more the further they travel, and labour rates differ.
- It adds what self-builders forget: an allowance for county approval fees, the NCA levy, transport of materials to site, and temporary water and power.
Anything the library cannot price yet is listed by name, never guessed. You can open every line, change any rate, and save the bill as a project.
| Approvals, permits and setting up | KES 248,705 |
| Foundations to floor slab | KES 648,887 |
| Walling, frame and upper floors | KES 562,023 |
| Roof | KES 678,262 |
| Doors, windows and services | KES 666,864 |
| Finishes and fittings | KES 762,236 |
| External works | KES 1,026,185 |
| Total, house and plot works | KES 4,593,163 |
The bill, in the format you need
The same measured building can be issued three ways: as a cost plan by element, for budgeting and comparing; as an SMM7 measured bill; or, on Pro, as the detailed elemental bill a Kenyan QS issues, numbered element by element and floor by floor. For ordering there is a steel take-off by bar diameter in 12 m lengths, and a materials schedule in bags, tonnes, pieces and feet.
Choosing between houses
Few people know at the start which house they want. Most have a budget, a plot and a number of bedrooms. On the compare page, enter those and JengaCost finds the catalogue houses nearest your brief. You can then add up to four houses yourself, or the same house at a different finish or with a different roof. They are priced side by side at your county's rates, with:
- the cost of the house, the plot works and your contingency;
- space, cost per square metre and how much of your plot each house covers;
- how long each takes to build, and what isn't priced yet;
- where the money differs between the top two, stage by stage.
Tell it what matters to you most, such as cost, space, value, speed or fewest unknowns, and the houses are ranked on those priorities, with the reasons in plain words. A house over your budget never ranks above one that fits.
Building in stages
Most Kenyan houses are built as the money comes. Enter the cash you have now and what you can put aside each month, and JengaCost shows which stages your cash pays for today, when each later stage can start, and when the house is finished. There is more on this in our guide to building in stages.
From estimate to real quotes
Once you have a bill, send it for quotes. Suppliers on JengaCost list what they sell, so each is sent only the lines they supply, with the quantities already measured. A paint company prices the paint and a pipe merchant prices the pipes. Architects, structural engineers and quantity surveyors can quote their fees from your brief. Imported materials are shown with their cost on site, not just their price at a port abroad; the landed cost calculator works out duty, levies, VAT and clearing.
What it is not
A JengaCost estimate is a budget, not a contractor's quotation. Prices move, and a site can hold surprises. Its drawings are concepts for deciding and budgeting. County approval needs drawings from a registered architect and structural engineer. The estimate doesn't include professional fees, the land, utility connection fees or furniture. See what is not included.
What it costs to use
Exploring, comparing and planning are free, and so are 2 saved projects with full bills. Pro is KES 1,500 a month, paid by M-Pesa. It adds unlimited projects, the detailed QS-format bill, the AI designer and AI take-off from your own plans. A single extra project with its bill is KES 400.