Replant
Every door has a tree behind it
We mill our own joinery, which means we know exactly how much timber goes into a house. So we count it, work out how many trees that was, and put three seedlings back into the ground for every one. Then we publish where they are, and go back and check they are still alive.
This counter adds up the planting ledger below and nothing else, so it can never drift away from what actually went into the ground. It says about because some of these went in before we started keeping this record, and the count comes from the team rather than from a planting sheet. Everything from here on is written down on the day it happens.
How it works
We measure the timber, because we cut it
Every door, frame, ceiling, floor, wardrobe and roof truss on your job passes through our own workshop. We already know the volume, because we bought the timber and machined it. Nothing here is estimated from a national average.
We convert it to standing trees
Sawn timber is converted back to roundwood using a 45 percent sawmill recovery, which is at the low end of what Kenyan mills achieve. That is deliberate: assuming poor recovery means assuming more roundwood, which means planting more trees. Roundwood is then divided by the volume of a mature tree of that species, and the answer is always rounded up.
You get the number in writing
On handover you get a page that says, in plain terms, what your house took out of the ground. Five internal doors in cypress, for instance, works out at 2 mature trees.
We plant three back for every one
One for one is not restitution. Roughly two in five seedlings die in their first three years, and a seedling is not a tree for twenty. Three covers the losses and leaves a real surplus.
You choose where they go
On your own land, on the project site as part of the landscaping, into a Kenya Forest Service adopt-a-forest block, or with a school or community group. If you have nowhere to put them, we place them and you still get the coordinates.
We come back and check
Survival is checked at 6, 12, 24 and 36 months. Anything that has died inside 3 years is replaced at our cost. The results go into the public ledger whether they are good or not.
What this does not claim
Planting a tree does not undo felling one. A seedling is not a substitute for a twenty year old cypress, and it will not be for two decades. This programme is restitution over time, not a carbon offset and not a licence to use timber carelessly. The bigger thing we do for the forest is buy from licensed plantations rather than from whoever is cheapest, and dry the timber properly so a door lasts fifty years instead of being replaced twice.
Work it out
What would your joinery take out of the ground?
Set the quantities for the house you are planning. It opens on a fairly typical four bedroom house, so change whatever does not match. The roof structure usually surprises people, because nobody thinks of a roof as joinery.
Doors, windows and fitted joinery
per each · 0.960 m³ sawn
A 900 by 2100 leaf with its frame and architraves, plus machining waste.
per each · 0.280 m³ sawn
Heavier sections and usually a hardwood, so it carries several times the timber of an internal door.
per each · 0.350 m³ sawn
per m² · 1.320 m³ sawn
per m²
per linear metre · 1.320 m³ sawn
per linear metre · 0.540 m³ sawn
per linear metre
per each
Structure and roof
per m² of roof · 6.750 m³ sawn
Usually the single largest timber item in a house, and the one nobody thinks of as joinery.
per linear metre
Furniture and loose pieces
per each
per each
per linear metre
Formwork and temporary works
per m² of slab
What this took out of the ground
32
mature trees, from 11.52 m³ of sawn timber
What goes back
96
seedlings, 3 for every tree, kept alive for 3 years or replaced
Where the timber goes
- Roof structure, trusses and purlins · Cypress6.75 m³
- Fitted wardrobe · Cypress1.32 m³
- Timber ceiling, boards and battens · Cypress1.32 m³
- Solid timber door and frame · Cypress0.96 m³
- Kitchen units · Cypress0.54 m³
- Timber window frame · Cypress0.35 m³
- Double main entrance door and frame · Mahogany0.28 m³
9.5 tonnes of CO₂ held in the timber
Wood is about half carbon by dry weight, and it stays locked up for as long as the timber lasts. A door that survives fifty years is a better outcome than one replaced twice.
Working figures reviewed August 2026, using 45 percent sawmill conversion. Deliberately conservative, so the tree count errs high rather than low. Nothing you type here leaves your device.
What a tree is worth, in timber
The figures behind the arithmetic. A mature tree yields a surprisingly small amount of usable timber once it has been through a mill, which is the whole reason this programme is affordable and the whole reason it matters.
| Species | Roundwood per tree | Time to maturity | What we use it for |
|---|---|---|---|
| CypressCupressus lusitanicaThe workhorse of Kenyan joinery. Grows well at this altitude and takes a finish nicely once it is properly dried. | 0.8 m³ | 20 to 25 years | Doors, frames, roof timber, ceilings, general joinery |
| PinePinus patulaFast and straight. Needs treating for anything in ground contact or exposed. | 0.9 m³ | 18 to 25 years | Roof structure, formwork, props, second fix |
| GrevilleaGrevillea robustaGrown on farm boundaries all over this region, so it is usually the most local timber available. | 0.45 m³ | 12 to 18 years | Framing, shelving, furniture carcasses |
| EucalyptusEucalyptus grandis and salignaVery fast growing and heavily planted. It is also thirsty, which is why we do not recommend planting it near a house or a spring. | 0.55 m³ | 8 to 15 years | Props, scaffolding, poles, formwork bearers |
| MahoganyIndigenousKhaya anthothecaSlow and valuable. A mahogany door is a forty year tree, which is worth knowing before you specify six of them. | 1.3 m³ | 40 years and up | Main entrance doors, feature joinery, furniture |
| Meru oakIndigenousVitex keniensisA Kenyan indigenous hardwood under real pressure. We use it sparingly and only from documented plantation sources. | 1.1 m³ | 40 years and up | Flooring, feature joinery, furniture |
| CamphorIndigenousOcotea usambarensisBeautiful and extremely slow to replace. Worth thinking hard about before specifying. | 1.4 m³ | 50 years and up | High end joinery and furniture |
Working averages reviewed August 2026. A tree on good ground with room around it beats them, a crowded one does not.
The ledger
Every planting, in public
Date, count, species, place, coordinates and survival. Published so that anyone, including you, can go and stand in front of the trees. The record lives in the website version history, so an entry cannot be quietly edited after the fact.
Site to be confirmedApproximate
Before the ledger started- Trees
- about 320
- Trees replaced
- Not recorded
- Still alive
- Not yet counted
- Species
- Not recorded
Planted before this ledger existed, so the count is from the team rather than from a planting record. Everything from here on is recorded on the day it goes in.
Not building with us? You can still use this
The calculator above works for any joinery, not only ours. If you have had doors or a roof made somewhere else and you want to know what it cost the forest, use it. If you would like us to plant the trees for a job we did not build, we will do that too, at cost.
Questions
- Does this cost me anything?
- No. It is included in the joinery, not added to it. The trees themselves are a very small cost against a joinery order, and we would rather absorb it than turn it into a line item you could decline.
- How do you know how many trees my joinery used?
- Because we mill it ourselves and bought the timber. We take the sawn volume in your order, convert it back to roundwood at 45 percent sawmill recovery, and divide by the volume of a mature tree of that species. The recovery figure is deliberately at the low end of what Kenyan mills achieve, so the tree count comes out high rather than low, and the answer is always rounded up.
- Why three seedlings and not one?
- One for one is not restitution. Roughly two in five seedlings die in the first three years, so one for one would leave you short before anything had grown. Three covers the mortality and leaves a genuine surplus. It also acknowledges that a seedling is not a mature tree for twenty years.
- What if I have nowhere to plant them?
- Most people do not, and it changes nothing. We place them into a Kenya Forest Service adopt-a-forest block, a school, or a community conservation project, and you still get the location and the coordinates. You can visit them whenever you like.
- How do I know they were actually planted?
- Every planting is recorded in the public ledger on this page with a date, a count, a place, coordinates and photographs. The record is kept in the website's version history, so entries cannot be quietly changed afterwards. Survival is checked at 6, 12, 24 and 36 months and the results are published whether they are good or not.
- Is this a carbon offset?
- No, and we will not describe it as one. A carbon credit is a regulated instrument with rules on additionality, permanence, measurement and verification, and under Kenya's Climate Change (Carbon Markets) Regulations 2024 it needs NEMA approval, registration and a community benefit sharing agreement. This programme meets none of that and does not try to. It is restitution for timber we used, recorded honestly.
- Would planting indigenous trees be better?
- Usually yes for the ecosystem, and usually slower for timber. We plant a mix, and where the site suits it we prefer indigenous species even though they take forty years rather than twenty. What we avoid is planting eucalyptus near water or near houses, because it is very thirsty.
- Should I just avoid timber altogether?
- Probably not. Timber grown in a plantation and harvested is a renewable material that stores carbon for as long as it lasts, which compares well with steel, aluminium and concrete. The problems are illegal logging and short lived products. Buying from licensed sources and drying properly so the thing lasts fifty years addresses both, and it matters more than replanting does.
Building with timber? Let us count it properly.
Tell us what joinery your house needs. You will get a price, and you will get a number of trees, and both of them in writing.