Here is how you build a wood store: set the frame clear of the ground (on slabs or deck supports), keep the sides open to the wind, give the roof a slope of about 8 degrees for drainage and face the whole thing south or south-east, at least 10 cm from the wall.
Stack your wood loosely with air gaps, in logs of 25 to 35 cm, and let it dry until the moisture drops below 20%. Softwood and birch manage that in about a year, hardwood such as oak and beech needs two years.
For an average winter you can count on 4 to 6 cubic metres of dry wood in a well-insulated house. Kiln-dried firewood costs around 250 to 350 euros per m³ when neatly stacked, and quite a bit less loose.
Below you will read exactly how to go about it, from the foundation to the last log on your stack.
Why a good wood store matters so much
Dry wood is half the battle. Wet or damp wood burns badly, gives little heat and produces far more smoke.
The rule of thumb: firewood should contain no more than 20% moisture, and ideally you sit around 12 to 15%. Freshly cut wood often contains 50% moisture or more.
Why does that matter so much?
- More heat. At a moisture content of 15 to 20% the calorific value sits around 4.2 kWh per kilo. Wet wood first spends part of its energy evaporating the water inside the log.
- Less smoke and particulate matter. Dry wood burns hotter and more completely, so fewer unburnt particles go up the chimney.
- Cleaner stove and chimney. Damp wood leaves more creosote build-up, and that increases the risk of a chimney fire.
That particulate point is no detail. Wood burning is responsible for a significant share of fine particulate emissions (PM2.5), and an average evening at the stove releases a notable amount of it.
Burning dry, and not burning in still or foggy weather, limits the nuisance for you and the neighbourhood. A good wood store is the basis: without dry wood, clean burning simply is not possible.
Where do you site your wood store?
The location largely decides how quickly your wood dries.
Facing south or south-east. Sun and wind do the drying work together. You point the open side towards the sun, so the warmth can get well inside.
Not tight against the wall. Keep at least 10 cm of space between the stack and the wall. That lets the wind pass by and keeps your wall dry too. Wood pressed against the wall traps moisture and can damage your brickwork.
Away from the house. A woodpile attracts mice, spiders and sometimes woodworm. So it is better not to put your store right up against the back door or the wooden shed. It keeps pests out of the house and limits fire risk.
In an airy spot that is not too shady. Under a dense tree or in a damp corner wood dries slowly. Wind matters at least as much as sun.
Building your own wood store: the construction
You can make it as simple or as smart as you like. The principles stay the same: clear of the ground, open to the wind, dry from above.
Base: wood must not touch the ground
This is the most important rule. If your wood sits on the ground, it draws up ground moisture and the bottom layer starts to rot.
Options for the base:
- Concrete deck supports or paving slabs under a wooden support frame.
- Pallets as a quick, cheap base (make sure they are sturdy enough).
- Concrete footings with posts for a really solid construction.
Set the supports on a bed of gravel or crushed stone, so rainwater drains away and there is not permanent water sitting under your store.
Frame and dimensions
A handy, stable base size for a self-build wood store is about 1 metre deep and 1.9 metres wide. That is big enough for a decent supply and small enough to stay stable.
Give the roof a slope so water runs off to the front or the back, away from your house. A practical set of dimensions:
| Component | Size (guideline) |
|---|---|
| Frame footprint | approx. 1 m x 1.9 m |
| Height of front uprights | approx. 135 cm |
| Height of rear uprights | approx. 122 cm |
| Roof slope (from height difference) | approx. 8 degrees |
| Gap between side battens | approx. 6 to 7 cm |
Those gaps between the battens of the side walls are deliberate: they let the wind through and keep most of the rain out.
Which wood for the frame?
Your frame stands outside year in, year out, so choose durable wood:
- Pressure-treated softwood is the cheapest, widely available choice.
- Douglas fir or larch is naturally more durable and does not need treating.
Fix everything with stainless or galvanised screws. Anchoring it to the ground or to a wall bracket stops the store blowing over when it is empty.
Roof and back wall
The roof keeps the rain off your stack. Options for the roof covering:
- Corrugated metal sheet (light and cheap).
- Bitumen roof shingles or roofing felt on a wooden base board.
- Clear polycarbonate corrugated sheet if you want to keep some light.
Let the roof overhang slightly at the front, so the rain does not splash onto your wood.
You leave the sides open or half open for air circulation. You can close off a back wall on the side the most rain comes from (often the south-west), but then keep the other sides nice and open.
Stacking firewood: how to do it right
A good stack is stable and airy at the same time. You play those two off against each other a little, and that is what stacking is about.
Split first. Split wood dries far faster than whole round pieces, because the damp core is exposed. Saw and split your logs to 25 to 35 cm, to suit your stove.
Leave air gaps. Do not lay the logs solidly against each other. A little space lets the wind pass through, and that is exactly what the wood needs to dry.
Do not stack too high. Up to about 1.5 to 1.8 metres a loose stack usually stays stable. Higher gets wobbly, especially as the wood shrinks while drying and the stack settles.
Stabilise the ends. The ends of a free-standing stack topple first. Solve that by cross-stacking there (each layer turned 90 degrees, like a little tower) or set uprights or posts alongside.
Bark side up. The bark works like a little roof. Lay logs with the bark on top, then rain runs off better. In the top layer this helps most.
Cover the top only. If you want to use a tarpaulin instead of a roof, lay it over the top only. If you wrap the whole stack, you actually seal in the moisture and your wood sweats instead of drying.
Drying wood: how long and how do you spot dry wood?
Drying is a matter of patience. Exactly how long depends on the species, whether it is split, and on the weather.
Drying time by species
| Species | Type | Drying time (guideline) |
|---|---|---|
| Pine, spruce, softwood | Soft | approx. 1 year |
| Birch | Soft/medium | approx. 1 to 1.5 years |
| Ash | Hard | approx. 1.5 to 2 years |
| Beech | Hard | approx. 2 years |
| Oak | Hard | approx. 2 years or longer |
By way of illustration: split wood in standard size drops to about 28% moisture in a year, and only after roughly two years of good drying do you get below 20%.
Split wood dries faster than round wood, and wood under an airy shelter faster than wood lying flat on a heap.
How do you know it is dry enough?
You do not have to guess. Look out for these signs:
- Cracks in the end grain. Dry wood develops radial cracks at the end.
- Sound. Knock two dry logs together and you hear a clear, hollow clack. Wet wood sounds dull.
- Weight. Dry wood is noticeably lighter than a fresh log of the same size.
- Bark comes loose. In many species the bark comes off easily when the wood is properly dry.
- Moisture meter. The surest way. A wood moisture meter costs little and reads the percentage directly. Measure on a freshly split face in the middle of the log, not on the outside.
An old trick without a meter: smear a little washing-up liquid on the end of the log and blow through the grain from the other side. If bubbles appear on the soap side, the vessels are open and your wood is dry.
How much wood do you need, and what does it cost?
Handy to know before you saw or order: how big does that supply actually need to be?
Use per winter
As a rule of thumb for one winter:
- Well-insulated house, cosy burning a few evenings a week: about 4 to 6 m³ of dry wood.
- Moderately insulated house or burning more often: easily 8 to 12 m³.
- Large house heated mostly by wood: 12 to 15 m³ or more.
If you burn around 4 to 5 evenings a week, you average around 4 to 5 cubic metres per season. Insulation, stove type and species make the difference.
Calorific value by species
Not every cubic metre gives the same heat. Hardwood is denser and lasts longer per log. Handy are the energy values per stacked cubic metre:
| Species | Energy per m³ stacked (kWh, guideline) |
|---|---|
| Beech | approx. 2000 |
| Oak and ash | approx. 1950 |
| Birch | approx. 1770 |
| Pine (softwood) | approx. 1560 |
Softwood actually has a slightly higher calorific value per kilo, but it is much lighter, so you get less heat per cubic metre. It also cracks and spits more because of the resins. For an open fireplace that is a nuisance, but in a closed stove it is fine as kindling.
In short: oak, beech and ash are the top choices for long, warm burning hours. Birch burns nicely and smells good. Softwood is great for getting the fire going.
Cost per m³
The price depends heavily on how dry it is and how it is delivered. Watch the difference between stacked and loose carefully.
| Type | Price (guideline per m³) |
|---|---|
| Kiln-dried, neatly stacked | approx. 250 to 350 euros |
| Kiln-dried/dry, loose | approx. 85 to 150 euros |
| Fresh (still to dry) | clearly cheaper, but adds waiting time |
Why the big difference? A stacked cubic metre contains far more wood than a loose cubic metre, because a loose load has a lot of air between the pieces.
The rule of thumb: 1 m³ stacked is roughly equal to 1.7 m³ loose. So always compare like with like, otherwise loose looks dirt cheap while you get less wood.
Felling fresh logs yourself and letting them dry for two years is the cheapest, provided you have the space and the patience.
What you should not burn
A wood store is for clean, untreated firewood. Stay away from:
- Painted, varnished or treated wood. This gives off toxic fumes.
- Chipboard, MDF, plywood and glued pallet wood. Full of glues and chemicals.
- Wet or mouldy wood. Lots of smoke, little heat.
- Reclaimed wood with nails or leftovers. Bad for your stove and the environment.
Burn only clean, dry and untreated wood. Simple and safe.
Common mistakes
- Stacking wood straight on the ground. The bottom layer rots away from ground moisture.
- Burning too soon. Leaving fresh wood a few months is not enough. Reckon on one to two years.
- Wrapping the stack entirely in plastic. Moisture cannot escape and your wood goes mouldy instead of drying.
- Stacking against the wall. Bad for air circulation and for your wall.
- Mixing up loose and stacked on price. You then pay too much per cubic metre of actual wood.
- Leaving logs too thick. Unsplit round wood dries agonisingly slowly. Splitting speeds everything up.
Maintaining your wood store
It is not much work, but a little attention greatly extends its lifespan.
- Autumn: sweep leaves off the roof, they hold moisture.
- Spring: remove moss and algae, check the base for rot.
- Yearly: check that the frame still stands firm and that the roof covering is still watertight.
- When topping up: burn the oldest supply first. Work with dividers or bays so you know what has been there longest.
Frequently asked questions
How dry does firewood need to be to burn?
No more than 20% moisture, and ideally between 12 and 15%. Above 20% the wood gives less heat, more smoke and more build-up in your chimney. Measure it with a wood moisture meter on a freshly split face.
How long does wood need to dry before you can burn it?
Softwood and birch are usable after about a year of good drying. Hardwood such as oak, beech and ash needs two years or longer. Split wood under an airy shelter dries faster than round wood or wood on a dense heap.
Can I store firewood outside?
Yes, storing outside is fine and even better for drying than in a closed shed, provided the wood stands clear of the ground, stays dry from above and the wind can pass by. An open wood store with a sloping roof is ideal.
Should I cover my woodpile with a tarpaulin?
Only over the top, never wrap it completely. A tarpaulin or roof keeps the rain off, but the sides must stay open so moisture can escape. A stack sealed entirely in plastic will sweat and go mouldy.
How many cubic metres of wood do I need for a winter?
For a well-insulated house where you burn a few evenings a week, count on 4 to 6 m³ of dry wood. If you burn more often or live in a less well-insulated house, that rises to 8 to 12 m³ or more.
Which wood gives the most heat?
Oak, beech and ash are the top choices: dense wood that burns long and evenly. Beech sits around 2000 kWh per stacked cubic metre. Birch burns nicely and smells good, softwood is mainly suited as kindling because it is lighter and spits more.
Ready to get started yourself? A wood store is one of those jobs that pays you back for years in dry, warm wood.
At www.fredsdiyplans.com you will find clear build plans and step-by-step designs, so you start right away with the correct dimensions and materials. Measure, saw, stack and enjoy your fire. Good luck with the build!