Why a dry log store earns its keep

There is nothing quite like the sight of a well-stacked log store at the end of a country garden, roof beaded with rain, ends of the logs facing out like rows of coins. It looks reassuring, and it is: a proper store turns a pile of damp timber into fuel that lights easily, burns hot and leaves little behind but ash. Get it wrong, though, and you end up with a soggy heap of bark, mould and disappointment.

Wet wood is not simply harder to light. Green or rain-soaked logs can hold more than half their weight in water, and burning them wastes most of the heat driving that moisture off as steam. Worse, the tars and creosotes that condense in a cool flue coat the chimney and increase the risk of a chimney fire. Seasoned firewood should sit somewhere below 20 per cent moisture, and a log store that breathes is how you get there.

Raise the base clear of the ground

The single most common mistake is building a store straight onto soil, gravel or a concrete slab. Ground contact is where rot begins, and it begins quietly. Even a slab will pull damp upward through capillary action, and the bottom layer of logs will quietly darken, soften and grow a beard of white mould while the rest of the stack looks perfectly fine.

Lift the whole stack at least 100mm, ideally 150mm, above the ground and keep an open void beneath it so air can move under the logs as freely as it moves around them.

• Set the store on concrete blocks, engineering bricks or stout timber bearers laid on a firm, free-draining surface.
• Use a slatted timber pallet as the floor — the gaps let water drip straight through rather than pooling.
• Never let the pallet sit directly on grass or bare earth; give it a gravel pad or a couple of paving slabs.
• Leave the front edge of the base clear so any water blown in runs out and away rather than soaking the bottom row.

If the store stands on a slope, dig a shallow drainage channel or lay a line of gravel along the uphill side to divert run-off. A store that stays dry underneath will outlast one that does not by a decade or more.

Leave gaps between the logs

Air is the real builder of a good log store. Every gap you leave is a small chimney, and stacks that are packed tight and tidy will hold moisture in the middle for months. Seasoning is a process of evaporation, and evaporation needs moving air.

• Stack logs with the cut ends facing outward, where the air can reach the grain and draw moisture out along the length of the timber.
• Leave a finger's width of space between logs where you can, and avoid wedging them tightly to make a neat wall.
• Alternate the direction of each layer, or build in a criss-cross pattern at the corners, so the stack holds itself without needing to be crammed.
• Keep the sides of the store open or slatted; solid boards on all four sides simply create a dark, humid box.
• Split larger rounds before stacking. A log split in half dries many times faster than a whole round with the bark intact.

Leave a hand's width between the stack and the back or side walls of the store, too. Logs pressed against boarding trap damp against the timber frame.

Face the open side away from the prevailing rain

In Britain, most of our wet weather arrives on a south-westerly, so the open, working face of a log store is best turned towards the north, east or somewhere between the two. That way the wind that carries the rain hits the closed back and roof, while the logs breathe out of the sheltered side. If you are in the east of the country, or on a coastal spot where the wind has a different habit, watch which way the rain usually drives across your garden and turn the store to suit it.

The roof matters just as much as the orientation. Give it a generous overhang — 300mm or so on the open side is not excessive — and slope it gently backwards so water runs off behind rather than dripping down the front of the stack. A sheet of corrugated metal, felt shingle or slate all work well.

Shelter without smothering

The temptation in a wet spell is to throw a tarpaulin over the whole thing. Resist it. A tarp draped over the top and down the sides seals in the very moisture you are trying to shift, and you will often find condensation running down the inside of the plastic by morning.

• Cover the top only, leaving the sides entirely open to the breeze.
• If you must use a sheet, stand it off the logs with a couple of battens so air still moves underneath it.
• Keep the bottom row clear of fallen leaves, which hold damp and shelter insects.
• Rotate your stock: use the oldest, driest logs first, and top up at the back.

A store that works all year round

Fill your store in spring and early summer if you can, so the warm months do the seasoning for you, and aim to have next winter's wood put by before this winter's is burned. Freshly cut hardwood such as ash, oak or birch will want a good twelve months in the stack; softer woods dry faster but burn quicker.

Check the bottom layer every few months, especially after a long wet spell. If you find soft, dark patches or a sour, mushroomy smell, the base is too low, the gaps too tight, or the rain is getting in where it should not. Shift the stack, add another course of blocks, and let the air back in. A log store is a simple thing, but looked after properly it will pay you back every cold evening of the year.