28mm vs 44mm log cabin walls: which thickness do you need?

Short answer: choose 28mm walls for a summerhouse or a room you'll mostly use from spring to autumn. Choose 44mm (or thicker) if you want to work in it through the winter. Thicker walls cost more, but on the same cabin the difference is usually a few hundred pounds – see the real examples below.

What “wall thickness” means

A log cabin's walls are made of solid timber boards (“logs”) that slot into each other with a tongue and groove joint – a ridge on one board fits a channel in the next – and lock together at the corners. The thickness is the width of each board. It's the main thing that decides how sturdy the cabin is and how well it holds heat, because unlike a house, most kit cabins have no insulation in the walls at all.

What each thickness is good for

• 19mm: the thinnest. Storage, a potting room or occasional summer use. (4 in our index)
• 28mm: the common entry level. A summerhouse, hobby room or a spring-to-autumn office. (14 in our index)
• 40–45mm: the usual choice for a garden office used most of the year. Stiffer walls, better at holding heat, and quieter. (63 in our index)
• 58mm and up, or insulated logs: the warmest kits. Some sellers offer walls made as a sandwich of timber and insulation. (7 in our index)

One way to compare warmth is a U-value: how much heat escapes through a square metre of wall (lower is better). Few kit sellers publish one. Dunster House does: it lists its 45mm walls at 1.93 W/m²K on pages such as the Coronet Corner Log Cabin 2.5m x 2.5m, and quotes lower figures for its insulated garden offices.

How much more do thicker walls cost?

These are the same cabin, same size, from the same seller – only the wall thickness changes. Prices as listed when we checked.

Walls aren't the whole story

Heat escapes through the weakest parts first. Before you pay for thicker walls, check:

• Glazing. Double glazing (two panes of glass with a gap) keeps far more heat in than single glazing or plastic “styrene” windows. Some cheaper cabins come single glazed, with double glazing as a paid upgrade.
• Floor and roof. Most kits have thin timber floor and roof boards with no insulation. If you'll use it in winter, plan to insulate both. Check whether the floor is even included – with some sellers it's extra.
• Roof covering. Basic roofing felt is cheap but wears out; EPDM is a rubber sheet that lasts much longer.

Our rule of thumb

For a year-round office we look for walls of 44mm or more, double glazing as standard, and a floor included in the price. Here are the cabins that meet all three. Or compare every 28mm cabin and every 44–45mm cabin.