Barrel sauna roof: shingles, felt or metal?

A barrel without a roof covering will last a few years, but a good deal fewer. The roof is the cheapest insurance for the structure, and it is often the part with the shortest warranty, which hardly anyone asks about when buying.

Bitumen shingles

The most common choice and the most sensible one for a barrel. They are flexible, so they lay well on the curve, look natural and dampen the sound of rain.

Properly laid, they last for many years. When the time comes, replacing them is a simple and inexpensive job.

One caveat: shingles do not cope well with resin. If the sauna stands under conifers, the roof needs cleaning more often.

Roofing felt

The cheapest option and technically perfectly adequate. Less attractive than shingles and usually shorter-lived.

It suits a sauna at the bottom of the garden where looks matter little, or when the budget is tight and you would rather put the difference into a stronger stove.

Metal

Very durable and completely watertight. But it is loud in the rain, and a sauna is where you go for quiet. It tends to rain just when it is cosiest inside.

It is harder to fit to a curved shape, so it is less common on barrels than on rectangular buildings.

No covering, bare timber

You find this on the cheapest offers. Timber on the roof takes the water from above and dries slowest, so this is where the first problems show up.

If you buy a version like this, budget for a covering from the start and plan to fit it in the first season, before the wood soaks up water.

The overhang counts

The roof should project beyond the end wall on the door side. Without an overhang, water runs straight onto the door and the wall around it, which is exactly where the seal and hinges are.

It is a detail you cannot see in a catalogue photo, but after three years it makes a visible difference.

What to look for in a quote

Is the covering included in the price, or an extra?

How long is the warranty on the covering? It is often shorter than on the structure.

Does the roof overhang the door?

Is the flue passage built with a proper insulated flashing, rather than just a hole in the covering?

Check once a year

The condition of the covering at the overhang and around the flue passage. Leaks start in these two places.

Whether any individual shingles have come loose over winter.

Whether water runs off freely and does not get caught on leaves and needles.

A look from a stepladder takes five minutes. A loose shingle caught in time is a small repair, rather than replacing staves two years later.

Snow in winter

Dry snow slides off a round roof by itself. The problem is wet, heavy snow during a thaw, and then it is worth clearing.

Not with sharp tools. Use a soft broom or a push with a rubber edge so you do not damage the covering.