Log house vs timber frame house: what to choose for Batumi and Adjara

On the Adjara coast, wood lives with damp: more than 2,400 mm of rain falls in a year, and the average humidity does not drop below 70% in any month. When we weigh up a log house vs timber frame house, the first thing we look at is where the wood will end up. In a log house it is on the outside and takes the rain. In a timber frame house, built as a light frame of studs, it is hidden behind the facade and membranes.

Moisture, rot and facade upkeep

All season a log wall gets soaked by wind-driven rain and then dries in the wind. The protective finish on it fades in the sun and washes off, so a log facade has to be refinished regularly, and more often on the side that takes the rain. Miss a couple of seasons and the wood darkens on the log ends and the bottom logs.

The most vulnerable part is the bottom row of logs. It sits on a damp-proof course, and the plinth is raised high enough that splashes from heavy rain do not reach the wood. In Batumi a log house must have wide roof overhangs.

In a timber frame house the timber is covered by a windproof membrane and a facade with a ventilated air gap. Damp harms it too: water reaches the timber through a leak around a window or a tear in the membrane, and in an empty house in winter the wood takes up moisture from the air. The frame is protected against this by a vapour barrier chosen by calculation, by airing the empty house and by an inspection after every winter.

Settling and build time

For Batumi we use kiln-dried or glulam logs, because undried logs take too long to dry in humid air. Kiln-dried logs also settle a little after assembly, so windows and doors go into settling frames that let the wall move down around them. Finishing starts once the settling is over, and in the first seasons the screw jacks under the posts are adjusted and the doors are checked to see how they close.

A frame of kiln-dried timber hardly settles, and finishing can start as soon as the house is closed in. In Batumi that is a strong argument. A log house assembled in spring has to get its protective finish by September, because the rainy season then lasts until January. And while the house is settling, it is too early to move in anyway.

Seismic load and slopes

A timber house is light, and the seismic load on it is small with either option. A log wall is tied together vertically with dowels, and the house is anchored to the foundation. In a timber frame, stiffness comes from diagonal bracing and sheathing.

On a slope, both houses sit well on pad or pile foundations tied together by ground beams, without much earthwork. A timber frame is lighter than logs and needs a smaller foundation, which on a steep plot is a noticeable saving.

Log house vs timber frame house for renting out

Noise is a problem in both. A timber floor carries footsteps, and a log wall between guest rooms lets voices through unless a second layer is added. A framed partition is easier to make quiet: two layers of boarding, mineral wool inside and staggered studs for the two sides. So in a log guest house we usually build the walls between rooms as framed partitions.

Log walls in a guest room show wear. Suitcases and wet towels leave marks, and the wall has to be sanded and refinished. The repair is simple and done on the spot. Plasterboard in a timber frame house is cheaper to restore, but it dents more easily.

A guest house also raises the question of fire. A log wall is exposed on the inside, so the wood is treated with a fire retardant, and non-combustible shields are fitted next to the fireplace and the cooker. In a timber frame house the studs are hidden behind plasterboard, and that lining already protects them.

Repairs and checks if you live far away

Major repairs are harder with logs. A rotten bottom log is replaced by jacking up the wall, while in a timber frame the rotten part of a sole plate or stud is cut out and replaced.

In the estimate, a timber frame is usually cheaper at the shell stage, but it needs a facade and an internal lining. Logs cost more as a material, but a log wall is the facade and the interior at once. Compare finished houses with all the finishes in. The price of the walls alone tells you little.

A log house has little concealed work. Almost everything stays visible except the insulation between the logs and the damp-proof course under the bottom log. A timber frame house consists almost entirely of things that will be covered later, so we photograph every wall before it is boarded and put the photos in the handover file.