During the first year after construction, gaps can sometimes appear in the walls of a log cabin. Taking practical steps can stop them from becoming a bigger issue.
A log cabin in the garden is a great place to spend time both during the summer and winter. Plenty of homeowners purchase cabins every year and most of them are relatively problem-free. During the warmer months, a cabin is an ideal place to unwind during the evenings or use as a garden office away from the house.
However the cabin is used, we expect the structure to be solid and secure, without any gaps in the wood or fixings. Holes in the building can lead to heat escaping when the temperature drops or doors & windows not closing correctly.
Log cabins have a long lifetime and can last for over fifteen years when the timber is correctly cared for. But every year, owners of log cabins purchased within the last few years find their building beginning to show signs of wear.
Thankfully, most issues with gaps in log cabins can be treated when discovered early. Correct treatment of the log cabin during installation can prevent gaps from appearing in the first place.
Before contacting the log cabin manufacturer, be sure to understand whether the gaps have been caused by incorrect installation or treatment of the building.
Why does my log cabin have gaps?
Gaps can appear in a log cabin at any time, but they are most prominent during the first year. A building that has been installed during the hottest days of the summer or coldest days of the winter is most likely to have issues with gaps.
Both times of the year are the extremes of the environment that the timber is exposed to.
Gaps are caused by either contraction or expansion of the timber logs in a cabin. The wood can be thought of as similar to a sponge and will take on moisture depending on the environmental conditions around it.
During the winter, the timber will absorb moisture due to the damp cold conditions, causing the wood to expand slightly. In the summer, plenty of warm sunshine and dry weather results in the wood losing water content and contracting.
Movement in each log is small and unnoticeable to us. But the combined movement between all of the logs in a cabin can result in movement that causes visible gaps in the building’s construction.
Contraction or expansion?
Before rectifying any gaps, be sure to check whether they are caused by expansion or contraction. Doing so can avoid the issues appearing at the same time next year.
Contraction is typically noticed during the summer months, after a log cabin has been installed during the winter.
During a winter installation, the wood may have already expanded and taken on water from the surrounding atmosphere. This will be exacerbated if the materials have been left uncovered in a wet garden before installation.
Over the next few months as the weather gets warmer, the wood drys out, causing it to contract and shrink slightly. This results in contraction gaps in the log cabin walls during the summer months.
If the building has not been treated correctly, the gaps may start to disappear again during the winter when the wood takes on moisture.
Expansion issues are often noticed during the winter, especially if the cabin has been installed during the summer.
The moisture content of untreated wood will often be at its lowest during the summer, as the warm sunny climate keeps it down. If the moisture levels rise during a wet period, expansion occurs in the wood.
Expansion in a log cabin can also be a sign of damp and water issues. Ideally, a fully treated log cabin should be prevented from taking on much water as the wood preserver will create a waterproof coating on the surface.
Lack of wood treatment
As well as changing the appearance of a log cabin, wood treatment provides an important role in protecting the timber. Without any treatment, the wood is constantly exposed to the elements throughout the year.
The ever-changing weather and frequent rainfall, followed by dry spells can have a noticeable effect on the timber within a few months of ownership.
An untreated cabin will take on moisture from its surroundings each time there are wet conditions, causing the timber to expand slightly. Once the sun comes out, some of the moisture will be dried out, causing the wood to contract again.
The frequent movements in the wood can lead to gaps appearing in the walls. The goal is to create a waterproof coating on top of the wood to prevent the moisture levels inside from changing.
Wood treatment should also be applied to the interior of the log cabin. This will result in the wood becoming more stable and reduce any movement further. Treating the interior can also inhibit mould growth and prevent the wood from being stained.
Most log cabin manufacturers require the building to be treated correctly for any issues such as gaps to be covered under warranty.
Fixings between separate logs
The construction of a log cabin is unique to any other building, and it’s important the installer is aware of how the building assembles.
Unlike other timber constructions such as summerhouses, a log cabin is built up in layers of interlocking logs that drop into place on top of each other. The logs fit together tightly, creating a weatherproof shell.
Nails or screws are not used in the process of joining the logs together. This allows the building to move as needed throughout the year.
Gaps in a log cabin are often caused by fixings securing several logs together, preventing any movement in the wood. If the installer is a carpenter or builder that has not installed a cabin before they may incorrectly attach logs together when they shouldn’t be.
Other common examples include shelves or similar wall attachments such as electrics that are installed across multiple logs. Whether you are installing interior features yourself, or someone else is, be sure to check they are not attaching multiple logs together.
Log cabins come with detailed instruction guides for assembly, and some even provide videos. If there are sections that are unclear, be sure to contact the manufacturer for clarification before assembly.
Sometimes, extra pieces of wood are added to the construction of a log cabin which was not included by the manufacturer.
This can be a common issue when the cabin is assembled by someone that has not built a log cabin before. The design for most log cabins deliberately leaves small gaps at certain locations where they will not cause issues and remain unnoticeable.
These are expansion gaps, allowing for natural movement in the building during the different seasons of the year. Flooring typically contains a small expansion gap around the edges, allowing for different levels of movement between the floor and walls. Without a gap, ripples can begin to appear in the floor during expansion.
Small expansion gaps can also be found where different sections join together, such as near doors and windows.
Guide: How long do log cabins last?
How to fix gaps in log cabins
Gaps in the structure of a log cabin can be avoided completely with correct assembly and treatment. If the log cabin already has gaps appearing, taking remedial action can soon see them resolved.
Any gaps will be most noticeable during the first year after assembly. Once the building has settled, expansion & contraction of the timber becomes less of an issue.
Apply a wood treatment
One piece of advice we give to all garden building owners is to invest in a good quality wood treatment. This is one area where it really does pay to purchase the premium option. As well as looking great, wood treatment plays an important role in protecting the timber.
For newly purchased cabins, the treatment should be applied as soon as possible after assembly. Several coats are often required to get a high level of protection that will last for years into the future with minimal maintenance. Treating the cabin should be carried out on a dry and clear day, and the timber should be dry first.
Wood treatment creates a weatherproof seal over the timber. This prevents moisture from being absorbed and keeps the moisture content at equilibrium. Therefore contraction and expansion which can lead to gaps is minimised.
For best results, all sides of the wood should be covered and the cabin interior also painted. If small areas of unpainted wood appear after a few months, they can also be painted with the same product.
The wood treatment provides numerous other benefits as well. The coloured pigments provide UV protection, stopping the wood from turning grey or cracking. Most products are also anti-fungal, inhibiting the growth of mould and rot which can lead to damage to the timber.
Remove extra fixings across multiple logs
If there are fixings across several different logs that were not included as part of the manufacturer’s instructions, they should be removed.
The cabin does not require extra fixings, and if it did they would be included with the cabin and listed in the instructions. Any fixing that is restricting the movement of the logs could lead to gaps appearing.
Shelves and curtains etc on the inside are common examples that are added after installation. To install these correctly, ensure the brackets are only attached to a single log. Additional screws and nails where the fascia attaches can also restrict the movement of the logs.
Check for water leaks & condensation
Too much water inside the cabin can lead to the logs expanding and gaps appearing. Condensation on the windows is a telltale sign of a moisture issue inside a building. The cabin should be inspected to see if water is getting in through anywhere it shouldn’t be.
The base of a log cabin should feature a damp proof membrane. The DPM stops moisture rising from inside the base and getting trapped inside the cabin. This can be a particular problem when concrete bases are used and the surroundings are grass.
A poorly treated cabin could also have water seeping its way through the miniature gaps in the logs. To rectify this, apply several coats of a good-quality treatment.
Most leaks from rainfall appear in the roof. After it has been raining, inspect the building for any obvious signs of leaks. There may be water dripping down the wall or coming from the ceiling. The leaks can be addressed by adjusting the roof or using a small amount of wood sealant.
Guide: Can a log cabin be moved?
Gaps appearing in log cabins are most common during the first year of use. As the building goes through different seasons, the wood is affected by the changing moisture content levels in its surroundings. The gaps are fixable and preventive measures can stop them from coming back.
We first need to understand why the gaps are appearing and whether it’s due to expansion or contraction in the timber. The most common cause is untreated wood or fixings restricting the natural movement of the logs.