Round Logs

Unique Design

1. Accurately machined taking into account the core to ensure straightness of the log.
2. Edges of the log compress, forming a tight seal.
3. The internal "locks" compress under the dead load to form three sealed chambers.
4. Inside edges of the groove designed to fit the log circumference.
5. Logs are moved during production on the flat surface to prevent damage to the grooved joints.
6. Insulation material applied (yellow) to eliminate air and moisture movement through the wall.
7. The accuracy of the wall diameter plays a key role in the thermal stability of the wall.
   

Square Logs

Precision

1.   Laminate sections are cut along the core and glued under pressure forming a joint stronger than the timber and reducing the likelihood of cracks.
2. Milled tongue and grooved joints provide strength and stability to the structure.
3. This method of joining leaves a neat line externally and internally, insulation strips are inserted to prevent the movement of air and moisture.
4. The angles ensure water runs off quickly on the external walls.
5. The thickness of the log affects the durability and thermal stability of the house.
   
6. The dead load of the building compresses the insulation and T & G joints thus ensuring stability, airtightness and movement of moisture - characteristic of a Log House.
   

Production

Square Logs

Essentially, every stage of manufacture takes place within the control of Ritsu - the CNC machinery selects logs to ensure the most economic output and to minimise waste.

The system can cater for all normal jointing methods used in Ritsu buildings and provision is made for fixing of electrics and plumbing. All joints and corners are drilled.

Once complete all logs are treated and once dried, packed and labelled for accurate on site erection.

City Corners

Planning

Ritsu's first step to revolutionising the log cabin began with the square log in 2004 - it created greater design freedom but still used design principles from the traditional log cabin with castellated corners and internal walls.

For projects in cities and indeed, here in the UK outside of the leisure sector this form of architecture might cause planning issues, certainly for homes using round logs. Enter the "City Corner", designed to make lines cleaner, paving the way for successful planning as well as initiating another avenue for design differential whilst maintaining a weathertight structure.

Take a look at Marvi, Greg and Gregor - examples of the system in use.

Thermal Capacity

Warm in winter, Cool in Summer

The term "Thermal Mass" is often used to extol the virtues of masonry and concrete homes they tend to elaborate on the virtues of these materials over timber.

Technically, there is no such thing as material thermal mass - the term more accurately describes a process, thermal capacity is a more apt description for a given material.

So instead of "thermal mass" let us use heat capacity per unit mass, here timber beats brick, concrete, plaster and stone. This means it is a better store of energy and it does so using captured carbon dioxide present at the time of felling and using less embodied carbon dioxide during production than any other building method - kinder to the environment then.

Insulation

Performance with Value

Timber has a thermal conductivity that is some 12 times lower than concrete, this means that it serves as a regulator of the climate (temperature & humidity) inside the building but sometimes on its own this is not enough.

When insulating a timber building it is important to use organic materials as these help maintain better control over humidity, what then are the options?

Cellulose Wool is a good insulator, helps to control humidity, is fireproof and a good acoustic insulator, it is also recyclable.

Rock Wool - is derived mostly from stone whose volume is about 95% of the fill making it a good insulating material. Allowing the movement of air it allows the building to breathe healthily, has high fire resistance and good acoustic performance.

Cork - like the alternatives listed above enjoys the same characteristics when used as insulation in a timber building, its natural, fireproof and entirely recycable.

A well insulated base and roof , energy efficient windows and doors which are factory fitted and triple glazed, will help to reduce heating costs, noise and Co2 creating a healthy living environment.

Behaviour in Fire

Are log homes at more risk of fire?

Massive wood – such as the logs used in the construction of Ritsu Timber Log Buildings, are inherently more resistant to the spread of fire and in many respects better than some methods of construction used in house building, timber frame, commonly used in self-builds for example.

Why? There are several reasons as to why timber is reassuringly better at resisting the spread of fire and its consequences.

The timber used in your log building comprises around 15% water upon leaving the factory, so before the combustion process can begin this water must first evaporate.

When exposed to flame, the surface of the timber will char, this process creates a natural barrier to the spread of fire as the charcoal layer formed offers much lower thermal conductivity so preventing the undamaged timber from becoming hotter.

The massive logs used in Ritsu timber log buildings sees only the external surfaces showing damage, the structure will in most cases survive intact and give time to occupants to escape safely. A timber frame building will, due to the smaller sections of timber used, generally suffer structural collapse if the source of the fire is not tackled in time. Similarly, homes constructed from lightweight gauge steel will experience collapse as steel starts to lose most or all of its structural integrity with temperatures as low as 500 degrees C.