Your log cabin can last a lifetime, but its really important that it sits on a solid foundation. The only way to be sure that there will be no settlement in your log cabin over the years, is to put in a flat slab foundation. Building a log cabin on a set of piles or strip foundations is over complicated and costly.
Log cabin foundations - get it right
I have often heard the stoy that a few years ago there was a very good carpenter in West Munster who was hand-building bespoke design log cabins. He was doing a beautiful job, using the best of timber and putting the finest care into the construction of the cabins. They were a sight to see when they were first built. Unfortunately, this builder did not have the correct base structure. He built his cabins on an array of blocks which are not property footed. Over a period of time the blocks shifted as the log cabins settled. This led to severe structural deterioration of the cabins and of course, the customers were very unhappy. The carpenter was soon out of business.
How to build a log cabin foundation
Any reasonably competent builder will be able to build the base for your log cabin. Your base needs to be level and square and to specific dimensions which we will supply to you. Your base will be be 10 mm shorter than the cabin on each edge. Your cabin will therefore overhang the base by 10 mm all round. We also run a throated sill all around the foot of the cabin to throw water away from the base. This means that water will not pool underneath the cabin. This ensures that there is no opportunity for rot to start developing in the base timbers.
You will need to put a Radon barrier and venting system beneath your base. Again, this is something your builder should be very familiar with. We will supply a damp proof course which goes onto the surface of the base.
Along with the base dimensions, we will also supply you and your builder with detailed drawings of the cabin itself, so that you can decide where you want to locate all inlet and outlet pipes, for water and sewage.
Log Cabin Foundation Specifications
For a standard, single storey cabin, we require a base 6 inch 804 hardstone and 5 inch concrete. (30-33 N concrete.)
Foundations for smaller single room log cabins
If you're building a single room cabin, less than 25 square metres, you can place this on blocks. You will need rows of blocks, maximum one metre apart. On top of this, you will need lengths of 4" x 3" treated timber, at 800mm centres, running perpendicular to the rows of block. On top of this, we need a marine plywood platform to the dimensions required. The funsction of the plywood is to support the under floor insulation. This platform needs to be level and square.
Log Cabin Foundation Drawings
We will supply you with drawings of your cabin so that you can determine where you want to bring in water and sewerage lines. If you have any questions about any of these technical details, be sure to give us a call.
Or you can discuss any of these issues with our teams around the country
Fergus and Valerie in Tullow, Co Carlow (05991 81039)
Conor in Boyle, Co Roscommon (086 87 0429)
Donal in Carrigaline, Co Cork (087 6464 280)