Barns are timber framed structures, similar to houses and even wooden boats. The traditional method of building was developed in Europe in the medieval period and can be seen at its most spectacular in the structure of the great cathedrals.
Timber frames are joined together in such a manner that the whole structure is stronger when the frame is complete. “Posts” (large timbers often 8 inches square) are connected with mortise and tenon joints pinned with wooden pegs called “treenails” (pronounced trunnels) to make “bents” (the individual frames that form the basic structure). These are raised onto “sills” (these form the outer edges of the floor joists) and are joined together in the process forming a roof of rafters and purlins. Often the major joints are complex and ingenious feats of architectural carpentry.
Since each part of the structure is reinforced by the others, there is considerable strength and some redundancy in the frame. This means that if a part is damaged or fails the forces can be redistributed elsewhere without the whole building falling. This may be bend out of square or deform the barn. Barn repair often involves straightening the frame and making sure the whole is structurally sound.
The integrity of the frame is paramount in maintaining a strong building. Looking after a barn means keeping the frame in excellent condition.
Water is the enemy
When wood becomes wet, it loses its strength, swells and eventually rots. Every part of the building needs to be protected from rain and water in the ground. Frost damage is a particular concern with foundations. This means you must maintain a good roof, secure windows, doors and siding and a dry foundation. Prevention is better than a cure and caring for a barn means ensuring that the elements are kept out of the building.
Looking After The Barn
At least once a year you should make a careful inspection of the barn and its surroundings. Check that the roof is secure, that the door and windows work and that the siding is keeping the weather out. Temporary repairs should be only temporary. Leaving a problem with a quick fix is just storing trouble for some time later on. Call in the a specialist if you have any concerns and do it early, before trouble becomes expensive.
When you check the timbers use a flashlight to see in dark corners and an awl to probe for soft timbers which can lead to frame failures. Look for changes of color in the wood, this can indicate wet or infected areas that may need attention.