Cubist
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- Shropshire/Herefordshire Border
Have you noticed whether the joints between the posts and beams of your house are no longer tight and that in some instances large (a centimetre or so) gaps have formed between them?
It will be no surprise to many but the shrinkage of these timbers, which may have been cut up to 500 years ago, is still going on. The shrinkage never actually stops and in fact the timbers will be subjected to both expansion and contraction throughout each year and differentially in each timber depending on its placement in the building and other factors.
Even the smallest gaps between the post and beams can be a source of future problems for the frame. Rainwater, even un-driven, can find its way into the joints and far below the surface where it can induce or contribute to rot. You can help to significantly reduce the risk and extent of the potential damage by making sure, for yourself and future generations of owners, that even the seemingly tight seams are closed to the weather as far as possible. Caulking cotton or oakum can be hammered into the joints to close them to the weather. Oakum is best used for gaps of a centimetre or more and caulking cotton can be twisted or stranded by hand to make larger or smaller strands as needed for for narrower gaps. Oakum contains Stockholm Tar oil but Calking Cotton is dry; if you use this its sensible to apply some linseed oil after installation to help it resist rain incursion.
It will be no surprise to many but the shrinkage of these timbers, which may have been cut up to 500 years ago, is still going on. The shrinkage never actually stops and in fact the timbers will be subjected to both expansion and contraction throughout each year and differentially in each timber depending on its placement in the building and other factors.
Even the smallest gaps between the post and beams can be a source of future problems for the frame. Rainwater, even un-driven, can find its way into the joints and far below the surface where it can induce or contribute to rot. You can help to significantly reduce the risk and extent of the potential damage by making sure, for yourself and future generations of owners, that even the seemingly tight seams are closed to the weather as far as possible. Caulking cotton or oakum can be hammered into the joints to close them to the weather. Oakum is best used for gaps of a centimetre or more and caulking cotton can be twisted or stranded by hand to make larger or smaller strands as needed for for narrower gaps. Oakum contains Stockholm Tar oil but Calking Cotton is dry; if you use this its sensible to apply some linseed oil after installation to help it resist rain incursion.