Home and Building, Volume 18 Number 1 (June 1955)
Winter Repairs — Check that Dry Rot
Check that Dry Rot
Dry-rot can do serious damage to a house in a very short time. It is difficult to detect until it has been present for a long time and difficult to eradicate once it has been detected.
Dry rot is a fungus and will flourish only in an atmosphere which is warm and moist. If your house seems likely to be a favourite hunting ground for the fungus be doubly careful in your checks. Even if you remove all the infected wood remember that the conditions which brought about the damage still remain — so see what you can do to improve ventilation and drainage.
First you must test for dry rot. Remember that infected wood, when you tap it, will give a dull sound, unlike the healthy ring given by good timber. If the wood is badly infected you will find cracking of the exterior and a dusting of dry wood underneath the infected portion.
To cure it you must cut away. Dry rot runs further on the inside of the wood than it does on the outside so you will have to cut away a portion of the healthy wood surrounding it. Cut the new portion of wood to fit the gap you have made and pin it into position. Your actual method of securing the new wood to the old will depend on the size of the job and the position of the work. Give the entire surroundings several coats of a strong creosote solution before putting the new wood into position and then keep up the treatment for several more weeks.
Sometimes you will find it impossible to cut away the infected wood. If this is so you will have to treat it by soaking with creosote, zinc chloride or corrosive sublimate solution. Remember that these last two chemicals are extremely poisonous and you must use great care when applying them.
To be really effective the solution must soak right into the centre of the wood. To achieve this one or two holes bored with a fine drill will facilitate entry into the wood by the solution.
Even though you take great care with the solutions you are putting on don't make the mistake of forgetting that the brushes will still hold an extremely poisonous quantity. They should be left to soak in frequent changes of water which should be put down the drain.