Water leaks and poor ventilation leading to condensation are the main roof defects which give rise to a variety of fungi moulds and insect attacks.
Mold on roof trusses.
Skips a few trusses and reappears on the next panel or two.
Mold on attic sheathing.
A 10 x 10 area of plywood has been removed to provide air into this area.
Kshepard kenton shepard cmi june 18 2009 1 47am 5.
If the wood used in trusses is kiln dried the moisture content is equal to or less than 19.
This occurs when the temperature of the sheathing drops below the dew point creating a thin layer of moisture on the substrate.
Mold growth on attic roof sheathing is a common issue in cool climates such as the pacific northwest.
Re roofing with lining lining papers sarking roofing felt can cause severe mold growth and rot due to reduced ventilation.
Fact mold on the surface of lumber does not cause rotting or otherwise affect the strength of wood framing.
This growth will cease once the moisture content drops to 19 or less.
If that s mold and it looks like mold unless it s provided with enough moisture to start reproducing approx.
Cleaning mold from wood trusses and cross bracing.
The roof has baffles at alternating thusses soffit and ridge vents.
Mold is a symptom of high moisture which if allowed to exist for prolonged periods can be damaging to any structure and will promote the development of wood decay fungi.
In the vast majority of cases the mold growth is caused by condensation.
But outdoor heavy duty cleaning usually calls for more heavy duty mixtures such as tsp and chlorine bleach see the tsp page for more details or specialty additives such as jomax from rustoleum which combines a cleaner with a bleach activator.
At the south end of the roof the ridge changes direction causing an overlay condition.
You can effectively kill mold on wood in your attic using moldstat mold killer by soaking the mold growing on the trusses and plywood and allowing it to stay wet for at least 10 minutes then air dry.
If you ve had experience with mold and mildew in the home you know the best mildew remover is chlorine bleach.
Mold usually causes a musty odor and may cause staining that may be black brown gray white yellow or green.
The black mold is on the first 3 truss panels.
In an area of high levels of mold growth or moldy dust and debris the irregular surfaces formed by wood trusses and also by older wood cross bracing between floor joists prevents thorough cleaning of surfaces and creates many dust collection points.
If the mold growth is thick may need to soak the trusses and plywood.
20 in the host material it will not release spores.
The mold killer solution can be applied using a pressurized sprayer or for deeper penetration the fogmaster mold fogger.