Cleaning the mould without fixing the airflow just schedules the next one.
Almost always the same mechanism: warm moist household air leaks up through ceiling penetrations into a cold attic that cannot breathe, meets the underside of the roof deck, and condenses. In a Toronto January it condenses as frost. In March the frost melts.
So the order of work is fixed: remove the contaminated material under containment, clean and treat the surfaces, then air seal the ceiling and restore the soffit-to-ridge airflow, and only then re-insulate. Skipping the middle step means doing the whole job again in three years.
We are an insulation contractor. We remove contaminated material, clean and treat surfaces, and correct the cause. We do not issue air-quality clearances and we do not do structural repairs. Where the sheathing has gone soft, you need a roofer, and we will say so.
Attic mould is usually separated from the living space by the ceiling, so exposure risk is lower than mould inside the house. The larger risk is to the building: sustained moisture degrades sheathing and trusses. Treat it as a building problem to solve before it becomes a structural one.
Not if the cause is corrected. It will, reliably, if only the surface is cleaned.
No. Bleach on porous wood cleans the surface and leaves water behind. We use an antimicrobial made for the substrate.
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You get the depth, the tier, the dollar figure and the photographs, whether or not you go ahead with us.
