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Vinyl siding replacement in Thornhill typically costs $6,000 to $18,000 for a standard home, depending on house size and the product chosen. Fiber cement siding (such as Hardie board) runs $12,000 to $30,000 due to higher material and labour costs. Wood siding can range widely. The total cost includes removal of old siding, installation, trim work, and waste disposal.
Vinyl siding typically lasts 20 to 40 years with minimal maintenance. Fiber cement siding can last 30 to 50 years and holds up well against Thornhill's freeze-thaw cycles. Wood siding requires more regular painting or staining and typically lasts 20 to 40 years depending on maintenance. Choosing the right product for your region is as important as the installation quality.
Watch for warping, buckling, cracks, holes, or sections that have pulled away from the wall. Fading or chalking paint, rising heating and cooling bills, and moisture or mold on interior walls near exterior surfaces can indicate that siding is no longer performing. A professional inspection can confirm whether repair or full replacement is warranted.
Siding replacement typically does not require a permit in most Thornhill municipalities unless structural changes are involved or the work is part of a larger renovation project. However, requirements vary, so confirm with your local building department or ask your contractor to check. Some warranty programs also require installation by certified contractors.
Ask for proof of liability insurance and WCB/WSIB coverage. Request a written quote specifying the siding product, manufacturer, warranty terms, and what is included in the price. Ask whether old siding will be fully removed before installation (overlaying over damaged siding is a red flag). Check that all penetrations such as outlets, vents, and windows will be properly flashed and caulked.