How much does it cost to fix extensive water-damaged drywall in a North York townhouse after a pipe burst?

Fixing extensive water-damaged drywall in a North York townhouse after a pipe burst typically costs between $3,000 and $12,000 depending on the number of rooms affected, whether the damage spans multiple floors, and whether mould remediation is required. For a single room with moderate water damage, expect $1,500 to $4,000. If the burst pipe affected two or three rooms or caused water to flow between floors, costs escalate quickly to $6,000 to $12,000 or more for the drywall scope alone.

The most critical thing to understand about water-damaged drywall is that it cannot be dried out and reused. Once gypsum board absorbs water, the core loses structural integrity — it becomes soft, crumbly, and permanently weakened. Equally important, wet drywall becomes a breeding ground for mould within 24 to 48 hours in Toronto's climate, particularly during the humid summer months when indoor temperatures accelerate mould growth. All water-damaged drywall must be cut out and replaced, not patched over or painted.

The repair process starts with water extraction and drying, which is typically handled by a restoration company before the drywall contractor arrives. Industrial fans and dehumidifiers run for three to five days to dry the wall cavities, subfloor, and framing. This step costs $1,000 to $3,000 depending on the extent of the water intrusion, and it is essential — installing new drywall over damp framing guarantees mould growth inside the wall cavity.

Once the structure is dry, the drywall scope breaks down as follows. Demolition and removal of water-damaged drywall runs $1.00 to $2.50 per square foot, including disposal. North York townhouses built in the 1970s through 1990s typically have standard 1/2-inch drywall on walls, which costs $14 to $20 per 4x8 sheet to replace. If the water damage affected a bathroom or kitchen, you will need moisture-resistant green board ($20 to $28 per sheet) or mould-resistant purple board ($24 to $32 per sheet) for the replacement. Hanging new drywall costs $2.50 to $4.00 per square foot for walls, and taping and finishing to a Level 4 paint-ready standard adds $2.00 to $3.50 per square foot.

Pipe bursts in multi-level North York townhouses create a particularly challenging repair scenario because water travels downward through the building — a burst pipe on the upper level can damage the ceiling below, the walls on the main floor, and even reach the basement. Ceiling drywall replacement runs $3.50 to $5.50 per square foot for hanging and $2.50 to $4.00 per square foot for finishing, making it the most expensive surface to repair per square foot. If water travelled between floors, the subfloor, joists, and insulation between levels all need inspection and potentially treatment before new drywall goes up.

Mould is the hidden cost driver. If the pipe burst was not discovered immediately — for example, a slow leak behind a wall or a burst that occurred while you were away — mould may have already established itself in the wall cavity, on the framing, or behind adjacent drywall that appears dry from the surface. Professional mould testing costs $300 to $500 and is strongly recommended for any water damage that was not addressed within 24 hours. If mould is found, remediation by a certified professional adds $2,000 to $6,000 depending on the extent of contamination. Under Ontario regulations, mould remediation for areas larger than 10 square feet should be performed by qualified professionals following industry-standard protocols.

Insurance considerations are important for North York homeowners. Most home insurance policies cover sudden pipe bursts (but not gradual leaks or maintenance failures). Document the damage thoroughly with photos before any demolition begins. Your insurance adjuster will want to see the extent of the water damage, and your drywall contractor should provide a detailed, itemized quote that separates demolition, materials, labour, and finishing costs. Many restoration companies and drywall contractors in the GTA work directly with insurance adjusters and can help navigate the claims process.

Here is a practical budget range for common pipe burst scenarios in a North York townhouse: a single bathroom with wall and ceiling damage, approximately $2,000 to $4,500; a bathroom plus the ceiling below it, approximately $3,500 to $7,000; multiple rooms across two floors with mould remediation, approximately $8,000 to $15,000 or more.

Do not attempt extensive water damage drywall repair as a DIY project. Beyond the physical scope of the work, proper assessment for hidden moisture and mould requires professional equipment (moisture metres, thermal cameras), and improper repairs can lead to mould problems that cost far more to address later. Get matched with a drywall contractor experienced in water damage restoration through Toronto Drywall Installers — our service is free.