Chimney
Chimney Chase Cover Replacement in Ontario
Chase Cover Purpose
A chase cover sits over the top of a framed wood chase that encloses a factory built metal fireplace chimney, sealing around the pipe while shedding rain and snow off the structure. Unlike a masonry crown, which is poured concrete, a chase cover is a sheet metal pan, and galvanized versions common on older builds corrode faster than other metal options under repeated Ontario freeze thaw cycles. A flat or improperly sloped cover lets water pool on top instead of draining off, which speeds up corrosion and can eventually let water through the seams.
Once a chase cover fails, water runs down into the wood framing of the chase, and the damage often shows up later as stains on a ceiling below. Because the chase is framed and sided like the rest of the house rather than built from brick, repairs need to respect that construction. A chase cover and a masonry crown solve the same water shedding problem with different materials, and parts made for one do not fit or seal on the other. HeatNest measures the chase, fits a custom cover with the correct slope, collar and drip edge, and checks the siding and storm collar seal while the cover is off.
Service Inclusions
- ✓ Custom sized covers
- ✓ Rust & leak repair
- ✓ Storm collar check
- ✓ Chase siding review
Typical price range
$2,500 to $6,000
Typical Ontario price range before tax. Your actual price depends on your equipment, parts and access, and is confirmed after we assess the job.
Get a tailored estimate →Signs Of Cover Failure
Rust spots or holes in the cover
Corrosion through the metal panel is a direct path for water into the chase below, even before leaks are visible inside.
Standing water or a dished center
A cover that has sagged in the middle traps water instead of shedding it, accelerating rust at the lowest point.
Water stains on the ceiling below
Leaks through a failed chase cover often travel down framing before showing up as a stain well away from the chase itself.
Loose or missing storm collar
The collar seals around the metal flue pipe where it passes through the cover, and a gap there lets water in even with a sound cover.
Cost Factors For Replacement
Chase size
A larger chase top needs more material and a bigger single piece or seamed cover, which affects fabrication cost.
Metal choice
Stainless steel or heavier gauge galvalume is specified in place of standard galvanized steel for chases with higher moisture exposure.
Related siding or collar repair
Rotted siding or a failed storm collar found during the job adds to the scope beyond the cover itself.
Replacing a failing chase cover before it leaks protects the wood framing and interior ceilings a damaged cover would otherwise expose to water. A properly fitted, correctly sloped cover avoids the larger cost of repairing rotted framing after a leak has gone unnoticed for months.
Replacement Process Overview
- 01
A technician measures the chase top precisely
Noting the flue pipe location, existing slope and the condition of the siding where it meets the cover.
- 02
A new cover is fabricated to fit the exact chase
Dimensions, with a slope built in so water sheds rather than pools on top.
- 03
The new cover is fitted with a storm collar sealed
Around the flue pipe and a drip edge that carries water clear of the siding.
- 04
Before finishing, the siding around the chase is checked for related damage
And the full perimeter seal is confirmed watertight.
Roof Access Precautions
Chase cover replacement is roof level work, so HeatNest handles the measurement, fabrication fitting and installation without asking a homeowner to access the chase top from a ladder. Because the chase is framed with wood rather than masonry, crews check for rot or water damage beneath the old cover before fitting the new one, since a sound looking cover can sit over deteriorated framing. The flue pipe and storm collar are handled carefully during removal so the venting connection stays intact and sealed throughout the job. If birds or other wildlife have nested in the chase opening, the old cover is left in place until the animals have vacated or been removed by a wildlife professional, rather than sealing them inside.
Custom Fabrication Standards
HeatNest fabricates chase covers to the exact dimensions of your chase rather than fitting a generic panel, with the slope, collar and drip edge built to shed water from day one.
Custom fit, not generic
Each cover is measured and fabricated to the specific chase rather than adapted from a standard size that may not seal well.
Correct slope built in
Covers are formed with a slope so water runs off instead of pooling and accelerating corrosion at the center.
Framing checked, not assumed sound
The chase structure beneath the old cover is inspected for rot before the new one goes on, not just the metal itself.
Questions About Chase Covers
+What's the difference between a chase cover and a chimney crown?
A chase cover is a metal pan over a framed wood chase on a factory built fireplace, while a crown is poured concrete on a masonry chimney. The two are not interchangeable.
+Why does my chase cover corrode?
Standard galvanized steel corrodes faster than stainless or galvalume options under Ontario weather, especially if the cover is flat or dished and holds standing water on its surface.
+Can a leaking chase cover damage more than the chase?
Yes. Water that gets past a failed cover can travel down framing and show up as stains on ceilings or walls well away from the chase itself.
+Should the storm collar be replaced with the cover?
If the collar is loose, rusted or no longer sealing tightly around the flue pipe, replacing it along with the cover closes off that leak path.
+Is a custom cover necessary or can I use a standard size?
Chase dimensions vary enough that a standard size often does not seal properly at the edges, so HeatNest fabricates each cover to the measured chase.
+How do I know if the framing underneath is damaged?
Soft wood, discoloration or a musty smell near the chase when the cover is removed indicates water has already reached the framing beneath it.
Maintenance Between Service Visits
Wind driven rain can work into small gaps around
An aging collar or seam well before a full leak develops.
A chase cover and a masonry crown solve the same problem differently, and parts made for one don't fit
Or seal properly on the other.
Water travels along framing
Before it shows up as a stain, so a mark near the chase is worth investigating promptly.
Service Coverage Area
HeatNest replaces chase covers on factory built fireplace chimneys for homeowners across Ontario, fitting custom metal covers sized to each chase rather than generic panels.
Acton · Adjala Tosorontio · Ailsa Craig · Ajax · Angus · Arva · Aurora · Aylmer · Ayr · Barrie · Bolton · Bowmanville · Bradford · Brampton · Brantford · Brooklin · Burford · Burlington · Caledon · Cambridge · Clarington · Collingwood · Courtice · Delaware · Dorchester · Dutton · East Gwillimbury · East York · Enniskillen · Erin · Etobicoke · Exeter · Fort Erie · Georgetown · Georgina · Glencoe · Grimsby · Guelph · Halton Hills · Hamilton · Hensall · Ilderton · Ingersoll · Innisfil · Keswick · Kilworth · King City · Kitchener · Komoka · Lincoln · London · Lucan · Markham · Midland · Milton · Mississauga · Mitchell · Mitchell Corners · Mono · Mount Brydges · New Tecumseth · Newcastle · Newmarket · Niagara Falls · Niagara on the Lake · Nobleton · North York · Norwich · Oakville · Orangeville · Orillia · Oro Medonte · Orono · Oshawa · Ottawa · Parkhill · Pelham · Pickering · Port Colborne · Port Stanley · Puslinch · Richmond Hill · Scarborough · Schomberg · Scugog · Shedden · Smithville · Springwater · St. Catharines · St. Marys · St. Thomas · Stratford · Strathroy · Sutton · Thamesford · Thorndale · Thornhill · Thorold · Tillsonburg · Toronto · Tottenham · Tyrone · Unionville · Uxbridge · Vaughan · Wasaga Beach · Waterloo · Welland · Whitby · Whitchurch Stouffville · Woodstock
What customers say about our chimney chase cover replacement
"Called in the morning, had someone here by mid afternoon. Friendly, careful and professional from start to finish."
"Great communication, I got a heads up before arrival and a clear summary of the work afterwards."
"The technician showed up on time, explained exactly what was wrong and had everything working the same afternoon. No upselling, just honest work."
Request A Replacement Quote
If your chase cover is rusted, dished or already leaking into the framing, call HeatNest at (289) 801-7262 to get a properly fitted replacement before more damage spreads.