Gas Fireplace Installation Thornhill, Markham — TSSA-Certified
The install quality shows up in the commissioning numbers, not the showroom.
Free instant install estimate + $150 off a booked installation
What will a fireplace install cost in Thornhill, Markham?
Five questions, real Thornhill, Markham pricing. You get an installed price band including venting, gas, finishing and permit — before anyone calls you.
Gas is still the right answer for most homes in Thornhill, Markham: real heat during an outage-prone winter, no wood to store, and instant control. We install direct-vent sealed-combustion units, run the gas line, handle the permit, and hand you a commissioning sheet with the actual gas pressure and CO readings recorded.
Direct-vent done properly
Termination clearances to windows, decks, and property lines in Thornhill, Markham are code-controlled and frequently ignored by cheap installers. We plan the termination before selecting the unit.
Gas line and pressure
An undersized line starves the appliance and shows as a lazy yellow flame. We size the run to the appliance's BTU rating and verify with a manometer at commissioning.
Safety documentation
Every install leaves with a commissioning sheet: inlet and manifold pressure, spillage test result, CO reading, and the technician's TSSA number.
Fireplace Installation pricing in Thornhill, Markham
Real 2026 ranges. Your exact number is confirmed in writing before any work starts.
| Service | Typical range | Notes |
|---|---|---|
| Gas insert, existing opening | $4,200 – $6,400 | Supplied and installed |
| Direct-vent through exterior wall | $5,400 – $9,200 | Includes venting and termination |
| Gas line extension from meter | $450 – $1,600 | Distance and access dependent |
| Annual service after install | $179 – $259 | Recommended by every manufacturer |
How the visit works in Thornhill, Markham
- 1
In-home design visit
We measure the opening, check gas supply and venting routes, and confirm what your home in Thornhill, Markham can actually accept before quoting anything.
- 2
Written fixed quote
Unit, venting, gas line, electrical, finishing, permit, and disposal — itemised, in writing, before you commit.
- 3
Permits and TSSA compliance
Gas work is performed by TSSA-certified technicians and permitted where the municipality requires it. Paperwork is our job, not yours.
- 4
Installation day
Framing checks, direct-vent termination, sealed gas connection, leak test, and electrical hookup — usually a single day for a standard insert.
- 5
Commissioning and safety test
Manometer gas-pressure reading, spillage test, CO check, and flame calibration recorded on the commissioning sheet.
- 6
Handover and warranty
We show you the controls, register the manufacturer warranty, and leave the commissioning sheet, permit, and photos with you.
What Markham customers say
4.9 out of 5 from 743 reviews across the GTA. A selection relevant to this service below.
I wanted a bigger unit. They explained why it would overheat the room and recommended a smaller model — and were right.
Building would not approve gas. They framed and installed a recessed electric linear unit in a day and it looks built-in, not bolted on.
Cleaned the burner, checked the venting, and adjusted the flame. Tidy work and fair pricing, and they left the commissioning readings with me.
In-home measurement, written quote the next day, install two weeks later, and a walkthrough of the controls before they left.
Fireplace Installation FAQs — Thornhill, Markham
Are your gas technicians certified?
Yes — TSSA-certified gas technicians perform every gas connection in Thornhill, Markham, and the certification number is on your commissioning sheet.
Does a gas fireplace work in a power cut?
Millivolt and battery-ignition models do. Fan-assisted heat distribution stops, but the burner keeps running.
Do I need a permit in Thornhill, Markham?
Usually yes for new gas lines and venting penetrations. We apply, schedule the inspection, and leave the documentation with you.
How long does the install take?
One day for a standard insert; two to three for a new build-out with framing and finishing.
How much does it cost to run?
A 25,000 BTU unit running four hours a day costs roughly $30 to $55 a month at current Ontario gas rates.
Can you install in a condo?
Where the building allows a compliant vent termination, yes. We handle the property-management paperwork in Thornhill, Markham.
Book fireplace installation in Thornhill, Markham
Free instant install estimate + $150 off a booked installation — 24 hour response guaranteed.
Call (437) 475-2233