In short
- Health Canada recommends 30% to 35% indoor humidity in winter and below 50% in summer.
- Carrier's Canada guide: bypass $400–$800 installed, fan-powered $500–$1,000, steam $1,200–$2,500.
- One Ottawa firm lists bypass models at $500–$1,000, fan-powered at $800–$1,500 and steam from $1,500 installed.
- City water is very soft, about 30 mg/L; Ottawa's well systems run 200–350 mg/L, which matters for steam units.
Typical prices in Ottawa
| Job | Typical range | Notes |
|---|---|---|
| Bypass humidifier, installed | $400–$800 | Carrier Canada guide |
| Fan-powered humidifier, installed | $500–$1,000 | Carrier Canada guide |
| Steam humidifier, installed | $1,200–$2,500 | Carrier Canada guide |
| Bypass models | $500–$950 and $500–$1,000 | One Ottawa firm’s published list, range per model |
| Fan-powered model | $800–$1,500 | One Ottawa firm’s published list |
| Steam model | From $1,500 installed | One Ottawa firm’s published list |
| HVAC labour, Ottawa | $75–$150 an hour | HomeStars Ottawa page; service visits are priced after a look at the job |
Sources. Carrier Canada, Whole House Humidifier Costs, seen 29.10.2026. One Ottawa firm’s published list: bypass model, $500–$950, bypass model, $500–$1,000, fan-powered model, $800–$1,500, steam model, from $1,500 installed, seen 29.10.2026. HomeStars, How Much Does HVAC Cost in Ottawa?, published 30.06.2026, seen 29.10.2026. Humidity: Health Canada, Relative humidity indoors: factsheet and NRCan, Heating with Gas, 2012 edition (PDF), seen 29.10.2026. Water: City of Ottawa, Drinking water quality and safety, seen 29.10.2026. Equipment: Aprilaire, Humidifiers Owner’s Manual, models 350 to 700M and Aprilaire, Steam Humidifier 800/800LC specification sheet, seen 29.10.2026. Rules: ESA, Finding the right contractor and Ontario, guide for home renovation businesses, seen 29.10.2026.
The target, and does the house need one
Health Canada says indoor humidity can fall below 30% in winter, bringing cracked skin, eye irritation, static sparks and shrinking wood floors. It recommends 30% to 35%. Above 55%, moisture condenses on windows, foundation walls and pipes.
Measure first: a hygrometer from a hardware store gives the reading. NRCan’s Heating with Gas booklet says air leaks feed winter dryness and that most draftproofed, insulated houses get enough moisture from cooking and bathing. A drafty older house reading 20% makes the case; a tight newer one at 35% may need none.
One maker’s table lowers the target as it gets colder outside: 35% at about -7°C, 25% at about -18°C, 15% at about -29°C. A control with an outdoor sensor makes these changes on its own.
Bypass, fan-powered or steam
Bypass. Mounted on a duct by the furnace, it sends warm supply air through a wet pad and back to the return. It works only while the blower runs.
Fan-powered. Same pad, plus its own fan. Carrier rates its fan-powered and bypass models at up to 17–18 gallons a day.
Steam. Electrodes boil water in a canister and the steam goes into the duct. Carrier rates its steam model at up to 34 gallons a day. One maker’s sheet lists 11.5 to 34.6 gallons a day.
Pad units send a small steady stream of water to a drain while running, which flushes minerals away. Every type needs a water line, a drain route and a control.
Heat pump houses
Evaporating water takes heat. One maker’s manual says hot supply water, 60°C at most, is required for its pad units in heat pump and air handler applications. A steam unit boils its own water. With a heat pump or a hybrid setup, say so in the request.
City water or a well
The City lists its central supply at about 30 mg/L hardness, very soft. Its well systems run harder: Carp and Vars 200 mg/L, Richmond West and Munster 285, Kings Park (Richmond) and Shadow Ridge (Greely) 350.
For pad units, one maker says the pad lasts about the same on hard or softened water. For steam, hardness picks the model: one maker recommends a low-conductivity unit for naturally soft water like the City supply, a standard one for harder water, and says the low-conductivity unit fails on softened water. Name your water source and any softener.
What moves the price
Carrier puts a whole-house install at $500–$2,000 or more, with labour about half. The spread comes from:
- Type. Steam costs most, then fan-powered, then bypass.
- Ducts. Older systems may need duct changes, Carrier notes.
- Water and drain. A hot water line, a long drain run or a condensate pump add parts and time.
- Power. A steam unit runs at 120, 208 or 240 volts and 11.5 or 16 amps. Carrier notes that some homes need extra electrical work, which adds to the cost.
- Labour. HomeStars puts Ottawa HVAC labour at $75–$150 an hour, about $110 on average.
What the quote should list
Make, model, type, daily output, and whether the control reads outdoor temperature. Then separate lines for mounting, the water connection, the drain route, the control, electrical work and HST.
ESA says only a Licensed Electrical Contractor may do electrical work for hire in an Ontario home, and that whoever does it files the notification before work starts. Ontario requires a written agreement for jobs over $50, and an estimate in it can be exceeded by 10% at most unless you sign a change. Replacing the furnace too? Ask for the humidifier as its own line.
Upkeep through the season
One maker’s manual calls for a new water panel at least once a year, a yearly look at the tray above it, and the bypass damper closed for summer. Its steam canister lasts about a season, less with hard water, and a light comes on when it is due. The company can do this at the yearly furnace visit. If windows still fog with the humidifier turned down, Health Canada points to exhaust fans and ventilation; say so in the request.
Who handles your request
Ottawa Heating Desk passes your request to one independent local heating company. That company calls you back, looks at the furnace, water and drain, prices the humidifier or its service, and does the work.
Questions to ask the company
- Which type and model do you suggest for this house, and what daily output does it have?
- Will it run on hot or cold water, and where will the drain line go?
- Does the control read outdoor temperature?
- For a steam unit, who does the electrical work, and will an ESA notification be filed?
- What does yearly service cost with the pad or canister, and can I see the total with HST in writing?
Have this ready for the call
- A photo of the furnace or air handler rating plate and the ducts around it
- What heats the house: gas furnace, heat pump, or both
- Your water: City supply, a municipal well system or a private well, and any softener
- Where the nearest floor drain or condensate pump sits
- A hygrometer reading, and whether windows frost on cold mornings
Questions people ask
What humidity should an Ottawa house hold in winter?
Health Canada recommends 30% to 35%. Below 30% it links dry air to skin and eye irritation and static sparks; above 55% it warns of mould and condensation on cold surfaces.
My windows frost over on the coldest mornings. Is the setting too high?
Often, yes. Health Canada says a house may not tolerate more than 30% in very cold weather and suggests less humidification on those days. Ask whether your control adjusts for outdoor temperature.
How often does a humidifier need service?
One maker says its evaporative pad, the water panel, should be changed at least once a year, and its steam canister, per the steam unit’s spec sheet, about once a season. The manual adds that your heating contractor can service the humidifier during the furnace visit.
Is a steam humidifier worth the higher price?
Carrier says steam units give the highest output and the most precise control. They cost more to install, need their own power supply and a canister about each season, so compare both types over several winters.
Can I add a humidifier when I replace the furnace?
Yes. NRCan’s Heating with Gas booklet lists humidifiers among the extra equipment a replacement estimate should itemize. Ask for it as a separate line.
