Air Filters London
Furnace, AC and commercial HVAC filters for homes, rentals, hospitals and businesses across the Forest City – made in Brampton and shipped west along the 401.
- ✓ Made in Canada
- ✓ Custom sizes
- ✓ MERV 8 · 11 · 13
- ✓ No customs or duties
Air quality in London
London earned its Forest City nickname honestly. Mature maples, oaks, ashes and lindens shade Old North, Woodfield, Wortley Village and the streets around Western University, and the Thames River forks right beside downtown before winding through parks and floodplain woodland. That green canopy is one of the best things about living here, but from April to June it releases huge amounts of tree pollen, and late-summer ragweed keeps allergy season going until the first frost.
The city is also a major crossroads. Highway 401 runs along London's southern edge and Highway 402 branches west toward Sarnia and the Blue Water Bridge, so transport trucks pass the south and west ends around the clock. Industrial parks near the 401, rail lines through the east end and steady growth in the north and south-west all add to local dust and exhaust.
Surrounding Middlesex, Elgin and Oxford counties are farm country, with corn, soybean and wheat fields that send dust into the air at planting and harvest. London also sits in the path of lake-effect snow off Lake Huron, and when spring snowmelt leaves sand and grit on the roads, dust rises with the first dry, windy days. In recent summers, smoke from distant wildfires has drifted over Southwestern Ontario too.
London climate, homes & HVAC systems
London's climate is classic Southwestern Ontario: warm, humid summers that keep central air running from June into September, and cold winters with more snow than Toronto thanks to Lake Huron squalls. Heating season typically runs from mid-October to April. With the furnace and AC working back to back, your HVAC fan moves air through the filter for most of the year.
Homes range widely. Old North, Old East Village and Wortley Village are full of Victorian and Edwardian brick houses, many converted from boilers or gravity furnaces to forced air with tight 1-inch filter slots. Post-war bungalows and split-levels fill Westmount, White Oaks and Argyle, while Hyde Park, Sunningdale, Byron and Lambeth have newer two-storey homes with high-efficiency furnaces and 4-inch media cabinets. Thousands of student rentals near Western and Fanshawe College, plus apartment towers downtown and along Richmond Street, round out the mix.
MERV 11 year-round, MERV 13 through pollen season
MERV 11 traps most tree pollen, dust and pet dander without straining older furnaces. If anyone in the house has seasonal allergies or asthma, run MERV 13 from April until ragweed season ends in the fall.
Shop MERV 11 → Shop MERV 13 →Seasonal filter tips for London
- Spring: Change the filter as soon as the street trees bud – London's canopy releases pollen early.
- Summer: Keep windows closed on high-pollen and smoky days and let the AC filter the air.
- Fall: Put in a fresh filter after the first frost ends ragweed season and before the furnace starts.
- Winter: Lake Huron squalls and cold spells mean long furnace cycles – check monthly.
Which MERV rating is right for your London home?
MERV (Minimum Efficiency Reporting Value) measures how well a filter captures particles of different sizes under the ASHRAE 52.2 test standard. Higher numbers catch smaller particles. Most residential furnaces in Canada run well on MERV 8 to MERV 13 – here is how to choose:
| Rating | What it captures | Best for |
|---|---|---|
| MERV 8 | Dust, lint, pollen, mould spores and larger particles (3–10 microns) | Budget-friendly everyday protection, rental units, new-build dust |
| MERV 11 | Everything MERV 8 does plus pet dander, fine dust and some smoke (1–3 microns) | Most family homes, pets, seasonal allergies |
| MERV 13 | Fine particles down to 0.3–1 micron, including much of the PM2.5 in wildfire smoke | Asthma, allergies, wildfire smoke, newborns and seniors |
Not sure? Read our complete MERV rating guide. If you are moving up to MERV 13 on an older furnace, a deeper 2-inch or 4-inch filter keeps airflow healthy.
Popular furnace filter sizes in London
These sizes cover most London furnaces, from Old South century homes to new builds in the north end. Older houses with converted heating systems often need non-standard sizes, which we make to order.
How often to change your furnace filter in London
| Filter depth | Typical home | Pets, allergies or smoke |
|---|---|---|
| 1-inch | Every 1–3 months | Every 30–45 days |
| 2-inch | Every 3–4 months | Every 2 months |
| 4-inch | Every 6–9 months | Every 4–6 months |
| 5-inch | Every 9–12 months | Every 6 months |
In London, change filters at the start and end of pollen season, and more often if you live near the 401, 402 or an active construction site. See the full filter changing guide.
Air filters for London businesses & property managers
London is Southwestern Ontario's hub for health care, education and manufacturing. Large hospital campuses, research labs, long-term care and retirement homes, Western University and Fanshawe College, school boards, food processors, defence and auto-parts plants, and warehouses along the 401 all run air handlers and rooftop units that need regular filter changes.
We supply London facility teams, property managers and HVAC contractors with pleated, pocket, rigid cell and V-bank filters by the case. Student-housing landlords and apartment owners can standardize sizes across buildings and schedule deliveries before each change cycle.
- Pleated filters in 1", 2" and 4" depths, MERV 8–13
- Pocket (bag) filters, rigid cell and V-bank filters for rooftop units and air handlers
- Wire panel, HEPA, carbon and media pads & rolls
- Volume pricing, scheduled deliveries and NET terms for approved business accounts
Shipping & delivery to London
Orders to London ship for a $25 flat rate, and orders of $2,500 or more ship free. Most orders arrive in 3–9 business days.
Standard sizes are usually made and shipped within 1–2 weeks; custom sizes can take up to 3 weeks. Prefer to collect? Free pickup is available Monday to Friday, 7:00 AM – 4:30 PM at 15 Melanie Drive, Brampton. Full details are on our shipping & returns page.
Why London customers choose Canadian Air Filters
Areas we deliver to in London
Downtown · Old North · Old East Village · Wortley Village · Woodfield · Byron · Masonville · Hyde Park · Sunningdale · Westmount · White Oaks · Argyle · Oakridge · Lambeth · Pond Mills · Huron Heights · St. Thomas · Strathroy · Komoka · Ilderton
Nearby location pages: Ontario, Peel Region, York Region, Durham Region, Halton Region, Toronto, Hamilton, Kitchener-Waterloo, Barrie, Windsor, Ottawa, Guelph, Kingston, St. Catharines, Sudbury, Thunder Bay, Peterborough. Or see all locations we deliver to.
London air filter FAQ
Why is pollen so bad in London, Ontario?
London has one of the largest urban tree canopies in the province, so spring tree pollen is heavy, and ragweed follows in late summer. A MERV 11 or MERV 13 filter changed at the start of each season helps reduce what circulates indoors.
What MERV rating should London homes use?
MERV 11 suits most homes. Choose MERV 13 for allergies, asthma or smoky days. If your furnace is older, a deeper 2-inch or 4-inch filter keeps airflow healthy at higher ratings.
My Old North house has an unusual filter size. Can you help?
Yes. Older London homes with converted heating systems often have odd filter slots. Measure the slot or read the old filter's frame and browse our special sizes.
I own student rentals near Western. What should I stock?
Most landlords stock MERV 8 or MERV 11 filters by the case and change them at every move-in and mid-winter. See our bulk ordering options.
Do you ship to St. Thomas, Strathroy and the surrounding towns?
Yes. We ship to every address in London and Middlesex and Elgin counties, including St. Thomas, Strathroy, Komoka, Ilderton and Lambeth.
Does wildfire smoke affect London?
It can. Smoke from fires in Northern Ontario, Quebec and Western Canada has reached Southwestern Ontario in recent summers. Keep a spare MERV 13 filter ready and read our wildfire smoke guide.
How much does shipping to London cost?
Orders to London ship for a $25 flat rate, and orders of $2,500 or more ship free. Most orders arrive in 3–9 business days.
Can you make custom-size filters for my London home or building?
Yes. Because we manufacture in Brampton, we can build non-standard and custom sizes to order – usually within about 3 weeks. Use our custom filter form or email info@canadianairfilters.com with your dimensions and MERV rating.
Helpful air quality guides
Ready to breathe better in London?
Made in Brampton · $25 flat rate · standard & custom sizes.