Aluminum Siding, Capping & Eavestrough in Markham: Heritage Districts to New Subdivisions

• Markham has four heritage conservation districts: Thornhill, Markham Village, Buttonville and Unionville.
• Inside a district, the heritage permit rule covers both heritage and non-heritage properties.
• General repairs to eavestroughs and existing cladding are listed by the City as not needing a heritage permit.
• Outside the districts, Markham’s 1970s–90s suburbs and newer subdivisions are where most capping, soffit and eavestrough work happens.
• Pro Aluminum Siding provides free estimates, a written contract and a 5-year workmanship warranty, and is fully insured with WSIB coverage.

Do exterior changes in Unionville or Markham Village need heritage approval?

Yes, in most cases. The City of Markham’s heritage permit page says a permit is required before external alterations to any property inside a heritage conservation district, whether or not that particular house is considered a heritage building. That is the single most important thing for a Markham homeowner to know before calling any siding contractor.

The City sorts this work into minor and major heritage permits. Its list of minor permit projects includes “new or different wall cladding or roof treatment,” removal and replacement of windows or doors, and new or changed architectural decorations, which it spells out as verandas, trim, soffits, fascia and awnings. In plain terms: re-siding a house, swapping out soffit and fascia, or wrapping window trim in new aluminum is the kind of work the City expects to review.

There are exemptions. The same page lists general repairs to weather-stripping, eavestroughs, roofs, chimneys, fences and existing cladding as not requiring a heritage permit. Fixing a sagging run of eavestrough or patching a damaged section of existing cladding is treated differently from replacing it with something new.

What the district plans say about metal siding

The district plans go further than the permit list. The Unionville Heritage Conservation District Plan states that “the use of metal and synthetic sidings such as vinyl are not supported,” encourages owners to keep painted wood siding and replace it only when it has lost its integrity, and asks that replacement material match the original form, profile and texture. It also warns that vinyl installations can strip away cornerboards and window and door trim, which is exactly the detail that gives a village house its character.

Markham Village’s guidelines classify buildings by type. “A” buildings establish the heritage character of the district and should be conserved; “B” buildings, old or new, are considered complementary; “C” buildings do not relate to the heritage character, though anything that replaces them must be compatible. Your property’s classification, and the specific plan for your district, shapes what staff will approve.

What this means for aluminum on a heritage-district house

For a designated or “A”-type village house with original wood clapboard, the honest answer is that new aluminum siding is unlikely to be the approved route, and you should expect the City to favour repair of the original wood. Where aluminum can still play a role is on later, non-contributing buildings, on rear additions, on eavestrough repairs, and on details that staff accept. We will tell you that plainly at the estimate rather than sell you a job the district plan does not support.

Markham in numbers: the facts that shape exterior work

Markham is a big, mostly detached-house city with snowy winters and a short, compressed exterior season. These are the checkable figures we lean on when planning work here; each is listed in the sources at the bottom of the page.

• 110,870 dwellings, 62,290 single-detached. York Region’s 2021 Census release report puts single-detached houses at 56% of Markham’s dwelling units. Detached houses carry the most soffit, fascia and trim per household.
• 146.4 cm of snow a year. The 1991–2020 Environment and Climate Change Canada normals for the Buttonville station, as compiled on Markham’s Wikipedia climate table, show 146.4 cm of annual snowfall and 862.4 mm of total precipitation.
• A January daily mean of −6.0 °C. Freeze-thaw swings around that average are what push meltwater into gaps at fascia joints and window sills.
• Markham Village district created in 1991, with 709 properties. The City’s plan-update FAQ describes it as one of Markham’s oldest heritage districts and its largest.
• Four heritage conservation districts. Thornhill, Markham Village, Buttonville and Unionville.
• Rapid post-1970s growth. Markham became a town in 1971, and its population grew from roughly 56,000 in 1976 to more than five times that. It became a city on July 1, 2012.

Put together, those facts explain the local pattern. A small number of 19th-century village streets carry strict heritage rules, while the bulk of Markham’s homes date from the 1970s onward and are now reaching the age when original wood trim, first-generation aluminum and builder-grade eavestrough are due.

Eight kinds of Markham homes and what their exteriors usually need

Markham is not one housing stock. The right material, profile and scope change sharply between a Main Street Unionville house and a 2010s townhouse in Cornell. Here is how we think about the city’s main home types.

1. Village houses inside the heritage districts

These are the 19th- and early 20th-century houses along Main Street Unionville and Main Street Markham and the side streets around them. Typical features are painted wood clapboard, wide cornerboards, decorative bargeboards, and wooden porches. The work here is mostly sympathetic eavestrough repair and, where the City approves it, carefully matched trim details. Expect heritage review on most exterior changes.

2. Infill and later houses within a district

Every district contains newer houses built between the older ones. These may be classed as complementary or non-contributing, but the City’s permit rule still applies to them because they sit inside the boundary. Aluminum soffit, fascia and capping are often more realistic on these homes, subject to a minor heritage permit.

3. Thornhill on the Markham side

Thornhill straddles the Markham–Vaughan boundary along Yonge Street, and it has its own heritage district around the old village. Beyond that core, the Markham side has mature mid-century and 1970s–80s subdivisions under heavy tree canopy. Leaf load is the defining issue: eavestroughs clog early in autumn and overflow onto fascia boards. Neighbours across Yonge Street face the same conditions, which we cover on our Vaughan service area page.

4. 1970s backsplits and side-splits

Markham’s first wave of suburban growth produced split-levels with brick lower storeys and upper storeys finished in wood, aluminum or early vinyl. Many still have original painted wood fascia and window brickmould. These are prime candidates for custom-bent aluminum capping over the remaining wood trim, often paired with a soffit refresh.

5. 1980s two-storeys

The two-storey brick house with an aluminum-clad upper gable and a double garage is a Markham staple. Common problems include chalky, faded factory aluminum, dented lower panels near driveways, and rotted wood around the garage opening. Garage door frame capping is one of the most requested jobs on this era of house.

6. 1990s executive homes

Larger lots, taller elevations, more roof planes and a lot more linear footage of soffit and fascia. Builder-grade eavestrough from this era is often 5-inch with too few downspouts for the roof area it drains. Height also raises access costs.

7. 2000s and 2010s subdivisions

Communities such as Cornell, Berczy Village and Wismer were built with factory aluminum soffit and fascia and vinyl or brick facades. These homes rarely need a full re-side. What they do need is targeted repair: storm-loosened fascia, sagging trough sections, failed downspout connections, and occasional replacement of a damaged soffit run after an animal gets in.

8. Townhouses and semis

Row and semi-detached homes share eavestroughs and trim lines with neighbours. A good job matches the adjoining unit’s colour and profile so the block still reads as one building. Coordinate with your neighbour or condo board before changing colours.

How to match heritage-appropriate profiles and colours

Whether or not you live inside a district, a Markham exterior looks best when new aluminum respects the house’s original proportions. This is the method we use, and it doubles as preparation if you need a heritage permit.

Start with the original profile

Older Ontario houses usually had narrow horizontal wood clapboard, often around a 4-inch exposure, with flat cornerboards and plain or moulded window casings. If a non-heritage home nearby has that look and you want aluminum siding to echo it, choose a narrow horizontal profile rather than a wide double-panel style, and keep the cornerboards visible as distinct trim rather than letting the siding run into a thin corner post.

Keep trim depth and shadow lines

When we cap wood trim, the aim is to follow the original shape, not flatten it. A brickmould that steps out from the wall should still step out after capping. Sills keep their slope so water drains away. Flattening these details is the fastest way to make a house look covered up rather than restored.

Choose colours in families

The Unionville plan asks that exterior finish and trim colours be sympathetic to the original where possible and rules out fluorescent or luminous colours. A practical approach for any Markham home is to pick one body colour and one trim colour, keep both within muted, period-appropriate families such as cream, off-white, deep green, warm grey or dark brown, and make the soffit, fascia and eavestrough read as one trim line. Prefinished aluminum coil from Canadian suppliers such as Kaycan and Gentek comes in broad colour ranges, which makes matching easier.

Bring samples, not screen colours

Colours shift dramatically between a phone screen and a north-facing wall in February. Hold physical coil samples against your brick or existing siding in daylight, and if you are applying for a heritage permit, include the colour names in your submission.

Nine upgrades Markham homeowners ask for most

Outside the heritage districts, most Markham projects are about replacing tired original materials with low-maintenance aluminum. These are the jobs we quote most often, roughly in order of how frequently they come up.

1. Window capping on 1970s–80s homes. Original wood brickmould and sills on homes from this era have often been painted many times and are beginning to soften. Replacing old window capping or capping bare wood ends the repainting cycle.
2. Garage door frame capping. The bottom of the wood jamb sits in splash zone and salt slush every winter. We measure the frame, cut and bend aluminum to fit, and attach it with adhesive and/or screws.
3. Soffit replacement with ventilated panels. Older solid wood or early aluminum soffit is swapped for vented aluminum to support attic airflow. See our soffit and fascia service for how we handle it.
4. Fascia wrapping. Painted wood fascia behind the eavestrough is wrapped in aluminum after any soft sections are replaced.
5. Seamless eavestrough replacement. Sectional troughs with leaking joints are replaced with seamless runs formed on site. Our eavestrough installation and repair page explains sizing.
6. Upgrading downspouts. More or larger downspouts, extended away from foundations, especially on 1990s homes with large roof areas.
7. Front entry door frame repair. Rot at the base of the door jamb is cut out and rebuilt before capping. Our window and door frame repair page covers the process.
8. Full aluminum re-siding of upper storeys. On brick-and-siding two-storeys, aluminum siding replacement means replacing faded first-generation aluminum or brittle vinyl on the upper level and gables.
9. Dormer cladding. Dormers on 1.5-storey and older homes get wrapped and capped so their cheeks and trim stop needing paint.

What does this cost in Markham? A ballpark breakdown

These are typical GTA ballpark ranges (2026). Your written quote after an on-site measure is what counts. Markham pricing follows the same ranges as the rest of the GTA; the real differences come from house height, access, trim complexity and how much rot we find.

Factors that move price on any job: height and number of storeys, access, tear-off, rot found, colour and gauge, custom bends, and season. For a heritage-district property, also leave time in your schedule for the City’s review.

Comparing your options: repair, aluminum or vinyl

The right material depends heavily on where in Markham your house sits. This table compares the three most common approaches for exterior walls and trim.

For most Markham homes outside the districts, the practical answer is a mix: keep the brick, cap the wood trim in aluminum, replace soffit and fascia, and re-side only the elevations that need it.

Step by step: planning an exterior project on a heritage-district property

If your house is inside the Unionville, Markham Village, Thornhill or Buttonville district, follow this order so you do not pay for materials you cannot install.

1. Confirm your boundary and classification. Check the City of Markham’s heritage district maps and ask Heritage Section staff whether your property is inside a district and how it is classified.
2. Define the scope in writing. List each element you want to touch: eavestrough repair, fascia, soffit, window trim, siding on a rear addition. Separate repairs from replacements, because the City treats them differently.
3. Get an on-site estimate. Have a contractor measure, photograph and describe the materials and profiles they propose. Ask for the colour names and profile dimensions in writing.
4. Ask the City which permit applies. Share the scope and photos with Heritage Section staff. Minor permits are typically handled by staff when the work complies with approved policies and guidelines.
5. Adjust the design. If staff ask for wood repair instead of capping, or a different profile or colour, revise the quote before applying.
6. Submit and wait for approval. Do not schedule installation until you hold the approval.
7. Install and document. Keep before-and-after photos with your permit for your records and any future sale.

What we check on a Markham estimate visit

Our inspection framework is the same structured walk-around on every house, adjusted for the era and location of the home. Here is what we look at and why it matters in Markham specifically.

Before-you-book checklist for Markham homeowners

• Confirmed whether my address is inside a Markham heritage conservation district.
• If it is, asked Heritage Section staff whether my project needs a minor or major heritage permit.
• Listed which items are repairs and which are replacements.
• Checked whether a porch, deck or dormer change also needs a building permit from the City’s building department.
• Talked to my neighbour or condo board if I share a wall, roofline or eavestrough.
• Chosen body and trim colours from physical samples in daylight.
• Received an itemized written quote with profiles, colours and gauges listed.
• Confirmed the contractor’s liability insurance and WSIB coverage.
• Understood how rot found during the job will be priced.
• Received the warranty terms in writing.

Template: heritage permit conversation worksheet

Thornhill, Unionville and the suburbs: how the work changes across the city

Markham’s geography changes the work as much as its history does. In the village cores, the priority is restraint: small repairs, matched details and approval first. In treed Thornhill-side streets, eavestrough capacity and leaf management matter more than anything else. In the newer east and north subdivisions, the work is mainly repair on factory-installed aluminum.

If you are near the city’s edges, the same thinking extends into neighbouring communities. Homes in north Scarborough share much of the 1970s–80s housing stock, which we describe on our Scarborough service area page, while homes north of Highway 7 near Bayview are closer in character to Richmond Hill’s large two-storeys. You can also see every community we visit on the service areas hub.

Ready to talk through a Markham project? Call (647) 560-9038 or use our free estimate form.