Siding Companies London: How New Siding Pairs with Fresh Windows

Posted on 2026-03-17 00:11:16

Most homeowners start with a drafty room or peeling cladding and end up facing the bigger picture. If the siding is near its end and the windows are fogging up or hard to latch, doing both together is more than a convenience. It is a chance to rebuild the envelope correctly and reap long term gains in comfort, durability, and curb appeal. In London, Ontario, where winter lows routinely dip below freezing and lake effect moisture sneaks into laps and joints, aligning window replacement with new siding is one of the smartest moves you can make.

I have walked through dozens of projects across Old East Village, Westmount, and newer subdivisions south of Exeter Road. The pattern repeats. Houses that tackle windows and cladding at the same time look sharper, test tighter for air leakage, and suffer fewer callbacks. The difference is not luck. It comes from proper sequencing and careful integration of the weather barrier, flashings, insulation, and trim.

Why pairing windows and siding matters in London, Ontario

London winters are long enough to expose weaknesses. Wind driven rain in October becomes wind driven snow in January, and spring thaws find every tiny pathway water can use. On a typical detached home built between 1970 and 2000, you will find original vinyl or aluminum siding over building paper, with wood framing and modest wall insulation. Windows in those years often have aluminum or early vinyl frames with double glazing, sometimes with failing seals. Replacing only the windows leaves the old weather barrier and flashing details in place. Replacing only the siding but keeping aged windows means trying to integrate new flashing into old vinyl nailing fins or beat up wood jambs. Either route invites leaks at the head and sill or cold spots that frosting loves.

When you handle window replacement and new siding as a coordinated scope, you get the layers in the right order. The window integrates with a continuous weather resistive barrier, flashing tape bridges the rough opening to the WRB, and the cladding sheds bulk water while a vented air space lets the wall dry. That is the difference between a pretty exterior and an exterior that lasts.

The right sequence, simplified

A strong project plan reduces site improvisation. Crews in window installation London Ontario circles share a version of the same rhythm because it works, and it meets manufacturer warranties.

Remove existing cladding and trim down to the sheathing, assess and repair substrate. Establish or upgrade the continuous weather resistive barrier, including taped sheathing seams. Set new windows and patio doors with pan flashing, side and head flashings, and integrate nailing fins to the WRB. Add exterior insulation if planned, then install strapping to create a vented rainscreen cavity. Hang the new siding, finish with trims, sealants at the right joints, and cap or clad as specified.

Each of those five steps holds dozens of decisions, but that is the backbone. If you keep that order, you avoid the most common water entry points and air leaks.

What a good opening looks like before the window goes in

You can tell a lot about a siding company and a window crew by how they prep a rough opening. On tear off day, we expose the sheathing, then check for soft spots around sills. London’s freeze thaw can rot the lower corners behind old aluminum sliders, so assume you will replace some sheathing or framing blocks. The opening gets cleaned thoroughly. If the design calls for an exterior sill slope, use beveled wood or composite shims so the inner sill stays level while the outer sheds water. We preform a sill pan or build one with self adhered flashing that wraps the sill and runs at least several inches up each jamb. Corners get tight folds or preformed corners, not slits and patches. Only then does a bead of sealant hit the back of the nailing fin, never as the only line of defense but as part of a layered system.

For window replacement London Ontario homeowners often ask about doing windows before siding to “lock the house up.” I understand the concern, especially if a storm is coming. The answer is to stage openings. Work on one or two elevations at a time, and integrate the WRB and flashing as you set each window. Leaving a fully finished WRB section overnight is fine. Slipping a new window into old siding and planning to “figure out the flashings later” is how small leaks become big repairs two winters down the road.

Full frame or retrofit: what plays well with new siding

In a pure window replacement London project without siding, insert windows can make sense. You keep the existing frames and interior trim, and you replace the sashes and glass. With siding coming off, the case for full frame grows stronger. A full frame window lets you:

Correct the opening size, plumb and square. Replace water damaged framing at the sill. Insulate the cavity perimeter fully instead of packing foam against a tired old jamb. Install modern units with nailing fins and factory head flashings that tie cleanly into the WRB.

I nearly always recommend full frame for window and door replacement London when siding is part of the scope. The exceptions are heritage facades where exterior trim must remain, or very recent windows that are truly sound. In those cases, a careful integration of new flashing membranes around existing units can work, but it adds time and risk.

The rainscreen earns its keep

Ontario does not mandate a rainscreen cavity on every wall, but a 10 to 13 mm ventilation space behind cladding is cheap insurance in a climate with regular wetting. The physics is simple. If you keep a small air gap between the siding and the WRB, you limit capillary wicking, you let incidental water drain, and wind pressure cycles promote drying. Furring strips or drainage mats create the space. Combine that with a high quality WRB, properly lapped and taped at seams, and you have a wall that forgives small mistakes instead of magnifying them.

I have opened walls that had perfect siding and decent windows, yet the sheathing was blackened at sills. Every time the cause was the same: no pan at the sill and no air gap behind the cladding. When siding companies London crews add that gap and a true sill pan, callbacks drop dramatically.

Exterior insulation without the headaches

When siding comes off, you have access to the cheapest way to add effective wall R value: continuous exterior insulation. Even 25 to 38 mm of rigid foam or mineral wool cuts thermal bridging at studs and makes the interior surface of the wall warmer, which prevents condensation inside. The trick is to plan window placement with that added thickness in mind. If you push the window out to align with the rain plane, your trim details will look modern and clean, and your sill will actually shed water better. If you keep the window in the original plane and add exterior insulation, you need jamb extensions. Neither approach is wrong, but someone has to own the detail before framing day.

The cost in London Ontario ranges widely. Material and labour for 25 mm rigid foam with new strapping can add a few dollars per square foot. For many homes, the energy savings and comfort boost pay it back over a handful of winters, especially if you are pairing this with a high performance window package. If your budget is tight, at least target the windward and north facing elevations. Those are the walls that most often show cold striping and paint cracking indoors.

Choosing the right window for performance and fit

When homeowners search for London Ontario windows, they usually get inundated with glass packages and marketing terms. In the field, I focus on a handful of things that matter.

Frame and sash quality. High quality vinyl, fiberglass, or clad wood frames resist warping under seasonal expansion. In our winters, flimsy frames bow and leak air. Fiberglass stands out for stability, but premium vinyl has proven itself as well. Glass specifics. Double pane with low emissivity coatings and argon is the floor. Triple pane can be worthwhile for bedrooms or street facing rooms where traffic noise adds to the benefit. Manufacturers publish U factors and solar heat gain values. I look for low U factors for winter comfort and consider moderate solar gain on south elevations. Hardware and weatherstripping. Check the compression seals at the corners and the feel of the locks. Leaky weatherstripping destroys the point of a good glass unit.

For window installation London Ontario crews, the local weather teaches respect for head flashings. Whether the unit includes an integral drip cap or you add a separate metal head flashing, it should kick water out past the face of the siding, with end dams that return to the wall. Never rely solely on caulk at the top trim.

Siding choices that pair well with fresh windows

The window line and the cladding speak to each other. Deeply profiled vinyl with skinny window trims looks lopsided. Fiber cement with thick casing and modern black frames can look sharp on a brick and siding mix that is common in London’s suburbs.

Vinyl siding. Economical, light, and common. Modern vinyl holds colour better than the 1990s products, and insulated vinyl can modestly reduce noise. Pair with crisp PVC or aluminum trims around windows. Fiber cement. Heavier and more fire resistant. It takes paint beautifully and pairs well with contemporary window packages. Needs corrosion resistant fasteners and careful dust control on site. Engineered wood. Warm look with factory finishes that last. Slightly softer than fiber cement, but installation is faster and the product lines offer matching trims. Steel siding. Durable and excellent in high exposure locations. With black or charcoal windows, steel profiles can deliver a clean modern palette. It can sound “tingy” during rain without an air gap, another reason to include a rainscreen.

The material you pick also affects the trim package. Wider flat trims feel right with fiber cement and steel. With vinyl, integrated J channels are common, but oversize trims can elevate the look if the budget allows.

Details that make windows and siding read as one design

Curb appeal is not just colour. It is the way lines and shadows add up. A few practical rules help:

Align head heights on a façade where possible. Staggered window heads behind a continuous soffit look accidental. Choose trim depths to overcome added insulation. If you added 25 mm of foam, step up to thicker casings so the windows do not look recessed unintentionally. Pick a finish strategy that respects exposure. South and west faces fade faster. Fibre cement and high end vinyl maintain colour longer. Dark colours on vinyl should be from lines rated for solar heat to prevent warping.

I often mock up one bay with the agreed trim, J channel or casing, and siding before committing the whole job. Ten minutes with a few offcuts can avert a thousand dollars of second guessing.

Energy, comfort, and the quiet that surprises people

Air sealing and thermal continuity do more for comfort than most brochures admit. With a new window and doors London Ontario package, plus fresh siding over a continuous WRB and perhaps a layer of exterior insulation, the stack effect in winter weakens. That means fewer drafts at baseboards and along stairwells. The interior face of the wall stays warmer, and that removes the radiant chill you sometimes feel when you https://andersonexsp497.wpsuo.com/step-by-step-window-installation-london-ontario-what-to-expect sit near an old window in February.

Noise is the bonus. Triple pane glass and a rainscreen cavity take the edge off street sounds. Homeowners on Highbury or Wonderland often comment on that improvement first, before noticing their gas bill dropped.

Budget planning that avoids surprises

Ranges help, but site conditions swing the numbers. In London, Ontario, installing mid range vinyl windows via full frame replacement often lands in the mid hundreds to just over a thousand dollars per opening for the unit alone, plus installation that can run similarly depending on size and trim complexity. Triple pane or fiberglass frames push higher. For siding, vinyl installed with new WRB and trims may start in the mid single digits per square foot and climb with material and detail choices. Fiber cement or steel adds a few dollars more per square foot, largely from labour and fasteners.

Two budget flags to plan for:

Sheet goods and framing repairs around sills. Once the old layers come off, some rot is common. Set aside a contingency line so the crew can fix rather than patch. Window size changes. Squaring openings sometimes means adjusting framing. If you are already redoing trim and siding, it is usually worth it to get ideal proportions.

When you combine scopes, you also combine savings. One mobilization, one scaffold or lift rental, one permit process. Coordinating window replacement London Ontario with siding reduces duplicated labour around trimming, capping, and caulking.

Doors deserve a seat at the table

A tight envelope is only as strong as its largest holes. If your back slider grinds in its track or you feel a winter breeze at the front entry, bring doors into the same scope. Patio door installation ties into the same flashing routines as windows, but the stakes are higher because the opening is bigger. A proper sill pan on a patio door is non negotiable, and end dams that kick water away from the threshold save flooring inside.

For front entries, steel doors London Ontario offers combine security with energy performance. Modern insulated steel slabs with composite frames handle temperature swings and drafts better than many older wood units. Steel door installation London Ontario contractors who do both windows and siding understand how to integrate the sill, the frame flashing, and the cladding so the threshold stays dry. If you are already setting up exterior insulation and a rainscreen, detailing the door trim to project past the cladding keeps water moving out where it belongs.

If you only have room in the budget for one door, prioritize the worst air or water leak. Often that is a tired patio door on the north or west face that takes the brunt of weather.

Permits, inspections, and warranty fine print

In most cases, replacing windows and siding on a single family home is straightforward, but any change to structural openings or egress size should go through the proper permitting channels. If you enlarge a basement window for egress or convert a window to a patio door, check setback and guard requirements. When you hire siding companies London teams, ask who owns the permit process and how manufacturer warranties are protected. Many brands require specific fasteners, clearances above roofs and decks, and ventilation gaps behind the cladding. Window manufacturers are just as strict about flashing details and foam use around frames.

A word on foam. Low expansion foam is appropriate for most window perimeters. Overfilling can bow frames and ruin operation. Trim carpenters sometimes try to silence rattles with regular can foam. That works until the sash binds in July. Make sure the crew uses the right product and gun.

A short case from the field

A brick and vinyl split level in Byron had 30 year old sliders and chalky clapboard. The owners wanted a quieter living room facing Boler Road and lower winter bills. We stripped the vinyl, left the brick, and installed a robust WRB over the sheathing with taped seams. New fiberglass windows went in full frame, with pan flashings and metal head flashings that kicked out past the future siding face. We added 25 mm rigid insulation over the sheathing, then strapping at 400 mm centres to form a rainscreen. Fiber cement lap siding with PVC trims framed the black window units. The back patio door was replaced during the same mobilization with a welded sill pan, sloped to daylight over the new cladding.

On blower door test, the house tightened by more than 20 percent compared to a pre job reading. The homeowners noticed the road noise drop immediately. We had two small sheathing patches where old sills had leaked, but the contingency covered it. Three winters later, the paint on interior walls near exterior corners still looks fresh, with no condensation lines, and the patio threshold has stayed dry after every spring deluge.

Common pitfalls and how to sidestep them

The most frequent mistake is trusting caulk to do the job of layered flashing. Sealant is a maintenance product, not a waterproofing system. The second is skipping the sill pan because it feels fussy. Without a pan, water that inevitably finds the rough opening sits against wood until it wins. Third, watch the head trim. I have seen handsome windows capped with aluminum and tucked under siding, but the flashing stopped short of the face. It looked clean on day one and leaked by year two. Metal head flashings should extend out and to the sides, with end dams that prevent water from curling behind the trim.

On the insulation front, mismatched window placement and exterior foam can create deep wells around windows that collect water and debris. If you are pushing the window out to plane with the insulation and cladding, commit to returns and trims that match. If not, plan clean jamb extensions and sloped sills so water runs out.

Working with local contractors without losing sleep

A combined scope demands coordination. Some companies in the window and doors London Ontario market also run full siding crews. Others partner. Either model can work if someone serves as the single point of responsibility. Ask to see one or two recent projects where they did both. The best test is how they talk about sequencing and the WRB. If the salesperson cannot explain how they integrate the nailing fin to the barrier and how they vent the cladding, keep looking.

A simple homeowner checklist helps keep the project on the rails:

Confirm who owns design details for head flashings, sill pans, and trim depths. Ask how they will protect landscaping and manage waste during tear off. Get material submittals for WRB, flashing tapes, fasteners, and cladding. Walk the first installed window and siding bay before they proceed with the rest. Clarify warranty responsibilities for both window units and installed cladding.

If those five items are answered clearly, the rest usually follows.

Timing, weather, and living through the work

Window replacement London Ontario in March can be messy. In July it can be dusty. The crew’s plan to maintain a dry, secure house during the swap matters. Most teams work elevation by elevation, removing cladding in a controlled area, installing WRB and windows, then moving on. Good tarps, temporary seals, and a tidy site reduce stress. If security worries you, ask them to finish a façade fully before swinging around the corner. In practical terms, a typical three bedroom house with 12 to 16 windows and full siding can run one to three weeks depending on manpower, weather, and complexity of details like exterior insulation or custom trims.

Where doors fit in the project calendar

Door installation London Ontario is best scheduled right after the window sets on that elevation, while the crew is still open to make flashing adjustments and before the siding locks in trim positions. Patio door installation should not be rushed late on a Friday. Give it half a day, minimum, so the threshold, the sill pan, and the interior transitions can be set cleanly. If you are upgrading to a steel entry, plan the interior flooring transition too. Raising or lowering thresholds to clear new siding and exterior insulation can throw off tile or hardwood heights if forgotten.

Bringing it all together

When you combine fresh siding with window replacement, you are not just buying new skin and new glass. You are rebuilding the control layers that keep your home dry, comfortable, and quiet. The pieces work together. The WRB is the unsung hero, the rainscreen gives the wall forgiveness, the flashings steer water, and the cladding takes the weather. The window package locks out drafts and keeps the interior surface warm, which changes how your home feels in January.

Look for siding companies London homeowners trust that can speak fluently about these layers, not just colours and styles. Treat the details as essential rather than extras. If you fold in the entry and patio doors while you are at it, you finish the envelope in one clean pass. London Ontario windows and doors vendors who collaborate closely with installers can help you pick the right glass, frames, and cladding to match your goals and your budget. Done right, the house is tighter, quieter, and, years from now, far less likely to surprise you with a soft sill or stained drywall.

The last point is a small one that ends up big. After the crew leaves, keep the exterior clean and the sealant joints inspected. Once a year, wash the siding gently and check the head flashings for leaves or debris. Open and close every operable sash and door to keep weatherstripping seated. These habits cost almost nothing, and they preserve the investment you made when you chose to coordinate window installation London Ontario with a full siding upgrade.

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Name: McCallum Aluminum Ltd

Address: 3392 Wonderland Rd S, London, ON N6L 1A8, Canada

Phone: (519) 433-4223

Website: https://mccallumaluminum.on.ca/

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McCallum Aluminum Ltd is a trusted window and door installation company serving London ON.

For door replacement in the surrounding area, contact McCallum Aluminum Ltd at (519) 433-4223 or visit https://mccallumaluminum.on.ca/.

McCallum Aluminum Ltd provides expert exterior renovation help for exterior doors, helping homeowners improve comfort across nearby communities.

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Looking for a affordable installer near you? Call (519) 433-4223 and learn more at https://mccallumaluminum.on.ca/.

Landmarks Near London, Ontario

1) Victoria Park — Visiting downtown? Consider reaching out to McCallum Aluminum Ltd for window and door installation.

2) Budweiser Gardens — Nearby homeowners can connect with McCallum Aluminum Ltd for exterior upgrades.

3) Covent Garden Market — In the core? Ask about window and door replacement options.

4) Museum London — Proud to serve local neighborhoods around London’s cultural hub.

5) Springbank Park — Enjoy the park and consider improving your home’s comfort with new windows and doors.

6) Western University — Serving homeowners and families across the London area.

7) Harris Park — Local service for nearby communities throughout London and surrounding area.

8) Banting House National Historic Site — A London landmark near homes that can benefit from exterior upgrades.

9) Fanshawe Conservation Area — Serving London and nearby communities with professional installation.

10) Masonville Place — In North London? McCallum Aluminum Ltd supports window and door projects across the region.