Siding Contractors

Portland Siding Contractors: Expert Installation, Repair, and Replacement

Siding does more work than most homeowners realize. It is the primary weather barrier between Portland's relentless moisture and the framing, sheathing, and insulation that keep your home standing. When siding fails, water gets behind it. You do not always see the damage until sheathing is rotted, insulation is saturated, and mold has colonized the wall cavity. In a climate that delivers 40-plus inches of rain per year, months of sustained drizzle, and enough shade to keep moss thriving on north-facing walls year-round, siding selection and installation quality are not cosmetic decisions. They are structural ones.

Boss PDX is a licensed Oregon general contractor (CCB #232383) specializing in siding installation, replacement, and repair across the Portland metro area. We work on everything from 1920s Craftsman bungalows in Laurelhurst to mid-century ranches in Milwaukie to new construction in Hillsboro. We handle the full scope: old siding removal, sheathing inspection and repair, housewrap and moisture barrier installation, new siding, flashing, trim, and caulking. When a re-side project uncovers rot, inadequate insulation, or outdated wiring, we have the crews and licenses to address it without bringing in a separate contractor.

Siding Materials We Install

Every siding material has tradeoffs. Cost, lifespan, maintenance burden, moisture performance, and aesthetics all factor in. Portland's climate narrows the field. Materials that perform well in dry climates can fail here. We install and recommend the following options based on decades of experience with how they hold up in the Pacific Northwest.

Fiber Cement Siding (James Hardie)

Fiber cement is the dominant siding choice in Portland for good reason. James Hardie HardiePlank and HardiePanel products are engineered from Portland cement, sand, and cellulose fibers, producing a material that will not rot, is not appetizing to woodpeckers or carpenter ants, and carries a 30-year limited warranty when installed by a certified contractor. Hardie's ColorPlus finish is factory-applied and baked on, offering better color retention than field-painted alternatives and a 15-year finish warranty.

Fiber cement handles Portland's moisture cycle well. It does not absorb water the way wood does, which means no swelling, warping, or splitting through wet-dry seasons. It is also non-combustible, which matters for homes near wildland-urban interface zones in areas like Forest Park or the West Hills.

The tradeoff is weight and installation difficulty. Fiber cement is heavy, typically 2.5 pounds per square foot for lap siding. It requires scoring and snapping or cutting with specialized shear tools (not a circular saw spewing silica dust). Improper installation, particularly failing to leave proper clearance above rooflines and at horizontal surfaces, is the most common source of fiber cement siding failure. We follow Hardie's installation specifications to the letter, including blind-nailing with corrosion-resistant fasteners, maintaining the required 1/4-inch gap at butt joints, and using Hardie-approved flashing at all penetrations.

Installed cost: $9 to $14 per square foot, including removal of old siding and housewrap.

Vinyl Siding

Vinyl remains the most affordable siding option and has improved significantly from the thin, wavy panels of the 1980s. Modern insulated vinyl siding panels include a rigid foam backing that improves both impact resistance and R-value. Good vinyl siding will not rot, does not need painting, and will not be eaten by insects.

The limitations are real, though. Vinyl is a plastic product that expands and contracts with temperature swings. In Portland, where a January day can swing from 28 degrees at dawn to 50 by afternoon, that thermal movement is constant. Vinyl must be hung loosely on nails so it can slide, and every joint must leave an expansion gap. Improperly nailed vinyl buckles. Vinyl also melts near heat sources, can crack in extreme cold, and fades over time with UV exposure. Replacement panels from a different production run may not match.

We install vinyl siding when budget is the primary constraint, particularly on investment properties, ADUs, and homes where the owner plans to sell within a few years. For a primary residence where you want 30-plus years of performance, we typically steer clients toward fiber cement or engineered wood.

Installed cost: $5 to $8 per square foot.

Cedar and Wood Siding

Western red cedar has been the traditional siding material in the Pacific Northwest for over a century. Cedar contains natural oils that resist rot and insect damage, and when properly maintained, a cedar-sided home can look exceptional for 50 years or more. Many of Portland's most iconic homes, the Craftsman bungalows in Irvington, the Arts and Crafts houses in Alameda, the Victorians in Nob Hill, wear original or restored cedar siding.

The catch is maintenance. Cedar must be stained or painted every 4 to 7 years in Portland's climate. Skipping a cycle invites moisture penetration, and once cedar starts to rot, the damage accelerates. South-facing and west-facing walls take the worst UV and rain exposure and tend to need attention sooner. Moss and algae growth on shaded walls is constant and must be cleaned annually to prevent surface degradation.

We install clear vertical grain (CVG) cedar lap siding, tongue-and-groove cedar, and cedar shingle siding. For historic homes in Portland's designated historic districts, cedar is often the only siding material that will satisfy the Historic Landmarks Commission review, and we have experience navigating that process. If your home is in Ladd's Addition, Irvington, Piedmont, or another historic overlay zone, talk to us before choosing a siding material.

Installed cost: $10 to $18 per square foot for lap siding; $12 to $22 per square foot for cedar shingles.

Engineered Wood Siding (LP SmartSide)

LP SmartSide is an engineered wood product made from treated wood strands bonded with resin and wax. It offers the look and workability of real wood at a lower cost than cedar and with significantly better moisture and decay resistance. The SmartGuard manufacturing process treats the wood strands with zinc borate, providing built-in protection against termites and fungal decay. LP backs it with a 5/50-year limited warranty (5 years on finish, 50 years on substrate).

Engineered wood siding cuts and nails like real wood, which means faster installation and easier integration with custom trim profiles. It is lighter than fiber cement, reducing the structural demand on older wall framing. For Portland homes built before 1960, where wall studs may be true 2x4 with minimal sheathing, that weight advantage matters.

The main consideration with LP SmartSide is that it must be painted. Factory-primed panels ship ready for a topcoat, and the substrate is less forgiving than fiber cement if paint maintenance lapses. In Portland, that means committing to a repaint cycle every 7 to 10 years. We often pair LP SmartSide installations with a referral to our painting team for the initial topcoat and future maintenance scheduling.

Installed cost: $7 to $11 per square foot.

Cedar Shingle Siding

Cedar shingles and shakes create a textured, dimensional look that suits many Portland architectural styles, from Craftsman to Cape Cod to contemporary designs that use shingles as an accent material. Shingles are typically applied over furring strips or a rainscreen system, which creates a ventilated air gap behind the siding. That air gap is arguably more important in Portland than anywhere else: it allows moisture that penetrates the shingle layer to drain and dry rather than sitting against the sheathing.

We install both sawn shingles (smooth, uniform thickness) and hand-split shakes (rougher, more rustic). Shingle siding is labor-intensive. Each piece is individually placed, and corners, valleys, and window surrounds require careful cutting and weaving. Budget accordingly: a full shingle re-side typically costs 30 to 50 percent more than lap siding in the same material.

Installed cost: $12 to $22 per square foot.

Board and Batten Siding

Board and batten, wide vertical boards with narrow strips (battens) covering the joints, is seeing a resurgence in Portland. It works well on modern farmhouse designs, ADUs, and as an accent on gable ends or entryways. We install board and batten in fiber cement (Hardie), LP SmartSide, and natural cedar. The vertical orientation sheds water efficiently, and the raised battens create shadow lines that add depth to the facade.

Proper board-and-batten installation requires a flat substrate. On older Portland homes with wavy sheathing or no sheathing at all (common in homes built before 1940), we may need to install new OSB or plywood sheathing before the siding goes on. That adds cost but is non-negotiable for a straight finished wall.

Installed cost: $9 to $16 per square foot depending on material.

The Siding Installation Process

A quality siding job is 60 percent preparation and 40 percent hanging panels. Cutting corners on prep is how siding fails within a decade. Here is how we approach a full re-side project.

Inspection and Scope

We start with an on-site inspection of the existing siding, probing for soft spots, checking moisture levels with a pin meter, and evaluating the condition of trim, flashing, window and door surrounds, and any visible housewrap or building paper. We also check the condition of the roof edge, gutters, and downspouts, since roofing issues directly affect siding longevity. This inspection drives the scope of work and accurate pricing.

Permits

In Portland, residing a home with the same material type (like-for-like replacement) does not typically require a permit from the Bureau of Development Services (BDS). However, if you are changing siding material, adding or modifying wall insulation, altering window or door openings, or working on a home in a historic district or design overlay zone, a permit is required. We handle the BDS permit application process, including any required plan review, and schedule inspections as needed. For homes in unincorporated Multnomah County, Clackamas County, or Washington County, permitting requirements vary and we coordinate with the applicable jurisdiction.

Old Siding Removal

Removing old siding is the phase where you find out what the house has been hiding. Common discoveries on Portland homes include:

• Rotted sheathing around windows, at the base of walls, and behind downspouts where water has been splashing for years
• No sheathing at all on pre-1940 homes, just building paper tacked directly over studs
• Asbestos-containing materials in homes built between the 1920s and 1970s, including cement-asbestos shingles and some underlayments (we follow Oregon DEQ abatement requirements when asbestos is present)
• Inadequate or missing insulation in wall cavities
• Outdated wiring including knob-and-tube, run through wall cavities without protection
• Previous siding layered over old siding instead of being properly removed

We budget contingency into every re-side estimate because these discoveries are the rule, not the exception, on Portland homes over 40 years old. Addressing them during the re-side is far more cost-effective than dealing with them later.

Sheathing Repair and Replacement

Damaged sheathing must be cut out and replaced before any new siding goes on. We use exterior-grade OSB or CDX plywood depending on the application. On homes with no sheathing (common on older Portland construction), we install new structural sheathing across the entire wall surface to provide a solid nailing base and improve the building's racking resistance.

Moisture Barriers and Housewrap

The moisture management layer is the most critical component of a siding system, and it is entirely hidden once the siding is installed. We use Tyvek HomeWrap or equivalent water-resistive barrier (WRB) on every re-side project. The housewrap is lapped shingle-style (upper courses over lower), with all seams taped and all penetrations sealed with compatible flashing tape.

Window and door openings get particular attention. We install self-adhering flashing membrane at sill pans, jambs, and head flashing in a specific sequence designed to direct any water that penetrates back to the exterior. This detail is prescribed by Oregon Residential Specialty Code and is the single most common point of failure in siding installations. Done wrong, water enters the wall at every window. Done right, the window becomes a watertight unit even if the siding above it is damaged.

For fiber cement and cedar installations, we increasingly recommend a rainscreen system: a layer of vertical furring strips over the housewrap that creates a 3/8-inch to 3/4-inch ventilated air gap behind the siding. This gap allows any incidental moisture to drain to the bottom of the wall and dry via air circulation. In Portland's climate, where walls may not fully dry for months at a time, a rainscreen is the difference between siding that lasts 30 years and siding that lasts 50. The added material and labor cost is modest, typically $1 to $2 per square foot.

Insulation Upgrades During Re-Siding

A re-side is the ideal time to upgrade wall insulation. With the siding off and potentially the sheathing exposed, adding insulation to wall cavities is straightforward and relatively inexpensive compared to doing it as a standalone project. Options include:

• Dense-pack cellulose blown into existing wall cavities, achieving R-13 to R-15 in a 2x4 wall
• Rigid foam board (XPS or polyiso) installed over sheathing before the siding, adding R-5 to R-10 of continuous insulation and reducing thermal bridging through studs
• Spray foam in open wall cavities when sheathing is removed, providing both insulation and air sealing

Oregon Energy Efficiency Specialty Code encourages insulation upgrades when more than a certain percentage of the wall area is opened up during renovation. We can advise on what triggers those requirements and what the most cost-effective upgrade path is for your home. Pairing a re-side with insulation and weatherproofing improvements often qualifies for Energy Trust of Oregon incentives, which can offset a meaningful portion of the insulation cost.

Portland-Specific Siding Challenges

Portland's climate is uniquely demanding on siding. It is not the total rainfall that causes problems, it is the duration. From October through June, moisture is nearly constant: rain, drizzle, fog, and heavy dew. Walls on the north and east sides of a home may not see direct sun for weeks at a time. This sustained dampness drives several challenges that are less severe in drier climates.

Moss, Algae, and Biological Growth

Moss and algae colonize any surface that stays damp long enough. On siding, this is primarily north-facing walls and walls shaded by trees or neighboring structures. Moss roots can work into gaps between siding courses, prying them apart and creating pathways for water. Algae stains finishes and can degrade paint adhesion over time. Regular cleaning (low-pressure wash, not high-pressure) and selective pruning to improve air circulation are part of siding maintenance in Portland.

Woodpecker Damage

Portland's urban canopy supports a healthy population of woodpeckers, including Northern Flickers. These birds will hammer through wood, engineered wood, and even fiber cement siding looking for insects or creating nest cavities. Cedar and LP SmartSide are the most vulnerable. Fiber cement is more resistant but not immune. If woodpecker damage is a recurring issue on your home, we can discuss deterrent strategies and patch repairs alongside your siding project.

Thermal Cycling and Expansion

Portland's temperature swings are moderate compared to continental climates, but the combination of cool, wet winters and occasional summer heat waves (100-plus degrees in recent years) creates thermal stress on siding materials. Vinyl is the most affected, but all materials expand and contract. Proper gapping and fastening techniques account for this movement and prevent buckling, cracking, or joint failure.

Historic Home Considerations

Portland has thousands of homes in historic districts and conservation districts where exterior modifications, including siding replacement, are subject to design review. The Portland Historic Landmarks Commission, neighborhood associations, and design overlay zones all have input on what materials, profiles, and details are acceptable. In most cases, the expectation is that new siding will match the original material and profile as closely as possible. Cedar lap siding on a Craftsman bungalow cannot be replaced with vinyl. Decorative shingle patterns in gable ends must be replicated.

We have completed siding projects in several of Portland's historic neighborhoods and understand the review process. We can help prepare the application materials, identify historically appropriate materials and details, and coordinate with the review body to keep your project on track. If your home also needs window and door replacement, coordinating both scopes under a single review submission is more efficient.

Siding Repair vs. Full Replacement

Not every siding issue requires a full tear-off and re-side. We perform targeted repairs when the underlying wall assembly is sound and the damage is localized. Common repair scenarios include:

• Replacing a section of lap siding damaged by impact, rot, or woodpeckers
• Re-caulking and re-flashing around windows and doors where sealant has failed
• Replacing deteriorated trim boards at corners, fascia, and window surrounds
• Addressing isolated rot at the base of walls where siding was installed too close to grade
• Fixing improperly lapped or gapped joints that are admitting water

The decision to repair versus replace depends on the extent of damage, the age and condition of the remaining siding, whether the existing siding material is still available for matching, and the condition of the hidden wall components. We will give you an honest assessment. If 30 percent of the siding needs replacement and the rest is on borrowed time, a full re-side is the better investment. If we are talking about a few damaged boards and the rest is solid, a repair makes sense.

What Siding Work Costs in Portland

Siding costs vary based on material, home size, wall complexity (number of corners, windows, and doors), height (two-story walls require scaffolding), and the condition of the existing wall assembly. Here are realistic ranges for a typical Portland-area re-side project on a 1,500-square-foot home with approximately 1,200 square feet of wall area:

• Vinyl siding: $6,000 to $10,000
• Engineered wood (LP SmartSide): $8,500 to $13,500
• Fiber cement (James Hardie): $11,000 to $17,000
• Cedar lap siding: $12,000 to $22,000
• Cedar shingle siding: $15,000 to $27,000

These ranges include old siding removal and disposal, housewrap, new siding and trim, flashing, and caulking. They do not include sheathing repair (if needed), insulation upgrades, window or door replacement, or painting (for materials that require a field-applied finish). We provide detailed, itemized estimates so you know exactly what is and is not included. Request a free estimate to get accurate pricing for your home.

Warranties and What They Actually Cover

Siding warranties can be misleading. Here is what the major product warranties actually include:

• James Hardie (fiber cement): 30-year non-prorated limited warranty on substrate; 15-year warranty on ColorPlus factory finish. Warranty requires installation per Hardie's specifications, which is why hiring an experienced installer matters.
• LP SmartSide (engineered wood): 50-year limited warranty on substrate; 5-year warranty on factory primer. Field-applied finish is not covered by LP.
• Cedar: No standard manufacturer warranty. Longevity depends entirely on grade, installation, and maintenance. Premium CVG cedar installed and maintained correctly can last 50-plus years.
• Vinyl: Varies by manufacturer, typically lifetime limited (prorated after a certain number of years). Covers manufacturing defects but not fading, impact damage, or improper installation.

Boss PDX provides a workmanship warranty on all siding installations covering our labor and installation quality. Product warranties are handled through the manufacturer. We register your warranty and provide documentation at project completion.

Related Exterior Services

Siding projects often overlap with other exterior work. Coordinating multiple scopes into a single project is more efficient and less disruptive than doing them separately. We regularly combine siding with:

• General exterior renovation including decks, porches, and structural repairs
• Window and door installation, which should ideally be done before or during a re-side for proper flashing integration
• Roofing and roof repairs, particularly when the roof-to-wall transition needs reflashing
• Exterior painting for materials that require a field-applied finish
• Insulation and weatherproofing upgrades in the open wall cavities

Frequently Asked Questions

How long does a full siding replacement take?

For a typical Portland single-family home, a full re-side takes 2 to 4 weeks depending on the size of the home, the complexity of the wall geometry, the siding material selected, and whether additional work (sheathing repair, insulation, window replacement) is included. Weather delays are common during the rainy season, so we generally recommend scheduling siding projects between May and October when possible. We can work through the winter, but expect schedule adjustments around sustained rain events.

Do I need a permit to replace my siding in Portland?

If you are replacing siding with the same material type (like-for-like), a BDS permit is generally not required. If you are changing materials, altering the wall assembly (adding insulation or sheathing), modifying openings, or working on a home in a historic or design overlay zone, a permit and potentially design review will be needed. We evaluate permitting requirements during our initial inspection and handle the application process.

What is the best siding material for Portland's climate?

Fiber cement (James Hardie) offers the best combination of moisture resistance, longevity, low maintenance, and cost for most Portland homes. It handles sustained dampness without deteriorating, does not support biological growth, and carries a strong warranty. For homes where the look of real wood is important, particularly historic homes, cedar installed over a rainscreen system is an excellent choice if you are committed to maintenance. LP SmartSide is a strong middle-ground option that gives a wood appearance at a lower cost than cedar with better moisture resistance.

Can I install new siding over my existing siding?

We do not recommend it and generally will not do it. Layering new siding over old siding hides problems (rot, moisture damage, insect infestation, inadequate flashing) and creates a thicker, heavier wall assembly that can cause issues with window and door trim depth, flashing transitions, and fastener holding. It also voids most siding manufacturer warranties. The cost savings from skipping removal are modest, typically $1 to $2 per square foot, and not worth the risk. We remove old siding, inspect and repair the wall, and install new siding on a clean, properly prepared surface.

How do I know if my siding needs replacement versus repair?

Warning signs that suggest replacement rather than repair include: widespread paint failure or peeling across multiple walls, soft or spongy areas when probed with a screwdriver, visible warping or buckling, gaps between siding courses that have opened over time, persistent moisture or mold inside the home along exterior walls, and rising energy bills that suggest insulation or air sealing problems behind the siding. If damage is limited to a small area (one wall section, around one window), repair is usually the right call. We provide honest assessments and will not push a full replacement when a repair will solve the problem.

What happens if you find rot or damage behind my siding?

It gets repaired before new siding goes on. There is no point in putting good siding over bad structure. We cut out and replace rotted sheathing, repair or sister damaged framing, and ensure the wall is structurally sound and properly dried before installing the moisture barrier and new siding. We carry contingency in our estimates for common discoveries, and if the scope of hidden damage exceeds what we anticipated, we discuss the findings and revised cost with you before proceeding.

Is a rainscreen necessary in Portland?

It is not required by code for all installations, but we strongly recommend it for fiber cement and cedar siding. A rainscreen creates a ventilated air gap that allows moisture to drain and dry rather than being trapped against the sheathing. In Portland's climate, where walls can stay damp for months, this drainage plane significantly extends the life of the siding, the sheathing, and the wall assembly. The added cost is $1 to $2 per square foot, which is modest insurance against the most common cause of premature siding failure in the Pacific Northwest.

Get Started on Your Siding Project

Whether you need a full re-side, targeted repairs, or want to understand your options before committing, we start with a free on-site inspection and detailed estimate. We will assess your existing siding condition, discuss material options that fit your home's style and your budget, identify any permitting requirements, and provide transparent pricing with no hidden costs.

Request your free siding estimate online or call us at 844-BOSS-PDX to schedule an inspection. We serve Portland, Beaverton, Lake Oswego, West Linn, Tigard, Tualatin, Milwaukie, Gresham, and surrounding communities throughout the metro area.