Question 1

Is the leak active right now?

Accepted Answer

Active leaks during rain are emergencies and may cost more. If water is coming through the ceiling, place buckets and towels, then call immediately. If it's dry now, schedule a non-emergency inspection — it's cheaper.

Question 2

How old is your roof?

Accepted Answer

Asphalt shingles last 20–30 years, metal 40–70, tile 50+. If your roof is near the end of its life, a roofer may recommend replacement over repair. Knowing the age saves time on the initial call.

Question 3

Can you see the damage from the ground?

Accepted Answer

Missing shingles, sagging spots, or visible flashing damage all help the roofer plan before climbing up. Take photos from the ground and send them ahead — never climb the roof yourself.

Question 4

Do you have attic access?

Accepted Answer

Roofers often inspect from inside the attic to trace leaks. Let them know if access is easy, tight, or blocked by insulation or storage. Clearing a path beforehand speeds up the visit.

Question 5

Has anyone else already looked at it?

Accepted Answer

If a previous contractor gave an estimate or did partial work, share that with the new roofer. It avoids duplicating inspection work and helps them understand the repair history.

Question 6

How much does roof repair cost in Leiden?

Accepted Answer

Roof repair costs in Leiden, ZH vary by scope. Compare local local roofers on HireLocal, read reviews, and get free quotes.

Question 7

How do I find a reliable roofer in ZH?

Accepted Answer

Every roofer on HireLocal is local. See roofers in Leiden, ZH with real ratings and reviews, and get free quotes.

Question 8

How often should I have my roof inspected in Leiden?

Accepted Answer

Most roofing experts recommend an inspection twice a year — in spring and fall — plus after any major storm. Regular inspections catch small issues before they become expensive repairs. Find local roofers in Leiden, ZH on HireLocal and schedule an inspection.

Question 9

What is a Roofing square?

Accepted Answer

A unit of roof area equal to 100 square feet. Roofers use squares to estimate materials and labor. A 2,000 sq ft roof is about 20 squares.

Question 10

What is a Soffit?

Accepted Answer

The underside of the roof overhang (eaves). Soffits are vented to allow attic airflow and can be damaged by moisture or pests. Repair or replacement is often done with fascia.

Question 11

What is a Low-slope roof?

Accepted Answer

A roof with a pitch of 3:12 or less, commonly found on commercial buildings and modern home additions. Low-slope roofs require specific materials (membrane, built-up, or modified bitumen) and drainage systems to prevent ponding water.

Question 12

What is a Roof underlayment?

Accepted Answer

A water-resistant or waterproof barrier material installed directly onto the roof deck beneath shingles or other roofing materials. Provides a secondary layer of protection against leaks from wind-driven rain and ice dams.

Question 13

What is a Asphalt shingles?

Accepted Answer

The most common residential roofing material in the U.S. Made from a fiberglass or organic mat coated with asphalt and mineral granules. Typical lifespan is 20–30 years for standard three-tab shingles and up to 50 years for architectural (dimensional) shingles.

Question 14

What is a Downspout?

Accepted Answer

A vertical pipe that carries rainwater from roof gutters down to the ground or a drainage system. Properly functioning downspouts direct water away from the foundation to prevent basement flooding and foundation damage. Downspouts should discharge at least 4–6 feet from the foundation, either above grade with splash blocks or into underground drain lines.

Question 15

What is a Attic ventilation?

Accepted Answer

A system of intake vents (usually soffit vents) and exhaust vents (ridge vents, gable vents, or powered fans) that allows air to flow through the attic space. Proper attic ventilation is critical for two reasons: in summer, it removes superheated air (attic temps can reach 150°F / 65°C without ventilation) which reduces cooling costs and prevents premature shingle aging; in winter, it keeps the attic cold enough to prevent snowmelt and ice dams. The standard is 1 sq ft of net free area for every 150 sq ft of attic floor (or 1:300 with a vapor barrier). A roofer or HVAC technician can assess ventilation, add vents, and balance the intake/exhaust ratio. Costs range from $300–$600 for adding soffit and ridge vents to $500–$1,200 for a powered attic fan.

Question 16

What is a Drip edge?

Accepted Answer

A metal flashing (typically aluminum or galvanized steel) installed along the eaves and rakes (gable edges) of a roof that directs water away from the fascia board and into the gutter. Without a drip edge, water follows the roof deck edge and wicks back under the shingles or behind the fascia by capillary action, causing rot, mold, and soffit damage that's invisible until it's advanced. Building code (IRC R905.2.8.5) requires drip edge on all asphalt shingle roofs in most U.S. jurisdictions. It's installed under the first course of underlayment at the eaves and over the underlayment at the rakes. Drip edge comes in profiles labeled D, F, or L — type D (or DL) is the most common for residential roofs and has a pronounced kick-out that pushes water into the gutter. Cost: $1–$3 per linear foot for material; labor is minimal when installed during a roof replacement but runs $5–$10 per foot as a retrofit. A missing or improperly installed drip edge is one of the most common code violations found during roof inspections.

Question 17

What is a Soffit vent?

Accepted Answer

An intake vent installed in the soffit (the underside of the roof overhang) that allows fresh outside air to enter the attic. Soffit vents work in tandem with exhaust vents at or near the roof ridge to create continuous airflow that removes heat and moisture from the attic space. Without adequate soffit ventilation, attics overheat in summer (increasing cooling costs 10–20%) and trap moisture in winter (causing mold, rot, and ice dams). Most building codes require 1 sq ft of net free ventilation area for every 150 sq ft of attic floor. Soffit vents come in several styles: continuous strip vents, individual round or rectangular vents, and perforated soffit panels. A common problem is insulation blocking the soffit vents from inside the attic — installing baffles ($1–$2 each) keeps insulation away from the vents. Cost to add or replace soffit vents: $300–$600 for a typical home; included in most new roof installations.

Question 18

What is a Ridge vent?

Accepted Answer

A ridge vent is an exhaust ventilation component installed along the entire peak (ridge) of a sloped roof. It works in partnership with soffit vents at the eaves to create a continuous, passive airflow system: cool outside air enters through the soffit vents, rises as it warms inside the attic, and exits through the ridge vent at the top. This convective loop removes excess heat in summer and moisture-laden air in winter, protecting the roof deck, insulation, and framing from damage. Ridge vents are considered the most effective exhaust vent type because they ventilate evenly along the full length of the roof rather than at isolated points like box vents or turbine vents. Most modern ridge vents are low-profile shingle-over designs that are nearly invisible from the ground, preserving curb appeal. They include an internal baffle that prevents rain, snow, and insects from entering while still allowing air to pass freely. Building codes typically require 1 square foot of net free ventilation area per 150 square feet of attic floor (or 1:300 with a vapor barrier). A standard ridge vent provides about 18 square inches of net free area per linear foot. Materials cost $2 to $4 per linear foot for the vent itself; professional installation during a re-roof adds $400 to $800 for a typical home. Retrofitting a ridge vent onto an existing roof costs $800 to $1,500 because the roofer must cut a slot along the ridge and re-shingle around the vent. Common issues include clogged baffles from attic insulation blown too close to the ridge, cracked or lifted shingles over the vent, and improper installation that allows water infiltration. A qualified roofer should inspect ridge vents during routine roof maintenance every 3 to 5 years.

Question 19

What is a Roof pitch?

Accepted Answer

Roof pitch is the measurement of a roof's steepness, expressed as a ratio of vertical rise to horizontal run — for example, a 6/12 pitch means the roof rises 6 inches for every 12 inches of horizontal distance. Pitch is the single most important factor in selecting roofing materials, estimating labor costs, and planning drainage. Low-slope roofs (below 3/12) require membrane roofing systems like TPO, EPDM, or built-up roofing because shingles cannot prevent water infiltration at shallow angles. Standard asphalt shingles work on pitches from 4/12 to 12/12, which covers the vast majority of residential roofs. Steep pitches above 8/12 require additional fasteners and sometimes adhesive to prevent shingle blow-off, and they increase labor costs by 20–50% because roofers need specialized safety equipment, toe boards, and roof jacks. Pitch also affects material quantity: a 12/12 pitch roof covers about 41% more surface area than a flat roof with the same footprint, requiring proportionally more shingles, underlayment, and flashing. When getting roofing estimates, always verify the roofer has accounted for your actual pitch — an estimate based on satellite imagery sometimes miscalculates pitch, leading to surprise change orders. Roof pitch also determines attic ventilation requirements and snow load calculations in cold climates. You can measure pitch yourself from inside the attic by holding a level horizontally against a rafter and measuring the vertical distance at the 12-inch mark.

Question 20

What is a Roof truss?

Accepted Answer

A roof truss is a pre-engineered structural framework — typically made from dimensional lumber connected by metal plates — that supports the roof and transfers its weight to the exterior walls. Trusses are manufactured off-site to precise specifications and crane-set onto the wall plates, making them faster to install than traditional stick-framed rafters. Common residential styles include king-post, Fink, and scissor trusses. Because trusses are engineered as a system, cutting, notching, or modifying any member without an engineer's approval can compromise structural integrity — this is a frequent code violation in DIY attic conversions. A licensed roofer or carpenter should handle any truss-related repairs, replacements, or reinforcements. Typical reasons homeowners need truss work: storm or wind damage, sagging rooflines, termite damage, or adding load for solar panels. Repair costs range from $500–$5,000+ depending on damage extent.

Question 21

What is a Standing seam metal roof?

Accepted Answer

A standing seam metal roof is a premium roofing system where long metal panels run vertically from ridge to eave, joined by raised interlocking seams that stand 1–2 inches above the flat panel surface. The seams are either mechanically crimped or snap-locked together, creating a continuous waterproof barrier with no exposed fasteners. Materials include galvanized steel, Galvalume (steel coated with aluminum-zinc alloy), aluminum, copper, and zinc. Standing seam roofs last 40–70 years (vs. 20–30 for asphalt shingles), reflect solar heat reducing cooling costs by 10–25%, resist wind up to 140 mph, and are virtually maintenance-free. They're also the best roof type for solar panel mounting since clamps attach directly to seams without penetrating the roof. Installation costs $10–$18 per square foot ($1,000–$1,800 per roofing square) — roughly 2–3× the cost of architectural shingles. Not all roofers install metal; look for contractors with specific standing seam experience.

Question 22

What is a Ridge cap?

Accepted Answer

A ridge cap is the row of specially shaped shingles, tiles, or metal pieces installed along the peak (ridge) of a roof where two sloping surfaces meet. Its primary job is to weatherproof the ridge line — without it, the ridge opening would allow rain, snow, and wind-driven debris directly into the attic. Ridge caps also contribute to attic ventilation when used with a ridge vent: the cap shingles cover the vent opening while still allowing hot, moist air to escape. For asphalt shingle roofs, manufacturers sell pre-bent ridge cap shingles (about $30–$60 per bundle, each covering 20–33 linear feet) designed to fold over the ridge cleanly. On metal roofs, a formed metal ridge cap panel snaps or screws into place. Signs of failing ridge caps include cracked, curled, or missing cap shingles; visible daylight from the attic at the ridge; and leaks near the top center of ceilings. Ridge cap replacement is a straightforward repair for a roofer, typically costing $300–$700 for labor plus materials on a standard-size home.

Question 23

What is a Roof flashing?

Accepted Answer

Thin pieces of galvanized steel, aluminum, copper, or lead installed at roof transitions and penetrations — valleys, chimneys, skylights, vent pipes, dormers, and wall-to-roof junctions — to direct water away from seams and prevent leaks. Flashing failures account for an estimated 90% of all roof leaks. Types include step flashing (L-shaped pieces woven into shingle courses alongside a wall), counter flashing (embedded in masonry above step flashing), valley flashing (W-shaped metal running down a roof valley), drip edge (installed at eaves and rakes), and pipe boot flashing (rubber or neoprene cones around plumbing vents). Proper installation requires overlapping upper pieces over lower ones so gravity carries water across the joint. Common failure points: rusted-through galvanized steel (15–20 year lifespan), dried-out roofing cement used as a substitute for proper flashing, and lifted or wind-damaged flashing at chimney corners. Repair costs range from $200–$500 for a single flashing replacement to $1,000–$3,000 for full chimney reflashing.

Question 24

What is a Ice and water shield?

Accepted Answer

A self-adhering, rubberized asphalt membrane installed on a roof deck beneath shingles in areas vulnerable to ice dams and wind-driven rain — typically along eaves (first 3–6 feet from the edge), in roof valleys, around chimneys, skylights, and plumbing vents. Unlike standard roofing felt or synthetic underlayment, ice and water shield seals around nail penetrations, creating a watertight barrier even when water backs up under shingles from ice dams. Most building codes require it in climate zones where the January mean temperature is 25°F or below — which covers most of the northern US. The material costs $80–$200 per roll (65–75 sq ft coverage) and adds $500–$2,000 to a roofing project depending on how much is needed. It is not a substitute for proper attic ventilation and insulation (the real ice dam prevention), but it's a critical last line of defense. Common brands include Grace Ice & Water Shield, GAF WeatherWatch, and CertainTeed WinterGuard.

Question 25

What is a Roof inspection?

Accepted Answer

A systematic evaluation of a roof's condition performed by a licensed roofer, home inspector, or structural engineer. A thorough inspection covers shingles or roofing material (missing, cracked, curling, granule loss), flashing (around chimneys, vents, skylights, and valleys), gutters and downspouts, soffit and fascia, attic ventilation, signs of water intrusion from inside the attic, and structural decking. Cost: $150–$400 for a standard visual inspection; $300–$600 if drone or infrared thermal imaging is used to detect hidden moisture. Homeowners should schedule a roof inspection every 2–3 years, after major storms, before buying a home, and when the roof approaches 15–20 years of age. Insurance companies increasingly require roof inspections before issuing or renewing homeowner's policies. The inspection report grades the roof's remaining useful life and identifies urgent repairs vs. items to monitor. Many roofing companies offer free inspections, but independent inspectors provide unbiased assessments without the incentive to sell repairs. A roof inspection can prevent small $200–$500 issues from becoming $5,000–$15,000 failures.

Households	70,487
Owner-occupied share	41 %
Jobs per year (roofer)	2,705
Pros the market supports	59
listed on HireLocal	11
Coverage	19 %
Score	91 / 100

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