Recurring leaks around flashing, seams, penetrations, or roof-to-wall joints can be frustrating to track down, especially when you cannot see where the water is getting in. Instead of covering the entire surface without finding the cause, we inspect the vulnerable details, trace the likely entry point, and apply the right sealant or repair where it is actually needed.
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Call (917) 268-3699 for a Free InspectionPlaceholder — targeted sealant work around flashing and seams
When water gets into a building, the open field of the roof isn't always the first place to look. Seams, flashing, joints, penetrations, and roof-to-wall transitions can deteriorate long before the surrounding surface shows obvious failure. Over time, small gaps can develop around chimney flashing, HVAC curbs, pipes, skylights, parapet walls, and membrane joints.
Our approach starts by finding the vulnerable point rather than simply covering the entire surface. We inspect the existing materials, determine how moisture is entering, and recommend the appropriate repair or protective treatment for the condition we find.
Visit Our Homepage Get a Free Sealant InspectionThis is a targeted moisture-protection treatment applied to joints, seams, flashing, penetrations, and other areas where water can enter a roof assembly. Unlike a full-surface restoration system, this type of work focuses on the details.
However, the material appropriate for a metal flashing joint may not be the same product selected around a masonry transition or membrane penetration. The goal isn't simply to add another layer. It's to create a durable barrier at the places most likely to allow moisture into the building.
| Full Roof Coating | Targeted Sealant |
|---|---|
| Protects the larger surface | Protects specific problem areas |
| Helps resist weather and UV exposure | Seals joints, seams, and penetrations |
| Covers the main roof field | Reinforces flashing and transitions |
| Best for broad surface protection | Best for localized leak points |
A complete system and targeted repairs often work together. A well-protected surface can still leak if damaged flashing, joints, or penetrations are left untreated.
Flashing creates a transition between different building materials. These transitions can become vulnerable as materials expand, contract, age, or separate. We inspect flashing for gaps, deterioration, failed joints, and areas where previous repairs have lost adhesion.
Roofing materials meet at seams, creating another potential path for moisture. This is particularly important on membrane, modified bitumen, and metal roof assemblies. Where the existing materials remain suitable for repair, targeted joint treatment can reinforce vulnerable areas.
Pipes, HVAC equipment, conduits, vents, and other rooftop equipment create openings through the roof assembly. Each penetration needs to be examined individually. Movement around equipment, aged materials, and deteriorated detailing can create gaps that allow water beneath the surface.
NYC's low-slope buildings frequently feature historic brick parapets wrapped in clay tile or terracotta coping. Water can bypass the roof entirely by entering through degraded mortar joints on the parapet's exterior face. We install heavy-duty liquid flashing systems up the vertical wall and beneath the coping, following applicable NYC DOB requirements for the building and repair conditions.
We'll inspect the details most likely to allow moisture into your building and explain what we find.
Polyurethane products can provide strong adhesion and flexibility and may be appropriate for particular joints and gaps. Because different formulations have different exposure limitations, product selection depends on the location and manufacturer's requirements.
Silicone products offer strong flexibility and weather resistance and can be useful around certain flashing, metal, and exposed joints. Compatibility with the existing substrate remains essential.
Butyl and rubberized materials can be useful for particular seams and detailing applications where their characteristics match the existing roofing materials and exposure conditions.
Treating vulnerable details is not a substitute for addressing deterioration across the broader roof assembly. Likewise, applying a new surface layer over a failed seam doesn't eliminate the underlying problem.
During restoration projects, we inspect critical details before work begins. Where appropriate, we reinforce seams, flashing, penetrations, and transitions before addressing the larger roof surface. This creates a more complete approach: protect the field and address the details that could allow water around it.
View Our Roof Inspection ServiceWe begin by examining seams, flashing, penetrations, joints, parapet transitions, drainage conditions, and visible moisture entry.
Not every damp area originates directly above the visible stain. We look for the likely entry point rather than assuming the first visible symptom is the source.
Successful adhesion depends heavily on preparation. The area is cleaned and prepared according to the requirements of the selected material.
The chosen material is installed according to the manufacturer's requirements, with attention to joint dimensions, adhesion, coverage, weather conditions, and surrounding materials.
We check treated areas for coverage, adhesion, detailing, and visible defects before completing the project. The exact timeline depends on the number of locations, accessibility, preparation requirements, weather, and curing conditions.
Placeholder — inspecting and sealing vulnerable roof details
Focuses on high-rise commercial setbacks, multi-tiered roof terraces, and sealing complex penetrations around structural steel HVAC dunnage beams and commercial bulkheads.
Prioritizes historic rowhouses and brownstones in neighborhoods like Park Slope and Bed-Stuy. Critical work can include sealing the vulnerable party-wall seam where your roof meets an adjoining building's roof system.
Addresses a mix of attached multi-family brick properties and commercial warehouses. We specialize in sealing worn valley seams on tin roofs and flashing around aging residential skylights.
Handles mid-century apartment blocks and industrial properties. Work typically focuses on reinforcing structural expansion joints and large, cast-iron drain scuppers that experience heavy volume.
Features more detached commercial and suburban structures requiring specialized flashing sealants around complex valley transitions, chimney bases, and wood-to-masonry framing lines.
Often, yes. A surface restoration system protects the broader roof area, while individual seams, flashing, penetrations, and transitions may require separate attention. We inspect these details and recommend additional work only where it is appropriate.
It can resolve leaks caused by certain deteriorated seams, flashing points, and penetrations. However, an active leak may also be caused by membrane failure, drainage problems, saturated materials, or structural conditions. Those issues require the appropriate repair rather than simply treating the visible entry point.
There isn't one lifespan that applies to every application. Performance depends on the product, substrate, UV exposure, movement, joint conditions, weather, preparation, and workmanship. During an inspection, we can explain what factors are likely to affect the treated areas on your property.
Sometimes. If the broader roof remains in good condition and the problem is isolated to particular details, targeted work may be sufficient. If the roof surface itself is deteriorating, a larger restoration or repair strategy may be more appropriate.
Common trouble spots include chimney and vent flashing, membrane seams, expansion joints, pipe penetrations, HVAC curbs, skylights, parapet transitions, and roof-to-wall connections.
There is no meaningful flat rate because projects vary considerably. Pricing depends on the number of locations, accessibility, existing conditions, preparation, materials, and whether additional repairs are required. We provide a project-specific estimate after inspection.
Get a Free Waterproof Sealant Inspection
Don't wait for a small roof detail to become an interior water problem. We'll inspect the areas most likely to allow moisture into your building, explain what we find, and recommend the appropriate next step for your roof.
Get a Free InspectionCall (917) 268-3699
This page is provided for general informational purposes only and does not constitute legal, engineering, architectural, or compliance advice. Waterproof sealant performance and lifespan can vary based on product formulation, substrate condition, surface preparation, joint movement, UV exposure, weather, and workmanship. Building owners should confirm project-specific requirements with the system manufacturer, a licensed professional, and the NYC Department of Buildings as applicable.
A roof coating is a system applied to an existing roof that has to be properly evaluated, prepared, repaired, and matched with the right coating technology.
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