EM Construction provides expert lintel and sill repair and replacement services for residential and commercial properties throughout New York and New Jersey. Deteriorated lintels and sills are among the most common — and most consequential — structural deficiencies found on New York City buildings.
Lintels and sills are structural masonry components that frame windows and doors. Lintels span the opening above, carrying the load of the masonry above the window or door. Sills sit below the opening, directing water away from the frame. When either element fails, the consequences range from water infiltration and interior damage to cracked facades and, in severe cases, structural instability.
Understanding Lintel & Sill Failure
Steel lintels are the most common type found in New York City’s brick buildings. Over time, moisture penetrates mortar joints and causes the embedded steel to corrode. As rust forms, it expands — up to eight times the volume of the original steel — pushing surrounding brick outward and causing visible cracking and bulging. If left unaddressed, the lintel can fail entirely, creating a safety hazard and requiring far more extensive repairs.
Stone sills crack from freeze-thaw cycling and settlement. Precast concrete sills deteriorate when protective coatings fail and water contacts the embedded reinforcement. Wood sills — common in older buildings — rot when waterproofing fails at the sill-frame junction.
Our Lintel Services
Steel Lintel Replacement
We remove deteriorated steel lintels by temporarily shoring the masonry above, cutting out the failed lintel, and installing a new hot-dip galvanized or epoxy-coated steel lintel to prevent future corrosion. Disturbed brick is then reset and repointed.
Lintel Stabilization
When a lintel is structurally intact but showing surface corrosion, we can clean, treat, and coat the lintel to halt corrosion progress, then repoint surrounding joints and install elastomeric flashings to prevent further water access.
Precast Concrete Lintel Installation
In appropriate applications, precast concrete lintels offer a corrosion-free alternative to steel. We install precast lintels designed to the structural requirements of each opening.
Our Sill Services
Stone Sill Repair & Replacement
Cracked or broken stone sills are repaired with epoxy structural adhesives and patching compounds, or replaced entirely with new bluestone, granite, or precast concrete sills bedded in mortar and sealed at all joints.
Precast Concrete Sill Installation
Precast concrete sills are durable, cost-effective, and available in profiles that match original stone sills on historic buildings. We install precast sills with proper mortar setting and sealant at all perimeter joints.
Metal Sill Pans
Where windows are being replaced, we install concealed metal sill pans — aluminum or stainless steel — beneath the new window unit to intercept and drain any water that penetrates the window frame, preventing damage to the wall assembly below.
Sill Caulking & Waterproofing
Even sound sills require proper sealant maintenance at their perimeter joints. We rake out failed caulk, install backer rod, and apply high-performance elastomeric sealant at all sill-to-masonry interfaces.
Common Warning Signs of Lintel & Sill Failure
– Stepped or diagonal cracks in brick above or beside windows and doors
– Visible rust staining below window openings
– Brick courses that are bowed, displaced, or bulging near window heads
– Cracked or missing sill sections
– Water stains on interior walls below windows after rain
– Failed or missing caulk at sill perimeter joints
Local Law 11 / FISP Compliance
Lintel and sill conditions are closely scrutinized during New York City’s mandatory FISP (formerly Local Law 11) facade inspections. EM Construction performs the lintel and sill repairs required to resolve unsafe or safe-with-repair conditions noted in FISP reports, and we coordinate with filing engineers to document the work for DOB submission.
Our Process
1. Assessment — We probe and test lintels and sills to determine the extent of deterioration.
2. Temporary Shoring — Masonry above the opening is shored to support loads during lintel replacement.
3. Removal — Failed lintels or sills are removed along with disturbed brick or stone.
4. Installation — New lintels or sills are installed to structural requirements with proper bearing and flashing.
5. Masonry Restoration — Surrounding brick or block is reset, repointed, and cleaned.
6. Sealing — All perimeter joints are sealed with appropriate elastomeric sealants.
Service Areas
EM Construction serves all five New York City boroughs, Long Island, Westchester County, and northern New Jersey.
Get a Free Estimate
Lintel and sill repairs are time-sensitive. Contact EM Construction today for a professional assessment and free estimate before minor damage becomes a major structural problem.