L+M Structural offers a dynamic mix of services: comprehensive expertise in the repair and upgrading of existing structures with the forward thinking design of structures for new buildings. Indeed, it’s our work with aging buildings – how we preserve, restore and upgrade them – that makes us that much more knowledgeable and expert in the design of new structures. We know what works and what doesn’t.

Our success with existing buildings includes the full range of structures, those from the last several decades as well as much older buildings whose systems, materials and methods are no longer in use. We conduct a painstaking investigation of each system, exploring what makes it work and why it has failed. The solution we develop will serve over the long term, and we will advise on a maintenance program so the building continues to perform.

Since L+M is a collaborative AE firm, clients also benefit from the input of L+M’s architectural, electrical, and mechanical and plumbing engineering groups. They too are experts in renewing older buildings and will consult with the structural team as needed.

Feasibility studies

Our clients don’t like surprises, so we recommend a feasibility study as the essential first step with any project. It outlines the project’s scope, requirements, challenges and cost and lets the client make an informed go/no-go decision. Because of our experience with all type and ages of buildings, L+M Structural studies can be more comprehensive than most. We know what to look for and, when a condition is found, what the implications are.
That’s true whether we are conducting a stand-alone study of the structure or are part of a larger L+M team investigating what it will take to renew all aspects of the building.

New Residential and Commercial Building Projects

When designing for new buildings, L+M Structural first advises on which structural system will work best. Working with either an independent architecture firm or our in-house team, we create efficient, cost conscious structures, selecting the right materials and putting them to the most effective use.
Having worked with aging structures, we’ve seen the wear and tear building systems experience and can design solutions that anticipate future problems and minimize maintenance costs.

Major Alterations/Additions

Whether the project is a gut renovation or a significant addition, L+M Structural provides expert help. We bring a surgeon’s precision to these complex projects, extending or reusing a structure while maintaining its original integrity. Because we work daily with all kinds of building challenges, we bring a knowledgeable eye to a structure’s current demands and opportunities, and how it can be reconfigured or expanded.

Structural Restoration and Repair

To get a building back to structural soundness, we start with a thorough investigation of its condition. A visual inspection comes first, followed by a sound analysis, and then by probes and bores into the building envelope to understand the nature of the damage and its cause. Often the culprit is salt and water but it can be faulty construction, poor maintenance, or the use of the wrong material.
We then come up with a phased program of repairs to restore the structure’s integrity without affecting its daily use. So that repairs last the life of the building, we recommend and design a thorough maintenance program.

Parking Structure Restoration

L+M Structural solves the complex challenges of repairing and restoring parking garages, while minimizing the impact on daily operations. Once we’ve determined the project scope and completed the feasibility study, we develop a schedule that outlines how to do the work in phases without inconveniencing patrons. We also devise a safety plan that incorporates barriers and other measures to assure user safety during construction

Sidewalk Replacement and Sidewalk Vault Repair

Sidewalk and sidewalk vault repair and replacement is relatively straightforward, remediating the damage that can come from salt and water, accumulated wear and tear, and other stresses. The true challenge is meeting all the requirements of New York City agencies with oversight of city streets. And that’s why our staff includes expeditors who have relationships with all of the city agencies and entities that may have a say on what gets done and how. They include, in New York City, the DOT, DOB, LPC, Parks, MTA and Con Ed


We create and repair such site elements as sidewalks, curbs, playgrounds, retaining walls, and courts for sports such as basketball and tennis. We can design them from the beginning or investigate and make repairs where damage has occurred. With every assignment, our standards are quality, durability and safety.

Plaza Restoration

Our plaza restoration projects range from the renewal of an entire plaza space and all its elements to the rehabilitation of single components such as sidewalks. Plaza projects become more complex when they are on top of a parking garage or other structure. First comes the removal of everything down to the below-surface deck, followed by the repairing of the deck, and then the installation of a new waterproofing membrane.
Other necessary elements are the accommodation of electrical, plumbing, drain piping, and landscaping. Finally, there is the reintroduction of amenities and finishing planters, decks, and play surfaces,

Building Envelope Restoration

The repair and restoration of the building envelope can include the upgrade of such structural elements as leaking roofs and balconies that may have become unsound.
In those cases we can reinforce the balcony and address other problems and do a careful inspection of the roof to identify leaks and the best kind of repair.

Historic Restoration

Our knowledge of all US structural systems both past and present means we understand how each works and the best way to return the system to optimal condition. That’s essential to assuring an authentic restoration process and project.

Structural Strengthening/ Rehabilitation/Adaptive Re-Use

As buildings age, they may be put to new uses or, in the case of a vertical expansion, have to accommodate and additional load. Whatever the situation, we’ll measure what additional load the current structure can tolerate if any, and, when necessary, strengthen the structure to take on additional stress and weight.

Capacity Investigation

In this investigation we analyze what is the current capacity of structure, how much is unused, and how much can be added.

Building condition reports

As part of an overall building assessment, we will review the current state of the building’s structural system, note what repairs and upgrades are needed, and create a realistic schedule, based on need and degree of difficulty, for repairs.