What Does a Structural Engineer Do? Everything You Need to Know.
Structural engineers focus on the physical integrity and design of projects such as buildings, bridges, and tunnels. It is their job to make sure the physical structure maintain integrity and are able to handle the loads and forces they encounter.
Some structural engineers focus solely on building projects for commercial, residential, and townhome/condo associations.
This facet of the industry encounters unique projects and works with a wide variety of clients such as homeowners, homeowner associations, Realtors, contractors, architects, and designers just to name a few.
These are areas of work a structural engineer may be involved in:
Home Purchase Transactions
Additional Structural Needs
Residential Building Projects:
Many people do not realize they need a structural engineer for their building project until a city official or other professional requests it.
So how does a structural engineer fit into the puzzle?
A structural engineer is typically required whenever there are (1) structural changes made to an existing structure (2) when a new structure is being designed.
Structural changes to existing structure:
Let’s say a homeowner is looking to add-on to their home or hope to remove a load bearing wall to make a kitchen / great rooms.
The size of the project will dictate the proper course of action. Major renovations or additions will require a plan from an architect or designer while a minor renovation may eliminate that step all together.
However, both minor and major renovations/additions typically require a structural engineer.
It’s crucial that your structural engineer understands all aspects of building construction including thermal technology and entire home performance as well as structural components.
Once the homeowner or condominium / townhome association has general idea of their budget, goals, and timeline they will need to hire a designer and/or architect to design a plan for their renovation.
In a nutshell, this plan will provide the client with layouts, dimensions, and construction notes/details.
On top of this, it is imperative that your architect or designer works with a structural engineer at the onset of your project.
The missing piece on the plan is something only a structural engineer can provide, the load carrying structural system including: live load, dead load, and environmental loads such as wind, thermal, and seismic.
The engineer will analyze the plan, perform calculations, and add these details to the architectural plan. Once the plan is complete, a contractor can begin work.
Many structural engineers would consider minor renovation to be something like removing a load bearing wall between the kitchen and great room.
Typically, you will NOT need an architectural plan for this. Since a plan is not needed, the owner would go straight to a structural engineer who has working relationships with contractors, architects, and designers.
In order for your contractor to remove the wall, a structural engineer will typically need to determine if the wall is load bearing via an engineering inspection on-site.
If the wall is load bearing, the engineer will need to design a beam & column system to replace the wall being removed. Often times, an engineering report describing the beam & column system along with a scope of work will be provided to the homeowner.
The contractor can use this report to obtain a building permit from the city and proceed with the load bearing wall removal. If you are pulling a permit, 9 times out of 10, this report is all the city official will require.
Some building officials and/or inspectors require a drawing from the engineer in order to get the building permit, which can mean additional charges.
Engineering for new structures:
If an individual is looking to build a home there are many design/plan resources at their fingertips.
Most people know they need an architectural plan and design, but don’t know where to begin with obtaining one.
They also don’t realize that a structural engineer is often required (or highly recommended) to review or add detail to plans.
Listed below are 2 examples of architectural plans one can secure from either an architect or through an “on-shelf” drawing catalog. Also note the importance of a structural engineer’s role is in the building process from the start!
Standard House Plan:
A standard architectural plan for a house typically will not require engineering up front. Because these plans are common, many lumber yards can provide you with the proper elements for the load carrying structural system.
With this being said, it is a good idea to have a structural engineer look over the plan before materials are ordered and work begins on the project.
If building elements are undersized by mistake, it can be a costly and regrettable expense to the homeowner / builder. For example, one structural engineering firm received a phone call from a customer stating that their brand-new granite countertops were pulling away from a wall.
The homeowner was frustrated and confused because their counter tops were only recently installed. An engineer was dispatched to investigate the issue and discovered that the floor joists were structurally sound but were positioned non-traditionally allowing for deflection/settlement to occur.
The verdict was that the joists needed to be reinforced in order to prevent the expensive granite countertops from cracking at the owner’s expense.
The original architectural plan was designed to support lighter materials, not the heavy load of granite countertops, the lumber yard had simply provided the structural materials the plan called for and the contractor installed the joists the way the plan stated.
This is just one example of how materials like hardwoods, granite, and tile can affects loads. Had the homeowner in this situation known to have a structural engineer look over their plans from the onset, the whole issue could have been avoided.
As you can tell, making a structural engineer a key player in your initial planning is a top priority!
Custom House Plan:
If you have envisioned your dream home for some time, you may choose to build a custom home. In this case, you will work with an architect and/or designer whom will draw up plans for you.
Because the plan is one-of-a-kind, it is recommended that a structural engineer work with the architect on these plans to develop the proper structural framework.
Your architect may be able to refer you to structural engineer they have worked with previously or you may use your own contact.
Engineering for Commercial Buildings
When it comes to commercial projects, renovations or new-construction, structural engineers are not just recommended, they are required and essential.
Typically, the architect heading up the commercial project will hire a structural engineer to work directly with them in the project.
The structural engineer is responsible for all the structural aspects of the project such as:
Before any design work begins, a structural engineer will be involved with the initial site investigation to determine if the soil is conducive to the project at hand.
Certain soils or landscape could be the downfall to a project’s success.
A structural engineer can use their expertise to verify that the build-site is suitable for the requirements of the approaching project or if soil corrections will need to be made.
A structural engineer will work closely with the architect/design team to develop detailed construction plans.
They tackle specific aspects of the plan such as selecting appropriate job materials, foundation design, header/beam sizing, live load, dead load, and environmental loads such as wind, thermal, and/or seismic and how all these stresses affect the building.
Also, safety regulations will be considered. This is a critical part of the process and will require a team of professionals working together to ensure a comprehensive and final plan.
Once the construction site has been given the green light, and the plans are completed, there is still work to be done.
The structural engineer is a viable resource to the whole team throughout the building stage.
Often times, they will supervise the various project teams, ensure legal guidelines, environmental directives, and health/safety requirements are met, and provide progress reports to management or clientele.
Engineering Inspections for Home Purchase Transactions:
It’s common knowledge that a traditional home inspection is a good idea when it comes to buying or selling a home.
Sometimes, that is all a buyer may need for peace of mind. This type of inspection prior to a home purchase transaction will typically cover the condition of the home’s heating system; central air conditioning system (temperature permitting); interior plumbing and electrical systems; the roof, attic and visible insulation; walls, ceilings, floors, windows and doors; the foundation, basement and basic structural components.
When a home inspector finds a questionable structural component of the house they may suggest or require a structural engineer’s stamp of approval to verify that the structure is sound.
This happens frequently with foundations. The inspector may notice some larger cracks in the foundation or perhaps it appears to be bowing out in an area.
The inspector may not be comfortable with the size of those cracks and will want a second opinion from a structural engineer. The structural engineer will perform a visual inspection of the foundation and/or provide a scope of repair in the form of an engineering report.
This report can be used to get bids on any necessary repairs and/or to obtain a building permit. An engineer’s report holds authority and is deemed most credible.
This report is highly beneficial to a home buyer as it can help with purchase price reductions, officially verifies structural issues and scope of work to repair, helps speed up the closing process, and can bring peace of mind to sellers and buyers alike.
Structural engineers are often involved in both residential (single family, condominiums, townhomes) and commercial construction defect cases.
Construction defect can mean faulty design, defective materials or poor craftsmanship and failure to adhere to applicable building codes from the construction company.
Determining a final verdict can be a lengthy process because there are often many parties involved such as lawyers, insurance companies, structural engineers, construction companies and other vendor/specialists.
A structural engineer has a very specific role in a construction defect case depending on if they are on the plaintiff or defendant side.
They are either involved to prove that issues are present (plaintiff) or that no or minimal issues exist (defendant). Typically, structural engineers are hired on by the construction defect law firm.
They will communicate with the lawyers providing structural engineering expert advice and forensic investigation findings as the case is built.
First, the engineers must familiarize themselves with the case by reading any existing literature or reports on the issues at hand.
Next steps would include all party walk throughs where “all parties” can familiarize themselves with the site via a visual tour, any further investigations necessary for the engineers to view essential components of the building, research, analysis and reporting.
The structural engineers will work closely with the layers during the reporting phase to ensure all the appropriate information has been included in the report. This report will either be used to help settle the case outside of court or, if an agreement cannot be made, will be brought to trial.
If the case does come to a trial, the structural engineer will often be asked to take the stand as an expert witness.
Structural engineers are also involved in both residential and commercial storm damage cases where catastrophic events such as tornadoes, hurricanes, hail, wind, or earthquakes may have caused property damage.
There are two ways they could be involved: hired directly by an insurance company or third party company hired by the property owner.
If a property owner believes they have storm damage, they will typically file an insurance claim. They either hire an engineer off-the-bat to strengthen their case from the start (not as common) or they hire a structural engineer to fight the insurance company if their claim gets denied.
If a claim does get denied, but the property owner feels strongly that damage is present, their insurance company may suggest that a structural engineer (whom they choose) come look at the property.
As the property owner, it is best to hire your own third-party structural engineer to avoid bias. There are too many cases of property owners getting taken advantage of because the insurance company provided their own structural engineer to their own benefit.
Once the property owner hires a third-party structural engineer, they will inspect the site, take notes/photographs/measurements, and provide the homeowner with an analysis and report depicting their findings.
The property owner can use the report to fight the insurance company and hopefully win the claim.
Additional Structural Needs:
Potential Structural Component Fail
There are times when a structural engineer may be needed even when a client has no intentions of building a house or renovating one.
This may happen if a homeowner suspects that a structural element within their home is failing. Some potential threats are wall cracks, uneven/sagging floors, foundation cracks/bowing, sagging/shifting decks, cracked beams, doors that stick, or standing water in the basement.
All of these scenarios may be indicative of a hidden problem within your home.
Having an engineer inspect the area can prevent further damage from occurring and provide homeowners with peace of mind.
Solar Panel Install
Adding solar panels to a commercial, residential, or townhome/condo complex is fairly common today.
However, it may require a structural engineer to determine if the building or complex can handle the additional loads/uplift factor from the solar panels. If this is the case, a structural engineer will perform an inspection of the roof, perform calculations, and generate a report which will include their findings.
If the engineer finds that the roof needs to be reinforced to handle the additional loads, they can provide a scope of work or even a drawing if necessary.
Have you been suspicious of your existing deck? Has it begun to sag or show signs of settlement? If you are feeling uneasy, it is a good idea to have a structural engineer inspect the deck.
They can check to make sure the deck was built to code, looking for things like appropriate footings, soils, supports, fasteners, etc.
Are you looking to install any of the following: hot tub, aquarium, granite countertops, whirlpool tub, piano, pool tables?
The items above add loads to your home that may be above and beyond what your joists can handle (we talked about this idea earlier under the section about new construction and standard house plans).
This is most often true if you have an older home. In general, the rule of thumb is to have a structural engineer inspect the area to ensure the additional live loads are within the allotted parameters.
For instance, if you are looking to install a fish tank that holds 400 gallons of water (1 gallon of water weighs about 8.34lbs), you will be adding about 3,336.00 lbs to your floor joists. An additional load, such as this, may require reinforcements on the floor joists.
A structural engineer has the ability to inspect the area, perform calculations, and provide you with a report/scope of work if reinforcements are necessary.
Accidental Structural Modifications
Sometimes, during remodel projects, an HVAC, home flipper, plumber, or electrical professional may accidentally cut into a structural component such as a header.
This can be very serious and detrimental to the structural integrity of your home. A structural engineer should perform an inspection as soon as possible.
They will perform calculations to determine the best solution for the compromised area.
Moisture Issues/Sump Pump Running Constantly
Some structural engineers have knowledge and experience with moisture intrusion in the form of leaks, ice dams, attic condensation “sweating”, window/door leaks, standing water in a basement, freeze/thaw cycles, and other drainage issues.
If you are having water issues be sure to ask your structural engineer if they can help.
Hopefully this blog provided you with some basic information on what structural engineers actually do. As we cited throughout the article, there are many situations when decision makers are unaware that structural engineers are required or could be beneficial to a project.
Whether you are looking to start a residential or commercial renovation or new-build, need an engineer for the sale of your home, think you may need to open a construction defect case, are suspicious of a potential structural failure within your home, incorporating additional loads such as a hot tub/fish tank, or had a property fall victim to a storm, structural engineers are typically involved and can help.
Make the call to contact a structural engineer first before you start a project. They will let you know if their role is applicable.