To the uninitiated, a lot of everyday building construction with wood framing and concrete foundations looks pretty similar. However, from a structural engineering design perspective, they could be quite different. Light commercial and multifamily buildings, as well as many custom homes, are more complex and subject to greater load demands and code requirements than simple one- and two-family homes. The design of some or most of the structural systems in these structures must be designed based on calculations so that they perform as required under the anticipated loads, rather than conforming to traditional practices prescribed by the residential code. It is normal for the construction documents for these projects to include structural engineering drawings to communicate to the contractor how engineered structural components and systems fit together.
In the residential and light commercial construction sectors, some contractors do not seem to know what to do with structural drawings. The apparent similarity of engineered construction to traditional residential construction results in certain contractors failing to understand how they are different. Not knowing what they are taking on, they may be less expensive than their more sophisticated counterparts and are more likely to secure projects with inexperienced owners. This doesn’t always end well. Continue reading “Will Your Contractor Read the Drawings?”
Distressed or malperforming foundations are among the most troubling and potentially expensive issues a homeowner (or buyer) may find in their home. Unfortunately, it is not uncommon for homeowners to receive bad advice as to who to consult and how to remedy the problem. This can lead them to accept cosmetic repairs as a complete solution or expensive repairs that do not address the root cause, allowing the problem to recur in some form or worsen. Certain foundation problems are quite common: Continue reading “Five Common Residential Foundation Problems”
The use of manufactured wood products is ubiquitous in residential construction. Metal plate-connected wood trusses are among the most popular manufactured structural elements in homebuilding. These trusses replace conventional rafters and ceiling joists with considerably smaller-sized lumber connected by “web” elements typically made from 2x4s, using metal plate connectors. The top chords, which support the roof sheathing and the bottom chords which support the ceiling, resist gravity loads in compression and tension respectively as a large unit, rather than as individual beams. The result is a stronger and stiffer roof that is also lighter and can be quickly assembled with a crane.
Construction is a field with numerous specialties and specialists. As such, most construction projects require that the owner or developer assemble a team to ensure that people with the correct specialized knowledge and skill are available to complete the project. Most significant projects have two teams; one team designs the project while the other constructs it. Sometimes the lines between the design and construction teams blur, like when some portion of the design is delegated to the constructor.
For building projects, the design team is commonly assembled by the architect, while the construction team is assembled by the general contractor. Commonly, some, if not all, of the design team members are consultants to the architect. Architects know enough about the other disciplines like structural, mechanical and geotechnincal engineering, land surveying and interior design to be able to effectively engage those consultants and integrate their services into the overall design of the project. Similarly, general contractors have experience in subcontracting parts of the work that they do not self-perform and integrating the work of their subcontractors into the project.
As summer arrives, homeowners will seek to make the most of their outdoor space. While there are numerous ways to enjoy a backyard, decks and porches provide for a versatile, semi-permanent platform for outdoor activities that is less affected by weather and requires less ongoing maintenance than a lawn. During good weather, they can serve as additional rooms to the house. They connect the interior of the home with the outdoors, especially for parts of the home that are elevated above the surrounding ground.
Most residential decks and similarly constructed porches are wood structures consisting of simple lumber floor joists that are supported by the wall of the house and one or more lines of beam-and-pier supports. Guardrails usually surround the perimeter of the deck supported on stanchions, which are anchored to the deck framing. Wood deck construction is deceptively simple. The elements and relatively easy to assemble and their functions are intuitive. Consequently, a lot of homeowners see the construction of a wood deck as an ambitious but entirely feasible do-it-yourself project. Deck construction is bread-and-butter work for a lot of home improvement contractors. Continue reading “Should a Homeowner Design Their New Deck?”
Strong demand for real estate purchases and renovation of existing buildings has resulted in a lot of recent calls for structural or foundation condition assessments. These engagements vary in scope depending on the purpose and the conditions to be assessed, but they typically involve a site visit followed by the issue of a report. Sometimes they are intended to assist the buyer of a property with due diligence either in response to an issue raised by an inspector or as a stand-alone structural condition survey. Sometimes they are to aid a seller in responding to a buyer’s concerns. Sometimes the purpose is to evaluate the cause of distress and to develop remedial options. And sometimes they function as feasibility studies for additions and other major alterations. Whatever the motivation, a portion of the increase in condition assessment calls has come from inexperienced prospects, some of whom have wildly unrealistic expectations. On multiple occasions, either during the initial call or after receiving the proposal, I have heard prospective clients express their assumption that the assessment they requested would require “just an hour or two” of professional services.
This assumption is wrong, of course, and reflects a common misunderstanding about how structural engineers solve problems. Much of the public, as well too many architects, civil engineers and contractors believe that structural engineers design from memory, like the general contractor on your favorite home improvement program who always knows what is and is not “code”. They expect the structural engineer to be able to look at a structure and make a pronouncement as to its adequacy on the spot like the contractor on television. Some do not understand the purpose of structural engineers at all since contractors supposedly have the same knowledge, but they can build the building as well.
A quick internet search will turn up dozens of news stories about catastrophic failures of decks, balconies and similar structures at restaurants, apartment buildings and beach houses among other places. Many of these are mass-casualty events involving multiple injuries and occasional fatalities. It seems like there are several every summer. Failures of these outdoor accessory structures are indeed relatively common and are probably among the most common types of structural collapses. However, most deck, porch and balcony failures are not catastrophic enough or do not cause enough carnage to make the news. This would include most residential deck failures.
Like many businesses large and small, RJD Residential has made adjustments to its operations in response to the COVID-19 public health crisis. In the last few weeks, RJD Residential has made provisions to continue to serve the residential construction community in the current environment. However, emergency orders and the need for social distancing in everyday operations will affect some services for the immediate future, as described below. Continue reading “COVID-19 Update”
A common reason for a homeowner to need an engineer is to evaluate a foundation crack or other distress in a home. Sometimes this need can arise during pre-purchase due diligence at the recommendation of a home inspector. The experience of working with a home inspector may anchor a homebuyer’s or homeowner’s expectations about obtaining an engineering evaluation. It can come as quite a surprise that an engineering evaluation for a single issue could cost more than an inspection of a whole house by a home inspector. The home-buyer may also be confused as to why they need to pay to have someone else look at their prospective purchase. However, home inspections and engineering evaluations are two very different services. Continue reading “What’s the Difference Between a Home Inspection and an Engineering Evaluation”
If you live in a colder, four-season climate, it may look like the construction industry goes into hibernation as winter approaches. This is largely true for the types of public projects with which people interface in their daily lives, like road paving. However, building construction is a somewhat different story. While it is true that building construction slows down during colder months, a lot of construction activities can be performed over the winter and homeowners can use that to their advantage in planning their projects.