I work for a small engineering firm in coastal South Carolina (high wind 110mph-130mph and seismic zone D0-D2 zones).We do primarily wood-frame residential work. Over the past few years, I have become a frustrated with the state of engineering particularly as it applies to residential engineering. I believe that most of the engineers on this mailing list are in
To give you an idea of what I am accustomed to in our practice:
- Contractor/Homeowner brings in a set of architectural plans
- Depending on the complexity of the structure, we may or may not require framing plans from the truss manuf.
- Option 1: Contractor provides truss framing plans: This usually takes a few weeks, because no one plans ahead of time and when they bring us the plans they want the structural drawings as quickly as possible. We have also had the case where a truss manuf provides a set of truss calcs and a layout for quote purposes and we do our design by that only to find out that the customer purchased trusses from a separate manuf, who used a different configuration.
- Option 2: We provide truss framing plans or “stick” framing plans. This option is good because we have flexibility in our overall design, but the coordination is not carried thru. With truss framing plans, it is left up to the customer to communicate to the truss designer the need to adhere to our layouts. I don’t think this is done too often, because it is pretty common to give out the architectural drawings to the engineer, component suppliers, subs all at one time. If it is “stick” framed, we have found that whether or not the customer follows the framing plan, the residential inspectors are not equipped to review it in the field.
- Whether we have truss designs provided or come up with framing plans, we generally “fully engineer” the structure according to the IBC (another discussion for another day is whether this is an accurate description, to me it is really a hybrid prescriptive/engineered design). Our drawings usually include a foundation plan with shearwall holddown sizes and locations, framing plans with any notes pertinent to gravity loads or lateral loads, and a sheet of standard details modified slightly for each job. (Ocassionaly we will include building sections if needed)
- The plans are usually provided to the customer (this is the only other “meeting” other than the initial plan “drop off”) and if there is anything really out the ordinary (Simpson steel shear wall, APA portal frame detail…) we try to flag it to the customer. The customer is responsible for coordinating any products and components that are needed or may be unique to his design.
- Customer then submits plans to building department along with architectural drawings and plat for a permit. Then the standard inspections apply for the different phases of construction. We have never done any special inspections and we typically do designs for anywhere from a one story 1200sf slab on grade residence to a 5000sf 2-story residence on piles.
The local jurisdiction where most of our work is located requires the following: “plans drawn to scale with wind and seismic design per 2003 IRC (with original SC engineer or architect seal)”. Point being the building department is not very concerned with the engineer being a part of the design team as in commercial work, but rather they are simply facilitating the idea that engineers simply “stamp” plans for a couple hundred bucks. Anyway that is also another discussion for another day. Today, I am just looking for the process that most of you engineers go thru for residential engineering/coordination in your area. Thanks.