Assignment 4 comments

Assignment 4 went well. If trends continue from year to year, most of you will be, or already have, selected a structural concentration, and as such, this will be the majority of your experience with HVAC during your career.  
Hopefully you all have some familiarity with the various HVAC systems and their applications now, and can make basic analysis and design.  We were glad to see that most of you used EQuest in your analysis.  This can be great for general, quick calculations, but can also be highly customized to provide accurate analysis as well.

A couple things to note:

1.  When sizing members, keep in mind what sizes are available.  For example, you will not be able to find circular duct work 1.38675 feet in diameter.  When your analysis returns a required size, try to find the next readily available size up that will work.  This is not really pertinent to this project, but in the professional world, you will need to identify members that can actually be purchased.  This is true for all design, be it structural, HVAC, Architectural, Plumbing, ETC.

2. When designing HVAC systems, a combination of multiple systems is almost always used.  While selecting a main system is acceptable for this assignment, most buildings utilize as many as 4 or 5 different systems.

Overall, a good job, and good luck moving forward.

Thanks,

Brad & Steve

Storm Water Approaches

In class I outlined the main approaches to storm water management.  In the way I phrased things I may have been unclear, so I’m summarizing issues here.

Basic Requirement by Water Department

• The first inch of rain that falls on a site must be retained for at least 24 hours.

What This Means In Practice

• The portion of the site that is sufficiently pervious may be eliminated from calculations
• The designer must address only the portion that is impervious for calculation purposes
• The formula would be = Aimp * 1” / 12 = CF of water to address

The Primary Design Methods are

• Green roof
• essentially making that roof surface pervious for storm water purposes
• An overflow is provided for a large storm event
• Rain Garden (similar to Bio-Swale)
• Area with crushed rock below grade allowing water to be temporarily held in the voids. 
• An overflow is provided for a large storm event
• Detention Pond
• A depression in the earth that fills with water in a storm even and either drains off slowly over time and/or is absorbed into the earth
• An overflow is provided for a large storm event
• Cistern and Reuse
• A storage tank sufficient to hold the necessary volume.
• The retained water is used by a building for various purposes, often with treatment
• An overflow is provided for a large storm event

Senior Design Presentation Calendar

Here’s the link to the unofficial calendar of senior design presentations.  It’s best viewed in Week view.  You’ll see the full information by clicking on any entry.  Note that a few titles may have changed.

Assignment 3 Comments

Assignment 3 seemed to go fairly well for most of you, although many of you mentioned that it was a difficult assignment, particularly for those not in the structural concentration. I think that you all have the typical assignment comments down by now for the most part. Follow the rubric, fill out every section, make educated attempts, etc. I'm going to focus my comments here on some general structural things that many of you seem to have missed or struggled with.

-Many of you only showed beams spanning from column to column in your steel framing plans. In typical cases you also need beams spanning in between these beams. This is because a normal floor or roof system can only span 5-10 feet. If your columns are more than this distance apart, more beams are needed to support your slab.

-Typically structural engineers do not like things interfering with their structural members. This is because their calculations are based upon having the full capacity of the shape. Cutting out a section of a steel beam or column obviously decreases its capacity. So while it may be possible, it should be avoided unless absolutely necessary, as it will lead to complicated calculations and larger structural members. A good example of this would be not putting windows in a shear wall, as they disrupt the flow of the loads through the wall.

-Almost all of you modeled your building in SAP. This is completely fine, but a bit unusual to me. My (admittedly limited) experience has been that SAP is best used to analyze single beams and smaller structures in cases where you have complex loading or need very in depth analysis of what is happening in a smaller area. Programs like RAM Structural are more often used to model whole buildings and size members, columns, and foundations. SAP is fine, but those of you that are interested may want to explore other programs in the future.

Overall you all did well. If there are any questions or comments, let us know.

Best,
Steve and Brad

Assignment 2 Comments

Assignment 2 was an overall success.  Nailing down the architecture section quickly will be one of the most important things when you get to senior design.  Once we know for certain what the building will look like, we can begin the real design process. 

For the most part, the drawings provided were well done.  Many groups failed to include blow-ups of important areas, but most were clear enough without them.  It would be nice to have seen more numbers attached to the sizes and loads in some of the buildings, but the basics were provided.

Hopefully the fire protection work showed you that fire code can be hugely limiting in the design of a building.  Floor plans are often dictated as much by fire code as by anything else.  

Remember that as you go through each assignment, one of the most important things is the recommendations section.  Here is where you can go to see problems that previous groups may already have identified for you to consider, and where you can provide information on problems that future groups may encounter when they work on the project.

Thanks, and keep up the good work!

- Brad and Steve

A3 Presentation Information

For the wrap-up of the structural design we’ll have another presentation.  Here’s the relevant information to plan for your presentation.

• Length: 3 min
• To Cover
• Basic Structural System Choice
• How gravity and Lateral loads are carried to the ground
• Changes from Architecture
• Advice to HVAC Engineers
• Voting for 1-point extra credit
• Here’s the link for individual voting after the presentations

Partial Checklist for Architectural Design

Here are some issues to check for your design.

• Site

  • How do vehicles access the site – and exit from it?

    • Employees

    • Visitors

    • Service vehicles

    • Emergency vehicles

  • How important is pedestrian access?

    • Where do they come from and go to?  Make assumptions if necessary.

  • Is it important for your building to be visible from the roads?  If so:

    • What aspect of the building should be emphasized?

    • Does this mean the building should be right at the corner or somewhere else on the site?

• Building Plans

  • Circulation

    • Where is the main employee entrance?

    • Where is the main service entrance?

    • Should the visitor entrance be separate?

    • Does every occupant have two separate protected exit paths to the exterior within 50’ (if building is sprinkled) of leaving their room/suite?

    • Is there a need for a passenger and/or freight elevator?

  • Adjacency

    • Are the rooms/spaces of the building that need to be together in fact together

      • Check what the building program said about this.

  • Views

    • Are there exterior views from the building that you should be taking advantage of?

  • Energy Use

    • Is the form or orientation of your building going to make it particularly costly or economical to occupy.

      • e.g. In northern climates taking advantage of solar energy for heating often means relatively “skinny” buildings with their long axis east-west to capture sun for both heating and daylighting.

  • Space Provision

    • Have you checked the sizes of the spaces against what the program required?

      • If there are differences can you explain why you made the changes?

• Building Elevations

  • Are your elevations important for aesthetic impact?

    • if so, what are their characteristics that address that impact?

  • Are those elevations (and potentially roof skylights) going to help or hinder the building’s energy use?

    • Related to this is the question of what are the materials of which the exterior envelope is made?

• Provision for Engineering Systems

  • What’s the longest span in your building?

    • Have you allowed enough depth for that span and HVAC and electrical systems?

  • Will it be possible to address lateral loads with your design?

  • Are their provisions for HVAC and plumbing equipment?

    • Space in the floor plan that allows good duct runs, outside air and exhaust air, equipment servicing

    • Is their sufficient space above the ceiling (or below the floor) for HVAC duct runs?

      • These issues are often best considered via building sections.

    • Are there vertical shafts sufficient for HVAC ducts (supply and return)

• Acoustic Issues

  • Have you separated noisy spaces (e.g. mechanical rooms) from quiet spaces?

  • Are there any special acoustic requirements that might affect the floor plan