In the past, I have written a few posts that bring up the topic of design review including:
- Equipment Replacement Cost Calculations; There’s More to it than Simple Payback
- Design Review; Leveraging Opportunities Before Ideas Become Realities
- Design Review – Same Frame Size, Different Fan Sizes – Part 2
- Design Review – Taking a Look at Coil Options
Its not unusual for people to ask me if I can suggest design review resources and that happened just the other day at dinner. So, I thought I would just make a blog post that shared what I know in answer to the request.
Incidentally, some of the posts above were from when the blog first stated on the CSE web site. When the magazine shut down for a while and I decided to continue the blog on my own and moved it to this venue, many of the older posts were corrupted when I made the transfer; the text came through but the formatting was bad and the images were lost. I have been gradually working my way through the older posts and fixing that and some of the posts linked above fell into that category. Thus, I have taken this opportunity to make repairs on them and they should be much more presentable now.
- If you had looked at those posts in the past and wished the graphics were there, they are now so you may want to revisit them, and
- If you ever run into an older post that his messed up and would like to have a cleaner version, just let me know and I will shift it up the list and try to restore it sooner rather than later.
These links will jump you to the various topics in this post. Each section should have a “Back to Contents” link at the end that should bring you back here (assuming I go the code right).
- Functional Testing Guide Checklist Tool
- Design Review Tool Module Master Reference Guide
- Office of Energy Publications
- Design Briefs
- Design Guides
Functional Testing Guide Checklist Tool
The Functional Testing Checklist Tool and Test Directory is a tool that you can use on-line or download to your hard drive and use when an internet connection is not available.
When you open the tool you will be provided with a number of checklist selections including air handling systems, boilers, chillers, etc. If you select one of the topics, you get a checklist highlighting important checklist requirements associated with the topic.
If you click on the icons associated with each checklist item, you will be linked into the content of the functional test guide that pertains to that particular issue.
Some of you may be wondering what functional testing has to do with design review. In my experience, which I believe might be mirrored in the experience of others in the commissioning field, most commissioning issues are unresolved design issues. That means that if the checklist tool has identified something as being important to test for, then its probably also something that should be addressed by the design documents. Thus it is something that you should be looking for during your design review.
For me in particular, if I uncover something in a design review process or construction observation process that I am concerned about, it is quite likely that I will test for it. If nothing else, the test will satisfy my curiosity about the issue. And, for my client, it will ensure that any potential issues have been addressed by the test plan if they were not resolved via the design review or construction observation process.
Design Review Tool Module Master Reference Guide
This document is part of the supporting infrastructure for the Commissioning Assistant tool on the Energy Design Resources web site. The tool is simply a list of things to check for during your design review process, covering the topics indicated in the screen shot from the table of contents below.
The tool is coded to indicate if each item should be reviewed during the design development phase, the construction document phase, or the shop drawing phase, as illustrated by this screen shot.
The list was developed by interviewing experienced commissioning providers and then compiling the results, including a peer review process.
Office of Energy Publications
The office of energy provides a number of resources that are useful in the context of design review.
The content is grouped into the following categories.
Each category has resources including tip sheets, software tools, and source books (reference books) on the topic, all of which can be downloaded at no cost.
The relationship to design review is that the opportunities discussed are good design details to consider looking for in your review process, especially if you are looking for things that will save energy and other resources. In addition, may of the resources include useful metrics that will help you project the cost/benefit relationship for something if you propose including it.
Of course, the information on this site is also a great resource if you are out doing retrocommissioning work.
The Energy Design Resources web site provides a large, ever expanding selection of design briefs on a wide range of design topics. So, it is a good resource to check when design issues come up.
Having said that, there are a number of design briefs that come to mind when I thought about the topic of design review. The first three I mention actually started out as a single document called “Design Review”. But the first draft revealed that in terms of length, the document was not, for lack of a better term “brief”. So, it was broken up into three documents; Design Details, Design Review, and Field Review.
This brief looks at how the details of a design can have a significant impact on its efficiency, operability and first cost, including examples of items that reduce cost while providing operational and efficiency benefits.
I should note that just about all of the other EDR Design Briefs contain similar information regarding the details of the design issue they target. For instance, the brief titled Centrifugal Pump Application and Optimization devotes a significant amount of its content to pump selection and specification.
The Design Review brief is, obviously, targeted at design review. It includes a number of techniques that can be used to evaluate cross-check the design intent of a project against the actual documents that comes out of the design phase and submittal phase of a project; the documents that will be used to turn the dream into a reality.
One of the topics explored by the brief is the cost impact of a seemingly minor change in the pumping head requirement associated with an equipment substitution. While the actual change in pump head is minor and with-in the safety margin of the pumps selected for the design, the accumulated impact over the life of the equipment is fairly significant, as documented by a table in the brief, which is reproduced below.
The Field Review brief is targeted at insuring that the good intentions of the design review process are made manifest in the field. Design documents typically are trying to convey what is required by a three dimensional reality via two dimensional paperwork and there is often room for interpretation out in the field as systems are installed. If the intent of a design is misinterpreted, the final result will not meet expectations, no matter how good those expectations were.
For example, a single point sensor installed to measure the mixed air temperature probably is not going to do the job intended, as illustrated in this figure from the brief.
(To gain some insight into the stratification issue that is brought up in the brief and why it matters, take a look at the field test data in my previous blog post titled Retrocommissioning Findings: Economizer Mixed Air Plenum Stratification–Overview.)
Improving Mechanical System Energy Efficiency Through Architect And Engineer Coordination
In addition to being a contender for the coveted prize for longest design brief title, this brief explores techniques that can be used early on in the design phase to improve the efficiency of the systems and equipment by coordinating architectural elements with the requirements of the mechanical design.
For example, a technique is illustrated that can be used to estimate fan static pressure requirements during the design phase, a skill that allows the mechanical designer to coordinate with the electrical designer during the early phases of a project to provide accurate assessments of the electrical distribution system requirements.
Such an assessment, which is based on project specific details rather than a general assessment from the last project, provides a much firmer foundation for initial equipment selections, mechanical space requirements, electrical distribution system requirements, etc. and can be readily defended because of its project specific foundation when challenged.
For a commissioning provider, developing this skill allows you to quickly cross-check a fan static or pump head specification if your gut makes you doubt what you are seeing. I use this technique during design review, but also in the field when I think I may have found a pump that is oversized. I wrote about applying it in several different articles, including Right Sizing Pumps.
Design guides are a step up from a design brief; page count is no longer an issue. I believe all of the design guides I will discuss grew out of PIER research (the California Energy Commission’s Public Interest Energy Research Program) that showed that significant energy savings could be achieved simply by applying best practice to design processes.
To me, this was both an encouraging and a discouraging result. It was encouraging because it said there were no real hurdles to achieving savings in the 5-10% range; all we had to do was apply the best knowledge we had to the problem. But it was discouraging for that very same reason; specifically, why are we not already doing that?
In any case, a few of the guides that I reference include the following.
Cool Tools is a design guide that is focused on central chilled water plant design. It consists of nearly 300 pages of detailed chilled water plant design information, complemented by a number of tools like the Pipe Size Optimization tool illustrated below.
Advanced VAV Design Guide
The Advanced VAV Design Guide is basically Cool Tools for VAV air handling systems. These screen shots of the table of contents will give you a feel for the depth and breadth of its content.
Small HVAC System Design Guide
Of course, not every project features the central plants and large air handling systems that are targeted by Cool Tools and the Advanced VAV Design Guide. That’s where the Small HVAC System Design Guide can come in handy. This guide focuses on smaller systems; 10- tons of cooling or less, covering important topics like Integrated Design, Unit Sizing and Selection, Distribution Systems, Ventilation, Controls, Commissioning, and Operations and Maintenance for these systems. Since systems of this type could easily account for half of the systems serving new construction floor space, at least in California, where the guide originated, the opportunities are significant.
In many ways, the guide focuses on “right sizing” of the equipment because of the benefits that will yield in other areas besides efficiency, including first costs and maintenance costs. This concept is applicable to larger systems too, as is some of the data in the guide like this equipment load table for computers and monitors.
Advanced Lighting Design Guide
HVAC systems are not the only things that use energy in our buildings. Lighting systems are also significant users and lighting and day lighting control strategies are frequent commissioning targets.
The Advanced Lighting Design Guide started life as a document but has evolved to a website full of resources on the topic.
The link above takes you to the current web site location. But I have also placed a copy of one of the earlier versions of the guide on my Google Drive for your reference. While technology in this area is always advancing, the principles behind it are still the same. In addition, if you do retrocommissioning, you may need to deal with the older technologies vs. installing the newer ones.
Design review is a topic for a number of classes I do. In fact, there is one class we do on occasion at the Pacific Energy Center where it is the total focus for the day. The classes typically include case study examples that show how the concepts can be applied along with the specific benefits achieved.
So, I thought it might be helpful if I made some of the presentations I have available for your use. They are posted on my Google Drive and the links below will take you directly there. You an also access them along with other class content via the links on the right side of the blog under topic 03 – Materials from Classes and Presentations.
Design Review Class
These slides are from a full day class we do at the Pacific Energy Center on the topic. They include modules on:
- How and when to target the review cycle in a typical construction process,
- Design review targets in the Schematic Design phase,
- Design review targets in the Design Development and Construction Document phase,
- Design Review targets during the shop drawing review phase,
- Construction observation targets; construction observation is really just a design review process performed when things are starting to get real and will become much harder to change, and
- Commissioning targets; in some ways, commissioning is a “trail by fire” design review process.
Commissioning Findings from Design Review and Construction Observation
This is a presentation I did at NCBC 2005 and the subtitle is “… Sometimes, the Magic Works and Sometimes It Does Not”, which comes from the movie “Little Big Man”. Basically, it uses a case study format to look at why commissioning (the “magic”) sometimes works and sometimes doesn’t work. Many of the examples come back to design review items that were not addressed some how, thus my reason for including it.
It may also be one of my better conference presentations. Jay (Santos, one of our founding principles) often mentions it with a smile and tells me I should do it again sometime; who knows, maybe I will if the opportunity presents itself.
Design Phase Commissioning and the Rest of Life
This was a presentation I did at NCBC 2008 with a subtitle of The Impact of Design Phase Issues on Construction and On-going Operation and Maintenance. As the title suggests, it looks at the long term impacts of addressing critical issues during the design phase and the benefits gained by doing so.
A Mechanical Engineer’s Perspective on Electrical System Commissioning
This presentation is from NCBC 2009 and is subtitled Experiences and Insights Regarding Power System Integrity and Recovering from Power Failures. It could have just as easily been subtitled How We Shoved the Discharge Section of a 40,000 cfm Clean Room Make Up Air Handling Unit Six Inches Down the Steel One Memorable Day”. As is the case with several of the other presentations, the focus is not exactly design review. But many of the issues that are discussed are the results of missing something during design review or the related submittal review, construction observation, or functional testing process.
Optimizing Equipment Requirements
These slides are extracted from a larger presentation I do in a class for Marriott facilities engineers. They are the classroom version of the last three bog posts referenced at the beginning of this post.
Design review has been identified as a persistence enabler in a number of research efforts including one funded by PIER titled Strategies for Improving Persistence of Commissioning Benefits. This presentation looks at the various persistence strategies identified by the report, including design review, starting at slide 19.
Specifically, the presentation explores the impact of switching from plenum fans to SWSI fans for a semi-custom air handling unit, one that is typical of many on the particular project where this particular observation evolved. It includes a 3D model that compares the as designed and as proposed equipment configurations and the cost benefit analysis results, including the ripple effects.
Senior Engineer – Facility Dynamics Engineering