The PE-Services Design Exchange

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LEED, Green, and Sustainability

2009-02-23T12:05:00.004-05:00

A few words you might have heard a lot lately?!? Seems like I have been asked about them on an ever increasing basis. What are they all about? Are they the same thing? What do they have in common? These inquires have forced me to dig into these issues and have helped me to grasp what these words really boil down to, and it’s not what most people would initially think.

Let me try to get at this from a different way. This may be hard to believe, but I loved math as a kid; I am an engineer through and through. Anyway, one of the math subject matters I recall was a section on sets and subsets. If you don’t remember the math terminology let me state it in layman’s terms - If all engineers are geeks does that mean all geeks are engineers? The simple answer is “no” (as a matter of fact we are not even all geeks) and the same applies to the LEED/Green argument. I trust that this will become clearer through the examples and discussion provided in the next few moments.

The LEED (Leadership in Energy and Environmental Design) process is a voluntary rating system for earning green credits in six different fields: sustainable site development, water savings, energy efficiency, materials and resources selection, indoor environmental quality and innovation & design process. It involves a score card system, a formal application and an approval process to certify a construction project as LEED Certified (Just as a brief aside – the USGBC is to be releasing a LEED for Retail in 2009 after Beta testing throughout 2008). While this is a definable way to document that your project is certified green and that your project utilizes sustainable design features, it certainly is not the only way to go green. In light of the set/subset discussion above, I like to summarize like this – All LEED projects are considered green but you certainly can have a green project without being LEED certified.

So why use the LEED process? What are the advantages? Well, the fundamental advantage to LEED is that it offers a formal stamp of approval to say, “Our project is environmentally friendly.” Another important plus about LEED is that it has allowed for a quantifiable way to define sustainable design - LEED is an established and accepted measure, which has shed light on the importance of environmentally conscious design. The hang-up that I (and many others) have with the LEED process is the impact it has on the time and financial resources of a project. While many claims are being made that the upfront cost of LEED is offset by long-term gain, I am a believer that LEED has been slowly adopted within retail construction because retailers and developers alike have to get maximum benefit from their upfront dollars. This places many designers between a rock and a hard place, desiring to be environmentally friendly while also offering the client the most bang for their capital buck. In a market where many retailers have strict construction and operating budgets, it seems to grow even more difficult to go with LEED. Until both of those sides can be reconciled with a solution that is viewed beneficial by both, LEED certifiable green designs will be difficult to make. Simply stated, I believe that there are rarely solutions that are cheaper upfront and cheaper in the long run. Either you pick the cheaper solution (incandescent track for example) and you pay the piper later through higher electric bills or you choose the higher cost options (in this case maybe LED or ceramic metal halide track heads) and you save on your long term energy bills. So what’s a retailer or developer to do?

I would argue that while there are many components within the LEED process that are energy efficient, you do not have to decide to have a LEED certified building to make sustainable decisions that allow you to have a “greener” facility. As a matter of fact, I recently decided to do an informal survey on my own regarding the general understanding of green, sustainability, and LEED. While I’ll admit, as an engineer I would like a lot more scientific evidence for my argument, this brief study enforced what I had formerly believed. Outside of our industry (design and construction), very few people really understand sustainability and even less had heard of LEED. It seems to me that if this is the case, having a LEED certified project is not a prerequisite for customers to view you as green. I just read about a retailer who is displaying signs throughout their store pointing out areas where they are utilizing green technology and green construction methods. It appears that the average consumer is quickly becoming aware of what it means to be green and environmentally friendly. Recent trends show consumers are factoring sustainability into their decisions of where to shop and what to buy. All that being said, I believe there are ways to save long-term dollars and be environmentally friendly in order to appeal to your customer base. Below I have provided just a few of the many ideas which you could implement to save energy and gain the confidence of you customers.

Lighting is a critical component of most retail design, so as we review new lighting technologies it is crucial that we not only save energy but that we maintain the color rendering necessary. The following are just a few examples of the latest technology - new fluorescent compact and T5 lamps, ceramic metal halide, new LED track fixtures and I am sure more is on the way. As an example, we have a grocery client who is currently making the change to LED track lights for many areas throughout the store and they are also installing skylights and daylight harvesting controls to maximize the use of sunlight within their store to reduce their energy usage during the peak demand hours. All of these current technologies have nice applications within retail design as long as they are utilized in the correct locations and the retailer can budget for the additional upfront cost. As I mentioned earlier, these added costs can be more than offset by long-term energy savings, especially when the installation is in a new application.

Another large expense for most retailers is their HVAC systems. We typically recommend that retailers look at two key areas in order to increase the sustainability of their HVAC systems – unit efficiencies and controls. As I noted earlier, a retailer or developer must be willing to spend additional capital upfront in order to design systems with long-term savings in energy. Whether utilizing an applied system (ie – VAV, Water Source Heat-pumps, etc) or more efficient package units, the design of higher end systems will always lead to lower operating costs, and in many parts of the country, a quicker return on the additional investments. The other area which also provides for a reduction in long range energy costs is HVAC System controls. Many of the systems installed today can be viewed by a corporate system that can allow for load reduction at peak times, as well as ensuring systems are not left in a full load position during off hours. Another side benefit of these control systems is that they can be monitored for maintenance issues as well, which can often lead to additional reduction in maintenance cost and store down-time.

The final mechanical system design which should be monitored for a sustainable design is the plumbing fixtures. Whether utilizing low flow plumbing fixtures (in some cases no-flow fixtures with waterless urinals) and insta-hot water heaters, there are opportunities for green designs and in the case of LEED a nice opportunity to gain some design points. So while many of the plumbing options might not save significant dollars for most retailers, there are many design features that will not break the bank. Plus these design features provide retailers and developers yet another opportunity to promote greener facilities to an ever more watchful consumer.

The LEED process is a good thing, but a project does not have to be LEED certified to be green. The goals of LEED are to further the sustainable movement and encourage a shift in the focus of designers. However, if your project cannot afford to seek certification remember LEED is only a subset of Green and don’t let that keep you from doing what is best for you, your community, and your customers. Bottom line – we should all make green choices that are better for the environment and the future and we all win.

Plumbing & Fire Protection - Post 3 of 3

2008-07-10T14:15:00.001-04:00

Flexible Retail Center Design - Plumbing & Fire Protection –

The design for plumbing in a retail shell building is typically straight forward; however there are several considerations which should be reviewed when designing the water, sanitary, fire protection and gas (where applicable) systems for the overall center.

Water - When considering domestic water service, it is important to bear in mind the type of tenants that will be served. Depending on the local pressure and water flow, a typical restaurant space could require a 2” line as opposed to a retail space which might only require a ¾” line as long as tank type toilets are utilized. The most flexible design involves working with the developer to consider a worst case scenario as far as water usage is concerned. This worst case can be utilized to size the overhead pipe size that can be run with a series of 1” and 2” taps/valves to allow for ease of future tenant connections. Typically as a cost saving measure, deduct meters are installed under the tenant installation, as all of the valves may not be utilized.

Sanitary - Sanitary waste systems for most retail facilities are very basic with a 4-inch building sanitary main being typically sufficient. There are three basic options for sanitary design. The first is to run under-slab the entire length of the facility with the sanitary main providing cleanouts only at code required locations. This pipe can be run in either a 10ft “leave-out” (no concrete slab) in the rear of the space or it can have the slab poured completely over it. While this approach has an initial low cost, it is often more than offset by slab cut/patch and longer tenant construction timeframes.

A second approach to sanitary, if the landlord has a good idea of the types of tenants they will be attracting, is to run the entire length with the main sanitary and providing restroom stubs in a few key locations for possible tenants who need to get in their space quickly.

Once again, food service facilities will have additional requirements - specifically, the need for a grease interceptor and related grease-laden waste piping. Unless a specific tenant is known, grease interceptors are not typically designed under the shell package. While there are many ways to handle the grease waste, the most flexible approach if a space has the potential to be a restaurant is to provide two stubs out of the facility in case the grease interceptor must be located outside of the space.
Fire Protection - Typically under the shell design a main riser will be installed and in some cases a line will be installed along the entire rear of the facility. The logical question is how big should the line be (both the incoming and the overhead). More than any other aspect of the design, this is dependent upon the available flow and pressure from the local utility. Once the information is acquired from the utility, the sizing of both the main entry and the main riser size can be calculated based on the size of the spaces and there intended use, or worst case usage if tenants are unknown.
Gas – When gas is available at a site there are two primary design decisions that must be made with regards to gas service for a retail shell building. The first is the overall requirements of the facility and the second is distribution of gas piping. As noted with water service above, based on the worst case anticipated needs of the developer, the main gas service can be sized. Ensuring that enough gas is brought to the site is critical as acquiring additional gas after pavement is down can be extremely expensive. The distribution of gas piping is dependent upon the selections made during the HVAC design phase. If gas is needed in the shell space, there are two options for gas piping. The gas pipe and associated metering can either be all sized for retail tenants, all for restaurant tenants, or a combination based on the developers expectations for each space.

As you can see, one set of design parameters will not fit the plumbing requirements of all retail centers; however, a little planning ahead can increase the facility flexibility for both the developer and the future tenants.

Flexibility? So flexibility is dependent upon your perspective. One extreme is no utilities provided, which is a low upfront cost approach at the sacrifice of tenant build-out timing and possible damage to the integrity of your building. While the other extreme provides utilities as if spaces were almost ready to occupy – this approach costs more upfront and limits flexibility but it does speed up tenant occupancy. The conclusion being there is no “one size fits every retail center” solution; however, a careful analysis of each of these components will lead to the most flexibility for your next center.

Trent Beighle, PE is the president of PE-Services. For further information contact Trent at trent@pe-services.com or Roger Butler, PE at roger@pe-services.com.

Flexible Retail Design - Electric - Post 2 of 3

2008-07-10T14:10:00.001-04:00

Flexible Retail Center Design - Electrical Systems–

There are two main considerations to review when beginning the electrical portion of a retail shell design. The primary consideration is the Electrical Service design for the entire facility as well as the individual future tenants. While there are many lighting decisions to make which are primarily preference driven (parking lot lighting, accent lighting, etc.), the emergency/egress lighting is a code consideration which must be evaluated throughout the shell design phase.

In order to create as much flexibility as possible, the main service design will vary widely based on the building size. For larger centers, this may be accomplished through a package switchgear unit or for a variety of centers it might include a wireway with a series of disconnects and meters. As noted with other utilities, the main focus of this portion of the design should analyze the worst case usage. The equipment size is not always reflective of the worst case, but in order to maximize flexibility the secondary conduits from the transformer should always be provided based on the best analysis of the load for the entire facility. The primary difference is that while the package switchgear cost considerably more, in larger applications the space requirements can be significantly less than the wireway option.

Once the main service is designed, consideration must be given to conduit, wire, and panel distribution for the future tenant spaces. Should panels be installed in each space or should we just install conduits. If we decide to install conduit only, what size should we install. The answers to the questions will be based on the confidence the developer has in their knowledge of the future tenant types as well as the necessity to get tenants in the center quickly.

The least flexible tenant service design, although the quickest for future tenants, is to size the panels based on the intended use of the space and provide the meter, disconnect, and panel under the shell package. There are two other approaches which involve empty conduits for future spaces – these conduits can be run under the slab or to maximize flexibility they can be run overhead so as to allow conduits to easily be shortened or extended as tenants require. While not as flexible as the overhead conduits, the conduits underslab can be increased in size to add flexibility while not adding the same costs to the project as overhead metal conduit will. These same alternatives need to be considered for telephone/data conduits to each tenant.

Flexible Retail Shell Design - Post 1 of 3

2008-03-07T15:04:00.003-05:00

PE-Services has written an article for a recent issue of Retail Construction magazine (www.retailconstructionmag.com). Over the next month, there will be three posts covering flexibility in Retail MEP Design. Please post a comment or e-mail us if you have any additional questions.

So you want Flexible Lease Space?

One of the primary goals for the MEP design of each retail center, whether a large Life Style Center or a smaller rural strip center, is to have flexible lease space. The question always arises, “What if a restaurant wants this space?” or “What if a tenant takes three spaces?” While there is not a one size fits all solution for every center, there is a series of decisions each developer needs to make prior to beginning the mechanical systems design phase of a new center. Following is a description of various options for Mechanical, Electrical, and Plumbing/Fire Protection along with the pros and cons of each to assist with the planning phase of future retail centers.

HVAC – Since most locations use a model energy code which dictates the amount of lighting that can be utilized in a retail space and ASHRAE 62.1 is widely accepted as the standard for calculating the amount of outside air required for a space, sizing and installing units for a typical retail space under the shell package is not a huge risk. The advantages of doing this include having all the equipment from the same manufacturer and a shorter tenant fit up time. The drawbacks to this approach include the upfront cost of the units before tenants are in place as well as the potential that some other type of occupancy, a restaurant for example, really wants a particular space - thus the need to view design with a balance of cost and flexibility. Below is a brief explanation of the various types of systems which can be utilized in retail design along with the flexibility pros and cons of each.

Roof Top Units (RTU’s) - By far, most owners will opt for the use of package roof top units. These units combine heating and air conditioning into one unit, either electric heat and cooling or gas heat and electric cooling, and typically require a flat roof for mounting. These units can be designed based on the intended use of each space, or if not known at the time, loads can be calculated based on typical retail usage. When utilizing RTU’s there are three options for the shell package: install the units based on typical retail requirements, install curbs only based on intended usage, or install no units under the shell package.

If the developer decides to install the units under the base shell package, placement of the unit can increase flexibility. As long as there are no visibility issues, the units should be set to the front half of the building. This will allow flexibility if the space is leased to a restaurant as the additional units could be placed on the rear of the space where a kitchen would typically be located. This type of application is not only very flexible but increases the speed of future tenant build-outs.

The second option is to place the roof curbs in anticipation of future RTU placement. Since most manufacturers’ equipment utilizes the same roof curb for groups of unit sizes, this leaves the sizing of the equipment fairly flexible. One major cost implication is being locked into a single manufacturer (to match the curb), which will likely increase the cost based on a sole source manufacturer. The advantages of this approach is that the units are not purchased until tenants are identified while allowing the roof work to be done under the base building to ensure a good continuous roofing system by one contractor.

The final option is to put no curbs or units in under the shell. While the advantages are no cost upfront and maximum flexibility for unit placement as tenants are identified, the major disadvantage of this approach is cutting holes in a new roof each time a new tenant moves in.

Split Systems – If there is no provision made for roof mounted equipment, the design will likely require the use of air cooled split systems. These systems require a furnace inside and an air cooled condensing unit located outside the building. While this system is less costly than a RTU it has even more limitation, such as a maximum of 25% (or less) outside air and the typical requirement for inside floor space. Based on these limitations this type of system is typically only utilized in very small spaces.

Central Systems - Strictly from an efficiency and flexibility standpoint, the most flexible HVAC system for large retail and mixed-use applications is a central system consisting of either a chiller/boiler with associated water piping or large RTU’s with main duct runs. These units provide a lot of flexibility; however, the initial cost of this type of system and the requirement for the landlord to prorate energy bills will keep the vast majority of malls, strip centers and stand alone buildings from using this type of system.

Temporary Heat – Most locations, other than those in southern states, require some temporary heat. If units were actually installed on the roof under the shell package, one or more of these units could be utilized as temporary heat. Another option is to provide unit heaters, either gas or electric, and connect them to a “house service” – these units can be relocated as required as tenants occupy spaces.

While there are various options for heating and cooling retail facilities, a close review of each project will help filter the choices. The primary points of analysis should include the size of the development, utilities available, how long the developer plans to hold the property, and last but not least, the anticipated tenant mix.

About PE-Services

2008-01-04T13:30:00.002-05:00

PE-Services is a fast-paced MEP engineering firm that knows retail and hospitality design inside and out. Our firm has provided HVAC, plumbing, and electrical engineering for malls, hotels, restaurants, and stores across the United States. PE-Services’ clients appreciate our unique blend of old-fashioned service and attention to quality, along with 21st-century speed and technology. We have registered engineers and support staff ready to serve our clients quickly throughout the United States.

To learn more about PE-Services and how we can help you, visit www.PE-Services.com