Rising Water; Increased Seepage
Lake Michigan is reaching near record high water levels in 2020 and is regularly featured on local news due to related challenges of rising water levels. The reality for buildings located near Lake Michigan is an elevated water table resulting in increased amounts of water infiltration, also known as seepage, into underground spaces that are situated at or below the water table. Water seepage can occur through foundation walls and slabs on grade via cracks or holes that have formed over time and, in particular, at cold concrete joints where two or more concrete pours meet each other. Increased water seepage can result in problematic additional moisture within buildings and pooling of water in building interiors.
Underground spaces located below the water table experience water pressure on the back side of the concrete slab. When the water table is elevated, increased water levels and associated pressure will result in increased seepage where seepage previously existed as well as introduce seepage in weakened areas where seepage was previously not occurring.
To counteract the increased water seepage, a de-watering approach should be developed and implemented to minimize water infiltration and impact to the building. Common de-watering measures include the installation of a pumping system dedicated to removing water from the backside of the building foundations, drain tile to collect water to be pumped away from the building, vacuum pumps, injecting cracks and holes, sealing concrete slabs, etc. Pumping solutions typically include a back-up power source to ensure the system remains operational during a loss of power. A combination of these and other measures may be required to combat seepage depending on a specific building’s conditions. In many cases, an initial investigative trial may be necessary to gather data before implementing a permanent de-watering solution.
Elara Engineering has designed de-watering systems applicable to below-grade spaces in existing buildings, including historic buildings, experiencing water seepage. We recommend, as a first step, an initial study to develop a de-watering solution that is applicable to a specific building and site which may include input from a structural engineer and experienced contractors as well as the building owner. A thorough understanding of the building’s specific conditions and requirements in addition to a well thought out design is vital to ensure maximum effectiveness of the de-watering measure(s) implemented.
For more information, please contact us at 708-236-0300 or email@example.com.
In light of the current COVID-19 pandemic, building owners and managers have increased their interest in HVAC strategies and products aimed at reducing the airborne transmission of viruses. While current research is limited on the specific characteristics of SARS-CoV-2 and its transmission, there is sufficient research on methods to help control the transmission of other infectious diseases.
For example, there are several strategies and products in the market today that are intended to reduce or remove pathogens from breathable air within buildings or systems. Many of these are supported by extensive research and practical experience while others employ new technologies with less substantiated data. Common strategies and products used today include:
- Increasing ventilation (outdoor air) rates
- Increasing air filtration effectiveness (MERV-13 or better)
- Installing ultraviolet (UV-C) lights
- In central air handling equipment
- At upper room fixtures in the space
- Implementing Bi-Polar ionization
- Installing local exhaust and/or ventilation supply
- Adding local filtration
These strategies can be implemented in new equipment/facilities or they can be retrofit in existing equipment/facilities. Strategies may also be combined to amplify their effect or to address varying needs. The right solution for your facility will depend on many factors and there is currently no one-size-fits-all solution. A comprehensive plan should be developed that is suited for a building’s specific goals at individual space levels.
The implementation of HVAC strategies aimed at reducing the airborne transmission of viruses within buildings should incorporate the following steps:
- Review Options: Working collaboratively with a professional engineer or industrial hygienist; identify, evaluate, and document potential virus mitigation strategies specific to the facility and its goals. These may include permanent or temporary measures which can be deployed now or in the future and may be part of a building re-opening plan under the current pandemic.
- Implement: Once options have been assembled and specific strategies selected, the professional engineer or industrial hygienist should prepare detailed specifications, assist in obtaining contractor pricing and review implementation by the successful contractor.
- Monitor and Adjust: It is important that after the implementation of any strategy, its resulting effectiveness and ongoing performance be monitored. This may include periodic testing of particulates or continuous monitoring through the building automation system and can vary widely based on the goals and strategies identified. Where actual performance is found to fall short of the desired thresholds, additional strategies can be implemented or controls adjusted to enhance performance. This monitoring and adjustment phase should be discussed and planned for as part of the initial options review.
Additional information regarding this topic is available through a recently released position document prepared by the American Society of Heating, Refrigeration, and Air-conditioning Engineering (ASHRAE) which provides an overview of infectious disease transmission and previous ASHRAE research. The document can be found here.
For more information, please contact us at 708-236-0300 or firstname.lastname@example.org.
Elara Engineering Associate Principal Matt Swanson, LEED AP, CEM and Associate Principal Caitlin Levitsky, LEED AP BD+C recently co-authored the above titled article placed as a featured story in the Spring 2020 issue of Chicagoland Buildings & Environments.
The heart of any building is its major mechanical, electrical, and plumbing (MEP) systems that allow the building to successfully operate and provide comfort to its occupants. However, when one or more MEP systems require repair or replacement, significant cost and inconvenience to building owners and occupants can occur. Mr. Swanson’s and Ms. Levitsky’s article provides a practical, proactive approach to plan and implement a large-scale MEP repair or replacement project in a high-rise building to minimize costs and disruptions.
Because of the many alternatives that exist for MEP system replacements, the potential for significant disruption and inconvenience to building occupants, and the associated high capital cost incurred to undertake these projects in high-rise buildings, the article recommends a variety of key elements to ensure that a project delivers the intended result and best value.
A reprint of Mr. Swanson’s and Ms. Levitsky’s article can be found here.
Elara Engineering would like to remind our clients that the City of Evanston requires owners of commercial, residential and municipal buildings over 20,000 SF to track and verify (every third year by a professional) their building’s energy and water consumption using the Energy Star Portfolio Manager Tool. This includes apartment buildings, strip malls, schools, churches, hospitals, and condominium buildings. In addition, city-owned buildings, 10,000 SF or greater in size are required to comply. It should be noted that condominium buildings 20,000 SF to 50,000 SF are exempt from the ordinance. The deadline to update and verify your building’s data is June 30, 2020. At this time, the deadline for compliance with the city has not been extended, however there is still time to complete benchmarking for this year.
More information about this city ordinance and required compliance actions can be found here. Additionally, Kelsey Dale from our Hillside office would be happy to answer any of your questions and assist in verification of your building’s data. She can be reached at 708.236.0300 x147 or email@example.com.
Elara Engineering would like to remind our clients that the City of Chicago requires owners of commercial, residential and municipal buildings over 50,000 SF to track and verify (every third year by a professional) their building’s energy consumption using the Energy Star Portfolio Manager Tool. The deadline to update and verify your building’s data is June 1, 2020. At this time, the deadline for compliance with the city has not been extended, however there is still time to complete benchmarking for this year.
More information about this city ordinance and required compliance actions can be found here.
Additionally, Kelsey Dale from our Hillside office would be happy to answer any of your questions and assist in verification of your building’s data. She can be reached at 708.236.0300 x147 or firstname.lastname@example.org
In 2017, the City of Chicago created the Chicago Energy Rating System to improve the visibility and transparency of information required to be reported by building owners under the City’s 2013 Chicago Energy Benchmarking Ordinance. As most of Elara’s clients already know, the Energy Benchmarking Ordinance requires large buildings located in Chicago (≥50,000 SF) to report energy use once per year, with additional data verification required every 3 years.
Under the new Chicago Energy Rating System, the first ratings were assigned between late August and mid-September 2019 for energy benchmarking reports that were due on June 1, 2019. Now that the first ratings have been assigned, building owners will receive an initial six-month period within which they are required to post their Chicago Energy Rating Placard on site in a prominent location and begin sharing the rating at the time of listing for sale or lease.
How Chicago Energy Ratings are Assigned
Under the four-star rating system, four stars will indicate the highest energy performance while a one-star rating will indicate a poor energy performer. Properties that have not submitted energy benchmarking information will receive zero stars.
Approximately 85% of buildings that report their data receive a 1-100 ENERGY STAR score from the Portfolio Manager energy benchmarking software. These buildings will, based on their 1-100 ENERGY STAR score, receive between one and four stars on the four-star Chicago Energy Rating System. Buildings with one, two, or three stars will be able to earn an additional star if they have improved by at least 10 points in the past two reporting years.
Approximately 15% of the reporting properties that are not eligible to receive a 1-100 ENERGY STAR score. These properties will receive an energy rating based on the building’s source energy use intensity (EUI), which is energy use per square foot, in comparison to national medians for properties of similar size and type. The lower the percentile for Source EUI, the better, as a lower EUI indicates less energy use per square foot. In these cases, the Chicago Energy Rating will be based on the following scale:
- 1st to 25th percentile for Source EUI: 4 Stars
- 25th to 50th percentile for Source EUI: 3 Stars
- 50th to 75th percentile for Source EUI: 2 Stars
- Above the 75th percentile for Source EUI: 1 Star
- Any building with one, two, or three stars with a 10% improvement in the past 2 years earns an extra star
What Building Owners Need to Do
- Ensure compliance with the reporting requirements under the City of Chicago Energy Benchmarking Ordinance.
- Make sure you have received your Chicago Energy Rating Placard which were to be mailed by mid-September 2019.
- Post your Chicago Energy Rating Placard and begin sharing – on an ongoing basis — your rating at the time of listing for sale or lease within the initial six-month grace period.
Additional information about the Chicago Energy Rating System can be found here.
Elara Engineering Associate Principal Matt Swanson, LEED AP, CEM has had the above titled article placed as the cover story in the Autumn 2019 issue of Chicagoland Buildings & Environments.
The article presents the proactive approach taken to lower energy costs at the existing 474 North Lake Shore Drive high-rise condominium building located in the Streeterville neighborhood of Chicago. Elara’s forward-looking approach implemented over several years by the 474 North Lake Shore Drive Condominium Association resulted in a 23% reduction in relative energy costs since 2007; a savings of $127,930 annually.
Beginning with Elara’s 2008 energy audit, the building’s Condominium Association maintained a constant focus on the energy performance of their building and continuously implemented energy conservation recommendations identified in the 2008 audit report, and subsequent reports in 2011 and 2015.
Consistent with Elara’s recommended strategy, projects that addressed “low hanging fruit” such as controls and VFDs that have a short-term payback and reduce the overall load of the building systems, were implemented first. This strategy paid dividends during a 2016 chiller plant replacement. Reduced demand of end-user systems (e.g., AHUs, exhaust fans, etc.) from previously recommended energy efficiency projects allowed for the installation of new chillers that were smaller in capacity; resulting in both lower initial and operating costs. The associated savings allowed the Condominium Association to fund other energy efficiency upgrades.
In total, all of Elara’s recommendations that were implemented represented an incremental cost of $900,000 with a payback of less than 10 years. Additionally, $58,275 was obtained through utility incentive programs to assist in funding the projects as a result of the energy efficiency improvements implemented.
A reprint of Mr. Swanson’s article can be found here and more detailed information about Elara’s 474 North Lake Shore Drive Project can be found here.