Engineering at its Best




As the world concerns itself with climate change, and AEC professionals strive to offer real solutions, it is reassuring to know we already have the knowledge and many of the tools needed to combat the effects of global warming. Building Information Modeling, the Revit® platform, offers the data richness and integration to begin providing design and analysis tools for a better-built environment. Energy modeling using computer software has become embedded within each project to analyze energy consumption and use this analysis to guide key design decisions.  Better decisions up front result in performance and energy savings for the life cycle of a building.  Energy modeling also plays a crucial role in meeting LEED documentation requirements.  The D&D Engineering staff is fluent in software such as Integrated Environmental Solutions (IES), Ecotect™, Trane® Trace™ 700, and eQuest®.




The mechanical engineering staff has extensive experience in the analysis and design of heating, ventilation, air conditioning and refrigeration systems.

Central cooling and heating plants including chillers, boilers, cooling towers, primary/secondary variable speed pumping systems, energy recovery systems, and thermal storage.


Air handling and distribution systems including constant and variable volume systems, as well as underfloor air distribution.


Data center and critical applications design using the latest technology including in row cooling.



The D&D Engineering electrical engineering staff has experience in designing low voltage electrical distribution, back-up, and sustainable systems to accommodate the rapidly changing energy and code demands.

Low voltage electrical power distribution systems are designed to deliver the highest level of safety for personnel and property, as well as a standard of reliability appropriate for a particular application. Systems are also designed so they can be easily upgraded for future load demands and power conditioning requirements of rapidly evolving technologies. Electrical designs provided by D&D Engineering place a premium on energy efficiency, economy, flexibility, and ease of maintenance. Our designs also satisfy any regulatory and budget constraints of a project. System design, analysis, and documentation utilize computer modeling and simulation techniques that also can be applied to analyze voltage drops, system losses, short circuit conditions and system circuit protective device coordination.


On-site, standby power generating equipment is designed for emergency and critical power demands. These systems are highly reliable and flexible with adequate capacity to serve all necessary loads. Generator loading and performance are analyzed to take into account sequenced energizing of loads, stating inrush, and generator voltage dip. Uninterruptible Power Supply (UPS) is provided for life support, life safety, and other critical applications.


Lighting design or support throughout the design process with photometric calculations and daylighting analysis is a service that D&D Engineering provides.  Minimizing the quantity of fixtures and using appropriate lamping can provide initial cost savings along with optimizing energy savings for a facility.


Fire alarm/life safety systems are designed to include smoke and heat early warning detection, audible and visual signaling appliances, fire fighter telephones, annunciator panels, voice communications, fan status indicators and smoke controls. We have many years of experience in developing systems utilizing the latest technologies.


Technology systems and infrastructures designed by D&D Engineering include multimedia and video, telecommunication, computer and data network, broadband and CATV, voice and data cabling distribution systems, wireless and personal communication service, as well as security and access control.



From a sustainability perspective, total water system management may be the most critical feature of a building.  Our engineers understand this importance and create designs that provide water-efficient solutions while maintaining performance.  Plumbing engineers are involved with systems that overlap into the mechanical, civil, and chemical engineering disciplines and help influence the water efficiency, sustainable site, energy, and pollution systems of a facility.  Plumbing system design incorporates all aspects of the plumbing system, including:

Potable water building supply and distribution piping.  The objective in designing the water supply systems for any project is to ensure an adequate water supply at adequate pressure to all fixtures and equipment at all times and to achieve the most economical sizing of the piping.


Plumbing fixtures are evaluated by the plumbing engineer to determine that the type, arrangement, space requirements, and standards are met.  Fixture traps are also evaluated to ensure that the device provides a liquid seal that will prevent the back passage of air without affecting the flow of sewage or waste through it.


Sanitary drainage refers to the discharge from the fixture through pipes and stacks to a sewage system.  Sanitary piping is installed in a building for the purpose of removing waterborne wastes. Flow of air is the primary consideration in the design of a venting system for the ventilation of the piping and protection of the fixture trap seals of a sanitary drainage system.  Since air is of such primary importance, it is essential that the plumbing engineer be familiar with the physical characteristics that are pertinent to its behavior in a plumbing system.


Storm water drainage and site drainage.  Storm water is considered to be rainwater, surface runoff, groundwater, subsurface water, or similar clear wastes, exclusive of sewage and industrial wastes.  Every building must have adequate provisions for draining water from roofs, paved areas, courts, and yards.


Medical gas and medical vacuum systems include the pipes, fixtures, and other apparatus for medical gas, anesthetic waste gas, or vacuum systems. These systems also include anesthetic waste gas recovery, medical air nitrous oxide, oxygen, nitrogen, helium, carbon dioxide, and other gas mixtures.


Plumbing Equipment including water heaters, hot water circulating equipment, sumps and ejectors, water treatment equipment, booster pump systems, and backflow equipment.


Private water supply and private sewage disposal applications are for remote areas where sanitary sewers are not available and areas with inadequate water supply.



Our fire protection engineers incorporate the application of science and engineering principles to protect people and their environments from the destructive effects of fire and smoke.  Fire protection engineers identify risks and design safeguards that aid in preventing, controlling, and mitigating the effects of fires.  Fire protection design incorporates all aspects of fire suppression, including:

Automatic sprinkler systems including wet pipe, dry pipe, pre-action, deluge, and special sprinklers (large drop, ESFR, water spray or water mist). Automatic sprinklers operate automatically when the heat-activated element is heated to its thermal rating or above, allowing water to discharge over a specified area.


Gaseous system designs use inert gases and chemical agents to extinguish a fire. Gaseous fire suppression systems (also called clean agent fire suppression) including carbon dioxide, inergen,  FM200, and sapphire extinguishing systems for computer rooms, clean rooms, and telecommunication facilities).


Fire fighting foam systems cool the fire and coat the fuel, preventing its contact with oxygen, thus suppressing the combustion.  Foam system design includes protein and fluoroprotein,  AFFF, FFFP, and high expansion type systems.


Design of private supply systems, including electric motor and diesel engine driven fire pumps, jockey pumps, water storage tanks, underground water mains, and hydrants.


Fire pump and standpipe system sizing.


Analysis of hydraulic calculations, hazard classifications, and fire codes.