Mechanical, electrical and plumbing systems represent a large fraction of building development costs. However, smart design decisions can make these installations less expensive without reducing their performance. In fact, performance improvements can often be achieved simultaneously with cost reductions.
Some MEP components, such as chillers and boilers, are expensive individually, but their cost can be optimized with a single design decision: selecting equipment with the right capacity according to the building load. On the other hand, piping and duct systems connected to MEP equipment have a low cost per meter, but considerable expenses add up if we consider an entire building.
With any construction system that uses tubes or air ducts, there is an opportunity to achieve savings through optimizing the layout. Ideally, you should achieve full building coverage with the shortest possible length of piping and ductwork. The same principle applies to electrical installations, where the circuit passes through conduits and other types of channels.
Optimize the cost of your MEP installations.
The easiest way to optimize piping, duct and conduit costs is to hire a qualified MEP engineering firm to design your project.
Reducing the total length of piping
The most common use of pipes in buildings is to supply drinking water and collect wastewater. However, piping also has applications in fire protection and HVAC systems, and the following are two examples:
- Automatic sprinkler systems use piping to deliver water to each sprinkler head. Fire protection piping is typically painted red.
- Many HVAC system configurations include hydronic piping, using water to provide or remove heat from indoor areas. For example, a refrigerator does not cool air directly; it cools the water and piping transports the chilled water to cooling coils in the air handling units.
The total length of piping required for a building can be significantly reduced with intelligent placement of equipment and mechanical rooms. The opposite also applies: poor equipment location leads to excessively long pipes, which are much more expensive.
Piping costs for automatic sprinkler systems can also be reduced with an optimal layout. Ideally, your installation should use the fewest sprinklers that provide full coverage for the building.
- New construction offers an excellent opportunity to optimize coverage, as fire protection engineers can work closely with the architect as the building is designed.
- Optimization is also possible in existing buildings, but fire protection projects must adapt to existing architectural features.
Consider that water loses pressure as it flows through the pipe, due to friction between the moving fluid and the inner surface of the pipe. Friction losses increase when the piping system is too long, which leads to higher pumping costs and electricity expenses.
Optimizing air duct coverage
Ductwork typically shares space above the ceiling with other MEP components. Air ducts are bulkier than piping, and optimizing the layout not only provides cost reductions but also space savings. When air ducts are selected correctly, you also minimize noise and vibration problems.
Just as longer pipes increase pumping expenses, longer air ducts lead to an increase in fan power. Because Northeastern states like New York and New Jersey have kilowatt-hour prices above the U.S. average, pumping and ventilation losses have a noticeable effect on energy bills.
Savings on electrical wiring and conduit
Electrical design also offers many opportunities for layout optimization. As with pipes and ducts, intelligent equipment placement leads to shorter circuits. However, in the case of electrical installations, it is also possible to reduce costs with energy-efficient wiring and conduits.
- Energy efficiency reduces the energy consumption of an electrical installation. As the supply voltage is constant, this is reflected as a reduction in current.
- The lower current allows the use of smaller conductors at a lower cost per meter.
- In turn, smaller conductors fit into smaller conduits, which are also cheaper.
If you are using energy efficiency measures in an existing building, there is no need to reduce circuit capacities. Oversizing causes extra spending on new construction and major renovations; however, when an existing circuit is already oversized, the cheapest option is to simply leave it in place.
Although the savings from reducing an individual circuit are typically small, the cumulative effect is significant for a large building, especially when selecting electrical service equipment. The cost difference isn't much between 30 feet of #12 and #10 wiring, but a 500 kVA transformer is significantly cheaper than a 750 kVA unit.
Conclusion
The total cost of ownership of a building can be drastically reduced with smart decisions during the design phase. Significant savings can be achieved on ducting, piping and wiring by optimizing the layout of MEP installations. Design services provided by professional engineers can be considered an investment as they reduce construction ownership costs.
