What Air Duct Design is Right for Your Home?
Unless they're starting a home renovation project or replacing an outdated HVAC unit, homeowners probably don't give much thought to the ductwork running through their house. However, these air ducts are instrumental in heating, cooling, and ventilating the home. Every house is different and requires its own optimal duct design.
This article will explain the different types of duct designs and the many factors determining what configuration is right for any given home.
House Layout Is Key
Old-fashioned radiators and clunky window-mounted AC units are a thing of the past; now, the average home runs on central air. This means that one big unit controls the temperature and airflow of every room in the house. This unit is placed close to the center of a home's floor plan to minimize the distance between the air pump and the rooms. The longer the ducts, the harder the pump will work to deliver air throughout the house.
A centrally placed unit also helps ensure a symmetrical duct design, which aids in efficiency and overall comfort by distributing airflow equally across every room. Otherwise, the living room on one end of the house may be cold while the master bedroom on the other end may be warm and stuffy.
Some houses utilize a single central return vent, which can reduce efficiency by forcing airflow to return to the unit partially impeded by obstructions such as closed doors. Whenever possible, it's ideal for every room to have both a supply vent and a return vent, so that airflow can return to the unit unimpeded.
Different Duct Materials and Their Uses
Air ducts are made from a variety of materials. Different types of ductwork are employed for different purposes, but they fall into two basic categories - flexible and rigid. Flexible ductwork is made of a spring-like metal coil housed in malleable, insulated plastic. It is mainly used in tight, difficult spaces where rigid ducts won't work. While unavoidable in some cases, flexible ductwork is used sparingly, as too many corners and bends can drastically impede airflow and reduce the unit's efficiency.
Rigid ductwork for residential use is typically made from galvanized steel or aluminum sheet metal. These materials are non-porous and smooth, making them less likely to accumulate moisture, which can lead to mold or bacteria growth. Other types of rigid ductwork are made with fiberglass, either as fiberboard (a hard composite made from fiberglass strands) or as an insulating liner in traditional sheet metal ducts. These types are usually found in commercial buildings, and rarely in homes.
The Role of BTUs in Duct Design
Firstly, what is a BTU? It stands for British Thermal Unit, and it measures heat energy. One BTU is the unit of energy required to raise the temperature of one pound of water by 1 degree Fahrenheit. In regards to an HVAC unit, this measurement is usually expressed as an hourly rate (BTUs/hr) and is used to denote the unit's heating or cooling power. Duct design can impact the BTU output of the unit in several ways.
As mentioned before, airflow efficiency can suffer from distance, too many bends or elbows, and a lack of air return vents. Sections of ductwork installed in poorly insulated areas, like attics or outer walls, can also put a dent in efficiency. These factors can put a real strain on BTU output as the unit struggles to keep up with air loss and maintain the correct temperature in every room. This can drive up the utility bill and drastically shorten the lifespan of the unit.
When adding a room or desiring to eliminate any drags on the unit's efficiency, it's best to schedule an inspection with a trusted HVAC company.
About Swick Home Services
Swick Home Services has been serving Marquette, Michigan for over 40 years. They provide upfront pricing, on-time arrival, outstanding service, and guarantee quality and satisfaction on every job.
