Residential Attic Ductwork Layout

Make the layout as symmetrical as possible with branch ducts spaced evenly along the trunk duct and each branch of similar length.

Residential attic ductwork layout.

Ductwork is simply an air delivery system. Number one is the heating and cooling load calculation using a protocol like acca s manual j or the ashrae handbook of fundamentals. Duct system design considerations part 1 by roger m hensley cms. Look at the following factors when assessing your aging ductwork design.

Most residential structures can accommodate one or more of these configura tions. Route ducts between joists in a basement if possible or over them if necessary. One of the most important jobs of the designer. Once all the system variables have been decided your hvac design professional can determine the most efficient ductwork design layout and calculate the correct duct size.

When were the ducts installed. To account for all the necessary factors many professionals use a tool called acca manual d. Often residential ductwork from the original construction was designed inexpensively and without much thought for longevity. It was new when the ac was put in 7 years ago.

The residential forced air duct system. Designing a duct system is important but there are a few critical steps that come first. There are six basic locations for supply duct systems in residential structures. Situate the air handler close to the center of the layout to minimize the length of ductwork spans.

Typical trunk and branch duct systems. Aging ductwork can compromise your system s optimum performance efficiency and air quality. Recently i had another hvac company come out and put in a new bathroom vent and they told me they believed the duct work was full of water. This type of system incorporates the use of a trunk line or series of rectangular ducts that act as a main supply channel throughout the house.

Up against the deck may be the worst place in the attic to. The most common design trunk line layout is provided in the illustration below. You ve got to know how much heating and cooling you need for each room in btu hr. This hvac for beginners section begins here with a discussion about forced air duct systems the basics the how and why of duct sizing.

A duct system located in an attic. Remember that article i wrote about ducts installed against the roof deck and how i said it was probably the absolute worst single location for installing ducts. Avoid any hot elements such as water heaters heater or stove. Place ducts on top of joists in a ceiling or attic.

From these trunk lines come branch ducts usually round that extend. The layout and installation of the duct system will incorporate these basic principles of good ductwork design. Well in the comments dave roberts a senior engineer at the national renewable energy lab nrel wrote about a paper he co authored last year and included a link to it.