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Light Commercial

For years I was thinking about writing a Light Commercial E-book and this idea never came to fruition...
Currently I'm working as a basement ductwork installer (ducter) for new residential applications, I'm 57, and I don't think that I will work as a light commercial installer ever again...

However, this idea of creating a comprehensive Light Commercial Ductwork Installation E-book is still alive and well and I hope that you can help me and others to make it work for everybody!

Participation Rules

If you decide to participate in the project:

  • E-mail me from this page
  • Choose a chapter (chapters) below and write your version
  • E-mail me your text with pictures
  • E-mail me improved text of the existing chapters and submit new pictures


  • If you are a ductwork installer you are going to improve your skills
  • If you are an owner of the HVAC Company you are going to have a great tool to educate your installers and you won't be alone!
  • Your name and your company's name (optional) will be printed right below chapter's title


  • Introduction
  • Tools
  • Materials
  • Curb and Flashing Installations
  • Roof-top Unit Installations
  • Plenum Installation
  • Ductwork Installation
  • Cold Air Returns
  • Heat Runs
  • Duct Sealing and Insulation
  • Duct (Smoke) Detector Installation
  • Bath Fans - Installation and Venting
  • Tube-type Infrared Heater Installation
  • Industrial Unit Heater Installation
  • Split System Installation
  • Energy Recovery Ventilator Installation

Any other chapter you may think of...

Ductwork Installation

When I was writing my “Ductwork Installation Guide” I've considered that the next guide is going to be to light commercial ductwork installation. But I wasn’t sure that there is a market for this kind of a manual.
However, nowadays a slump in the house market is driving HVAC companies from residential to light commercial installation. If you are working in this kind of company you may face a different environment and meet unexpected difficulties.
In general, light commercial installation is easer than the residential one, but it requires a different approach and an installer constantly finding different types of equipment and ductwork to install. Someone can do the work for 10 years and still find something new . Also different kinds of commercial buildings will make an installer run even a familiar system of ductwork differently. So, I've decided to create this page on my website.

The purpose of this page is:

  • To help newcomers with all my knowledge to accommodate a new profession.
  • To find out for myself if anyone actually needs this kind of help.
So, if you have any questions you can contact me on this page.

Here you can see some of the pictures which I took a long time ago for the “Light Commercial Ductwork Installation Guide”:

Supply duct                                         Supply duct above the sprinkle line    Y-branch

Connection of the supply duct to the plenum     Smoke detector                  Floor penetration

8” heat run                                          8” heat runs                                       Duct hanging

Bath fans exhaust pipe                      Diffuser connection                              Linear Register


“me and a guy are hanging commercial duct we both have 10+ years experiance between us when we come off the sicissor lift to look down at the duct work it looks twisted, we are very experienced at hammering duct work together, i dont get why it is twisted, the duct goes together easy with drives

So, here are several rules you have to follow when running the duct:

1. Hangers:

  • It’s always better to put all hangers on for the same duct size.

For example, if you have to install a 40’ of 30” x 14” duct and the distance between the trusses is 6’ you have to hammer on 6 pairs of hangers.

  • When you are measuring where the hangers should be cut, use an electrical conduit. They are always 10’ long and it’s very easy to put on an additional piece to length.

2. Ductwork:

  • When you snap a piece of duct together  it would be better if sides are matching, but it’s not a big deal if not.
  • Don’t put any screws in the seams.

3. Hanging the ductwork:

  • Every next piece of duct must be hung with the seam on a different side.
  • Don’t  screw a hanger to the bottom of the duct if there is a seam.
  • Don’t try to fix twisted ductwork until first transition or 90* is installed or all the system will be done.
  • If the system of the ductwork is twisted push the corners which are down and up from both sides.
  • Secure you job with the screws at the bottom of the ducts.
Space Cooling Load Calculations
                                                 Curbs Installations

Adjustable curb                                  Tall cone                                              Curb

Zoning, bypass damper                       Round ductwork                                  Zoning damper

I would like to know how the hangers are attached to metal beams. Also were the fire dampers should be in commercial applications.
Thank you.
Hangers or straps usually are attached by “Caddy strap hangers”. There are several types of them, but the most usable are shown on fig.1 (twisted) and fig. 2 (straight).

In order to attach the hanger strap to the “Caddy strap hanger” you have to fold approximately 1” – 1 ½” of it by using simmers, long nose pliers or hands, hook up the caddy strap and smash the hanger strap with the hammer. After that you just have to hammer it to the metal beam.
Because there are many types of metal beams: some of them are thinner and some of them are thicker, the “Caddy strap hangers” are made to fit thicker or thinner applications.

Split System Installation

So, as you can see during three years of existence of this page I did not receive too many questions, but it is not necessary means that nobody is interested in the subject. From my experience I already know, that people will buy a book, which is already written and available at a fair price.

During the last year I have wrote three books and improved and published the fourth one, as a result people are buying my Ductwork Installation Guide, Finished Basement Edition and separate chapters from the Kitchen Remodeling Edition and Energy Saving Edition books!

Therefore, if you are thinking that you have a high level of expertise in the Light Commercial Installation field or know someone who has, please contact me on this page. I am open to any kind of partnership with you or with your acquaintance with a purpose of writing a new book.


Energy Recovery Ventilator Installation

Lesson 1 - Register Box Installation
Learn how to install multiple register boxes on rectangular and spiral ductwork in commercial buildings.

Custom Designed HRV by John L.

This system was installed a few years ago as a prototype.
We sell a great little air to air heat exchanger for welding shops called "Keep The Heat".
Their only real drawback is that they only make one size of unit that exhausts about 1500 CFM.
If a customer needs more air flow they just add more units to achieve the desired total.

We ran into a few jobs where the customer simply didn't have enough room to install the required number of systems...

40 and 20 Ton Unit Replacements

Accurate Climate Services, LLC
10 W Broadway # 800K Salt Lake City, UT 84101
Copyright 2007 by Ductwork installation makes it easy to translate Spanish to English, and it also helps to translate English to Spanish for free.
Ingilizce Turkce ceviri, Turkce Ingilizce ceviri, ingilizce turkce cumle ceviri, ingililizceyi turkceye ceviri gibi tum dillerde dogru ceviri hizmetleri bu sitede.
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