All of the specification paragraphs are generic in their descriptions and there is never any need to change those descriptions as they apply to all installations. If you have accepted our explanations and like our wording, your specification would appear exactly as shown here. The paragraph sections are in the format of the American Architectural Association. If this is not the format or the language you want to use, the specification paragraphs can be readily rearranged or edited. Once these paragraphs are in place, there is no need to change them from job to job or to omit or delete because the only isolators that are used are those that are called out on your equipment schedule. In our presentation, Schedule 4.01 is part of the specification on the last page. If you prefer keeping this schedule as part of your drawings, in 4.01 write “Equipment and Isolator schedule may be found in the drawings.
Schedule 4.01 is not really something you are adding. Most plans and specifications already have an equipment schedule. The change is just the addition of the two columns which are headed Vibration Isolation. On the lefthand side we have a specification paragraph letter or letters, and on the right the static deflection. In most cases, the same isolator is recommended for a class of equipment in all locations. However, depending on the size of the equipment, the sensitivity of the structure and the occupancy of the building, a deflection must be selected by you to best fit the particular project.
The selection guide provides this information. HVAC equipment is listed on the left. We reference the vibration isolator by the first letter in the columns under “Isolation and Deflection Criteria”. The letters refer to the specification paragraphs. The second letter may reference the paragraph on base configuration. When there are three such letters, the first is always a vibration isolation device, the second the type of base, the third the type of flexible connector.
The next column over is the minimum isolator deflection in inches and millimeters. The two new columns on your schedule completely describe the isolation package for any machine listed in the schedule. There are the letter designations that refer to the specification paragraphs, and then the deflection that is to be used with the isolation device.
There are five choices across. Up at the top under “Isolation and Deflection Criteria” there is a description of where the machinery will be located in terms of a ground supported slab or basement or an upper floor with a given floor span. Most buildings have 30 foot(9 meter) floor spans, so most specifications are based on this deflection column. Should you have a 30 foot(9 meter) floor span, but it is a non-critical application, you might select from the 20 foot(6 meter) column. Vibration reduction will be somewhat poorer, but the cost lower. If the span is 30 feet(9 meter), but you are very concerned, you might make selections from the 40 foot(12 meter) column, because the additional isolator deflection provides a higher vibration isolation safety factor. In general, the column showing the actual floor span is very conservative to begin with and needs no further consideration.
The Sample Isolation Schedule is typical of how you would show your selections. Whether you require no isolation because the equipment is in a remote equipment room away from the building or it is something like a fire pump and you are not concerned when it is in operation, you indicate no isolation by writing “None” in the chart. All the information in your schedule is taken from the isolator selection guide. When using this method, you have the opportunity to consider all of the equipment and there is little chance of leaving things out. On some jobs you will not to refer to all the isolators, but it is much easier to leave them in than editing the specification each time. The only isolators that are used are the ones that you include on your equipment schedule in the vibration isolation columns.