Polyiso insulation installation

On mechanical systems operating above ambient temerpatures, vapor retarders or barriers should not be required. Consult a qualified insulation engineer if there is cycling below ambient conditions. Mastics, sealants, and adhesives should be designed for anticipated temperatures. All piping should be free of foreign substances and free of surface moisture or frost prior to the application of insulation. All insulation material should be delivered to the project site in original, unbroken factory packaging labeled with product designation and thickness.

The shipping package should not be air-tight. Shipment of materials from the manufacturer to the installation location should be in weather-tight transportation. Insulation materials delivered to the job-site should be stored so as to protect the materials from moisture and weather during storage and installation.

Insulation material should be protected from sunlight to avoid exposure to UV light from the sun. All testing including hydrostatic, air pressure, or NDT of piping and equipment systems should be completed prior to the installation of the insulation system.

Thickness calculations may be performed using the 3E Plus insulation thickness software program that uses heat flow algorithms based on ASTM C Additionally, at the client's request, Dyplast's certified staff will run basic calculations using 3E Plus if the client provides and takes responsibility for environmental and process inputs. Stagger all longitudinal joints between the inner and outer layers. All butt joints between the inner and outer layers should be staggered between 6 and 18 inches.

Refer to Figure 1 in Appendix B. ISO-HT foam insulation may experience a discoloration on the inside surface where it is directly exposed to the pipe surface when the operating temperature is constantly in higher temperature range.

This discoloration does not affect the performance of the insulation. A pipe coating system may be recommended to minimize the likelihood of pipe corrosion.

Consult Appendix A for conditions where pipe coating systems are suggested. Where an anti-corrosion pipe coating system is on a surface to be insulated, drying time should be allotted per the coating manufacturer's recommendation prior to applying the insulation. All flanges on pipe, ducts and equipment and all valves to the packing gland should be insulated with the same insulation material and thickness as applied to the pipe or equipment unless the engineer indicates otherwise.

On bolted flanges, the permanent insulation on pipe and equipment should terminate 1 inch plus a bolt length from the flange to facilitate bolt removal unless the flange location prevents this spacing. Any damaged insulation that may create voids should be replaced with new insulation. Filler material is not acceptable. Each pipe should be insulated as a single unit, and adjacent lines should not be enclosed with a common insulation unit, unless approved by the owner's engineer.

Store the bun stock at normal shop indoor conditions for at least 24 hours before fabrication. For best fabrication quality, it is recommended that ISO-HT buns be fabricated into pipe shells in the 36 inch bun length direction to maximize flatness. For diameters too large for fly-cutting or routing, the pieces should be fabricated in two halves with each half made up of mitered sections.

ISO-HT insulation should be applied with the piping and component system at ambient temperature, and immediately secured with filament tape. ISO-HT foam insulation should be applied using two half-sections to the largest commercially available diameter.

For larger sizes curved segments may be utilized. Begin installing the insulation sections on the pipe with a full length section followed by a half-length section so as to facilitate having no seam adjacent to another seam. The longitudinal joints should typically be at 9 o'clock and 3 o'clock positions. When additional layers of ISO-HT insulation are required, each should be applied in the same manner as the first layer with circumferential and longitudinal joints staggered between joints of the preceding layers, so that no two joints coincide.

Tightly align all butt as well as longitudinal joints so as to eliminate gaps, except of course as may be appropriate for applications such as expansion joints. Single layer insulation should be applied to piping with all joints sealed full depth with joint sealant and spread to uniform thickness so that joints appear tight and uniform, without excess sealant escaping the joint.

In a double layer insulation system, the inner layer should not be installed with sealants unless otherwise specified by the engineer. In double layer systems it is common practice that inner and outer layer remain independent of each other so as to allow movement between the layers. Insulation should be secured with fiber reinforced tape per Figure 4 on 9-inch centers, with such tape also no greater than 3 inches from butt joints. Where the insulation O. Elbow insulation els should be routed from ISO-HT insulation to the same thickness as the pipe insulation.

Install pre-fabricated insulation fittings on elbows, tees, and valves. Where it is not possible to use commercially routed insulation els, fabricate the covers using clean cuts and miter counts in accordance with ASTM C Secure the half-sectional miters with insulation adhesive and rasp the heal of the miters to accommodate installation of the outer covers.

Where the pipe insulation terminates, such as at valves and flanges, seal the exposed insulation by applying two coats of a mastic specified by the engineer, with open weave glass fiber reinforcing cloth between the coats.

The total dry film thickness should be per the mastic manufacturer recommendation. Unless otherwise specified by the engineer, the mastic system should cover onto the bare pipe 1 inch minimum and extend over the insulation O. Valves and flanges should be insulated to the same thickness as the pipe insulation using enlarged pipe insulation.

The valve and flange covers should extend over the pipe insulation equal in thickness to the pipe insulation or a minimum 2 inches or as otherwise specified.

Fabricate the covers using a high temperature joint adhesive. Where the pipe support is directly on the pipe, such as with a clevis type hanger, insulate the hanger in the same manner as a flange. Bottom insulation sections in hanger saddles should be have the necessary resistance to compression on pipe diameters 4" and greater.

Depending on the saddle length and span chosen for a specific job, lower density insulation such as ISO-HT insulation may be sufficient to be used as saddle insulation. Consult a competent insulation engineer for your specific scenario. On vertical piping, to prevent the insulation from sliding down the pipe, install insulation support clamps at the bottom of the vertical run and above flanges with a recommended spacing of 1 inch plus a bolt length unless otherwise specified.

The clamps are not necessary where the field team has provided support tabs welded to the pipe. In the unlikely event vapor barriers are appropriate, they may be applied in the field if approved by the engineer given the various factors such as weather, experience of labor, and so forth, but Dyplast recommends that vapor barriers be factory applied by a qualified fabricator.

Again, in the unlikely event a vapor barrier is required a part of the system, vapor barrier film should be cut to length longitudinally and wrapped around the circumference of the pipe with lap joint, and installed facing downward avoiding the placement of the joint at the top or bottom of the pipe. Lap joint should be sealed with either self-sealing tapes or a liquid adhesive.

Butt joints should be covered with vapor barrier tape. Spiral wrap configuration can be used in lieu of the above installation. Spiral wrapping will require adhesive placed on one edge of the vapor barrier as it is wrapped over the previous layer.

In the unlikely event a vapor barrier is specified, with factory applied vapor barrier film, the longitudinal lap joint is to be sealed with SSL tape. In the unlikely event a vapor barrier is specified and as stated above, solvent or water adhesives may be used to attach the vapor barrier film to the outer surface of the ISO-HT. Refer to the manufacturer's vapor barrier installation guidelines. Consult adhesive manufacturer's literature for instructions on handling adhesives including required operating temperatures.

Elbows and fittings should be wrapped with vapor barrier tape or covered with a mastic type vapor barrier product. If using mastic type vapor barrier at fittings and elbows, form mastic so that fitting covers can be applied true and tight. Any underground vapor or "weather" barriers should be protected with a metal jacket that is puncture resistant. Such protection should be continuous around the pipe and have chemical resistance to expected ground water contaminants. If required, elbows and fittings should be wrapped with vapor barrier tape or covered with a mastic type vapor barrier product.

Contractor should generally not install jacketing with polyurethane foam fill in lieu of a vapor barrier at fittings and elbows without special approval by the engineer. If vapor stops are requireed, they should be used on either side of valves frequently removed for servicing, valve stations left exposed, or odd fittings, elbows, tees, etc.

Install per detail in Figure 6 in Appendix B or an approved alternate design. Banding for jacketing should be 0. This method takes more time but will be slightly more accurate especially on smaller jobs. Now you know how much polyiso you need per layer but you still need to figure out what kind of iso your going to buy. If roofing membrane you are using is adhered you're going to need an iso board with a fiberglass facer. Hint: Watch out for deficit freight charges and fuel surcharges.

Deficit freight can apply when your order doesn't fill up an entire semi-truck load regardless of how many truck loads you are buying of iso. You should definitely add these charges to any cost comparison you do between venders. If your job involves a tapered ISO package you may want to consider letting your vendor make a shop drawing and do a take off for you. This will prevent a phenomena call thermal bridging where a roofing membrane will condensate on the bottom or warm side of the building instead of the top side of membrane.

Hint: If the polyiso is going down mechanically attached with screws and plates , you can loose lay the first layer in place without putting screws and plates in it. Then lay the second layer and screw and plate it down. The screws and plates from the second layer will hold the first. Make sure that your screws are going at least an inch into the deck. If you are required to adhere you polyiso board consider using one of the many foam adhesive kits on the market. These kits typically consists of two disposable canisters, one of low rise foam and one of adhesive.

A hose and gun assembly mix the two materials together as they come out of the gun tip to form beads or lines of adhesive to lay the iso in. The installation is clean and fast. So fast in fact that per every kit you have a man spraying you will need two more men carrying and laying in ISO.

If your Polyiso is going down mechanically attached, ditch the cordless drills or impacts and invest in corded screw guns. They will take a little getting used to but will double or triple your production, especially on larger jobs. There are many types and models on the market but the Dewalt has proved itself on our crews time and time again.

Polyiso is difficult to trim up with any amount of precision so trying to cut in ISO. Not to mention the time it takes to cut each board twice. Hint: Use a utility knife to cut, score, and break thin iso but for thicker pieces use a ISO knife or skill saw to make cuts faster and cleaner.

Polyiso is one of the best, most efficient way to insulate a building.