The networks of aeraulic ducts convey considerable quantities of air at speeds which can create sources of noise and at a temperature different from the ambient temperature. Their insulation is a very important factor for the efficiency of the networks themselves. The cladding must be made with suitable materials that can provide acoustic insulation and at the same time avoid energy dispersion, the formation of condensation and comply with fire regulations.

Insulation materials KRAFT PAPER GLASS WOOL ROCK WOOL KRAFT PAPER CLOSED CELL ELASTOMERIC SHEATH CL.1
Finishing, coating:	stainless steel sheets aluminum sheets

Mattresses in rolls:

In mineral fibers, (glass or rock wool) glued on wired aluminum kraft paper

Following the  provisions of the law  regarding thicknesses and materials, the mat, cut to size, is applied to the circumference of the duct to be insulated with a single joint on the upper side, fixing it with high-strength adhesive tape and sealing all the joints with aluminum adhesive tape.

Sheaths in rolls:

Following the provisions of the law  regarding thicknesses and materials, the insulation is applied to the duct, which must be clean and dry. The material must be cut to size around the circumference or one piece for each side if the thickness exceeds 15 mm. With a brush, spread the special glue on both sides to be adhered. You can proceed with the coupling after the solvent of the adhesive has evaporated (about 7-10 minutes) taking care to avoid the formation of bubbles.

In the case of self-adhesive material, the sheet previously cut to size is applied to the clean and dry duct, always taking care to avoid the formation of bubbles.

To seal the edges and joints, aluminum adhesive tapes or the same insulating material are used.

On double insulation, the joints of the two layers must not overlap.

Finish:

Even these insulation systems require an external coating for an aesthetic factor or to be protected from mechanical wear and bad weather if placed outside.

Insulating materials lose their insulating properties if they absorb water, therefore special care must be taken to prevent infiltrations.

The ducts placed in technical shafts or hidden by false ceilings are usually installed with the insulation already applied in the factory using self-adhesive elastomeric sheaths coupled with a protective polyethylene or metal film.

A good outdoor finish that satisfies aesthetic and protection needs is done with aluminum or stainless steel sheets cut to size and folded for the corner joints placed on the channel and fixed with self-tapping screws or rivets.

All joints of the finish on the ducts exposed to the weather must be rainproof, sealed with suitable silicones and joined with stainless steel screws or rivets.