We are turning our roof into an unvented roof assembly by raising the roof and blowing in SPF. We are planning to leave the existing vapor barrier down but remove the fiberglass batting and then adding 6" of SPF in all the cavities, to completely seal and insulate the house. Should we have any concerns about doing it "upside down" and not spraying the foam directly to the underside/sheathing of the roof? Insulation Spray Coating
Spray foam comes in two flavors, open cell and closed cell, and provides both parts of the building envelope - the insulation and the air barrier. The building envelope should completely surround the conditioned space, and the insulation needs to be in contact with the air barrier. Since spray foam is both insulation and air barrier, proper alignment of insulation and air barrier is guaranteed.
I've had concerns with foam in walls with only 2-3" and the resulting air space & convective currents. spray foam for walls is not one of my recommendations to my clients. instead foam sheathing to exterior of walls caulked,taped & sealed. conventional insulation & air tight drywall approach. a better and affordable wall with no extremely long payback like spray foam in walls.
Due to a wide range of nozzle shapes and sizes, the consistency of the paint can be varied. The shape of the workpiece and the desired paint consistency and pattern are important factors when choosing a nozzle. The three most common nozzles are the full cone, hollow cone, and flat stream. There are two types of air-gun spraying processes. In a manual operation method the air-gun sprayer is held by a skilled operator, about 6 to 10 inches (15–25 cm) from the object, and moved back and forth over the surface, each stroke overlapping the previous to ensure a continuous coat. In an automatic process the gun head is attached to a mounting block and delivers the stream of paint from that position. The object being painted is usually placed on rollers or a turntable to ensure overall equal coverage of all sides. Coating Services
For over a decade, Synavax™ has served as the preferred industrial thermal barrier insulation, energy saving, surface protection and asset protection coating, meeting the needs of multiple industries around the world, including pulp and paper manufacturing, food and beverage manufacturing, U.S. military, oil and gas, textile manufacturing and many others. Spray Coating