This ROOF JACK 21 has some cosmetic damage incurred during shipping.  Item returned with flashing bent and top vent smashed down.  For detailed photos please click 'See Additional Images' above. This ROOF JACK 21 meets the full manufacturer's specifications, comes with the full manufacturer's warranty, and includes Alpine's premium guarantee.

For product specs and photographs of product in its original condition, click here.

This roof jack is the only piece needed to vent your mobile home furnace. For proper fit, measure from the base of the furnace to the flange on the top of the roof.  The roof jack can telescope within the range described for an exact fit.  To adjust roof pitch, see the accessories for the appropriate roof wedge.

Note: Hydroment Sealant is the only substance approved for installation of roof jacks.