There are provided a heat insulating tool kit for
piping, which can easily be attached to and detached from a
piping in a limited space repeatedly and fixed in a stable form, can be attached so that a heating surface is in
close contact with the outer
peripheral surface of
piping so that heat is conducted efficiently, which results in no overheating of heated portion, can be subjected to
temperature control stably, and can be used in a clean room etc. because
dust particles scarcely occur, and a heat insulating construction using the heat insulating tool kit. The heat insulating tool kit includes a piping; a band-shaped heat insulating unit which includes at least a heat insulating material and preferably a
heating element and is wrapped with a heat-resistant resin film; a support cover consisting of a tubular element of a C-shaped cross section having a slit-shaped opening over the total length in the axial direction of the tubular element; and preferably an external cover of almost the same shape as that of the support cover. The heat insulating construction is formed as described below. The heat insulating unit is housed so that the non-heating surface of the heat insulating unit comes into contact with the tubular element inside wall of the support cover 14, and in a state in which ear portions at both ends of a heat insulating portion are pulled out of the slit-shaped opening, the butting portion at both ends of the heat insulating portion, that is, the slit-shaped opening of support cover is pressed on the piping, by which the piping is covered with the heat insulating portion and the support cover. Next, the opening portion of external cover in a widened state is pressed on the slit-shaped opening side of the support cover, by which the heat insulating unit and the support cover are collectively covered with the external cover 15.