of these structures may be formed from a polymeric outer fabric 98 of polyester nylon or the like with an outer surface coating of pvc or the like disposed in wrap around relation to one or more layers of an insulating cellular foam 99 such as polyethylene foam or the like having a reflective coating of aluminum or the like on one or both sides oriented to face outwardly away from the interior of the tent by way of example only and not limitation one such insulating cellular material is believed to be available under the trade name low e u00ae sold by environmentally safe products inc having a place of business in new oxford pa such a construction is believed to provide substantial protection from intense outside heat while also containing warmth within the tent when heaters are being used of course virtually any other pliable fabric material may be used if desired as will be appreciated a significant benefit of a modular tent door consistent with the present disclosure is the ability to disengage segments making up the individual frame support members from one another and to then fold the structure by way of example only and not limitation each of the inboard lateral tube sections 22 23 and each of the outboard lateral tube sections 34 35 may be formed from multiple rectangular tube segments joined together in the manner as described in u s pat no 6 726 255 incorporated by reference.