Bladder insulation

Bladder insulation which is adapted to be inserted within the wall cavities of existing buildings is disclosed which provides for high quality insulation having a high R value. The invention describes a bladder or impervious bag constructed of two thermoplastic sheets of material hermetically sealed at both ends and on each of the sides. The preferred film used herein is urethane although polyethylene of from 4 to 15 mils in thickness may be employed on the inside and/or the outside of the bladder. This bag can be inflated within the wall cavity and filled with various insulative materials and/or pressurized with various fluorinated hydrocarbon gases. The various insulative fill materials used may be, but to be all not inclusive, vermiculite, mineral wool, microballoons of either glass or plastic, and eggcrates, or any combinations of these materials. An expandable eggcrate device constructed of thermoplastic material in a collapsed state and sandwiched between two layers of thermoplastic material that expands into an eggcrate when inflated creates a semi-rigid plastic material. The gaseous medium used in this invention consists preferably of fluorinated hydrocarbon gas, CO.sub.2 or N.sub.2, and has a pressure of up to one and one-half pounds, or a vacuum of 16 to 18 inches of water, which is about 0.65 pounds vacuum, or about 0.05 atmospheres. The invention also includes a means for inserting the bladder with the wall of a structure and rigidifying the bladder by adherence to studs or a polymerization technique to form a polyisocyanate on the interior side of the bladder.

BACKGROUND OF THE INVENTION 
A number of bladder insulation techniques are known from the prior art 
references listed below: 
U.S. Pat. No. 2,252,578 to Powell discloses a method of insulating 
buildings. A flexible bag is placed inside a wall in a collapsed state. 
Thereafter insulation is poured into the bag to fill the space between the 
inside and outside walls. The bag is not inflated with air. 
U.S. Pat. No. 3,918,512 to Kuneman discloses a window sealing arrangement 
wherein an inflatable bag is placed between the inside and outside windows 
in a storm window arrangement and then inflated. An insulating air space 
is thus provided. 
U.S. Pat. No. 4,155,208 to Shanabarger provides for a sealed air space 
between studs in a building wall. FIG. 4 of that patent illustrates the 
insulating roll which is made up of a plurality of elongated elastic bags 
having air trapped inside. 
U.S. Pat. No. 4,182,085 to Elson features an inflatable envelope of gas 
impervious material which is inserted in a building wall and inflated. It 
contains heat insulating material within the envelope. 
German Pat. No. 27 08 733 discloses a method of attic insulation whereby a 
multicelled roll of plastic is rolled out in the attic, inflated with 
compressed air and filled with blown-in insulation. 
Other U.S. Pat. Nos. of interest to this development include the following: 
4,172,915, 2,971,616, 3,264,165, 4,172,345, 2,896,272, 4,182,085, 
3,854,253. 
SUMMARY OF THE INVENTION 
This invention relates to an improved insulation material for existing 
structures and consists of polyurethane and other common insulation 
materials which may be employed therein. 
An impervious layer of polyurethane, polyethylene or polypropylene from 
4-15 mils in thickness is utilized on the inside of the wall, and a layer 
of film of the same material is utilized on the exterior side of the wall. 
The bladder is filled with an insulating material and a slight pressure 
consisting primarily of fluorinated hydrocarbon gas, carbon dioxide or 
nitrogen. 
A vacuum is used when the bladder is fixed within the studs by means of 
adhesive or by rigidifying the bladder by means of a polyisocyanate 
process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
This invention is directed to an improved insulation material for use in 
existing buildings, one example of which is shown in FIG. 1. In this view 
there is an impervious layer of polyurethane, polyethylene or 
polypropylene from 4-15 mils in thickness on the inside of the wall plus a 
layer of film of the same material on the outside of the wall. Of course, 
a material of substantially greater thickness may be used, but it would 
cost more and have reduced permeability as well as a tendency to 
puncturability whenever a nail or working tool is used. 
FIG. 1 illustrates a section of bladder insulation with its outside at 10 
and inside at 11 and a bladder valve at 12. The bladder is rolled up or 
assembled in a known manner and inserted through an opening in the wall 
and positioned therein by inflation of the bladder, more particularly 
shown in connection with FIG. 2. Various materials are then used as 
fillers as shown in FIG. 3. These materials may be vermiculite, mineral 
wool, microballoons of either glass or plastic, perlite, or eggcrate 
structures of polyurethane or cardboard. It is important that the 
insulation used must be of good quality material and that a gaseous medium 
surround the insulation. Such a gaseous medium might consist of carbon 
dioxide, fluorinated hydrocarbon gas or nitrogen, with a pressure of about 
one and one-half pounds, although, in certain instances, a vacuum may be 
used of about 0.65 psi. 
A section of the wall with the insulation between each of the studs is 
shown in connection with FIG. 4. One stud is shown at 14 and another at 
15. Shingles or other outside materials are generally shown at 16, and the 
inside wallboard at 17. Between the studs is the bladder insulation, the 
inside of which is shown at 11 and the outside at 10. The insulation 
itself is shown at 19. 
FIG. 5 illustrates another longitudinal cross section of a wall with three 
studs and two full panels as well as a portion of two other panels. 
Horizontal framing members are shown at 19. One of the vertical studs is 
shown at 20 and the top horizontal framing member at 21. One panel, which 
was described earlier, is featured at 22, while another panel is at 23. 
Various methods are used to install panels, one method of which is shown in 
connection with FIG. 6. Here, a spray nozzle, which is generally indicated 
at 24, is positioned between the studs and between the outer and inner 
walls. For convenience, these are indicated as the outside shingles 16 and 
the wallboard 17. A spray nozzle 24 sprays adhesive in a controlled manner 
to the end of the stud and to the outside and inside by means of a 
directed nozzle which includes three openings therein. The nozzle is 
passed substantially along the full length of the space between the studs 
and adhesive is applied on the studs, on the outside wall and on the 
inside wall of the cavity. In like manner, the bladder insulation is 
inserted between the studs and inflated to press the bladder against the 
studs for securing it in position. After a time, when the adhesive has 
set, the bladder is ready for filling with a fill material. Either 
pressure or vacuum may be placed upon the bladder to complete the assembly 
for the bladder insulation. 
FIG. 7 is a cross section of a portion of the same wall as illustrated in 
FIG. 6. The insulation is now in place and secured against the inside and 
outside walls. The insulation in this view is shown at 30 with the outside 
wall at 31 and the inside wall at 32. 
In the first example of this invention an impervious film material is used 
consisting of polypropylene, polyurethane or polyethylene. A thickness for 
this material is chosen as 15 mils although it may be as low as 4 mils. 
The material is then inserted in the wall of a building through a suitable 
opening which is normally accomplished from the outside, after which it is 
filled with air, for example. Filler material for the bladder is then 
inserted in the wall, which may be vermiculite, mineral wool, 
microballoons of either glass or plastic, perlite or eggcrates and has 
already been assembled in the bladder prior to manufacture. Upon expansion 
with air or gas, the material stretches out and fills the space between 
the studs. 
Following the insertion of the filler material, a gaseous medium is 
inserted to remove the air. This gaseous medium is preferably carbon 
dioxide, fluorinated hydrocarbon or dry nitrogen and has a pressure of 
about 11/2 psi. 
A further method of inserting and fastening the bladder insulation within 
the wall is by the use of an adhesive (see FIG. 6) which coats the space 
between the studs. The bladder is inserted between the walls, and a 
gaseous medium is employed along with insulation of the type previously 
disclosed. The adhesive sets and bonds the wall to the stud. Instead of 
just using pressure in the bladder, a vacuum may be utilized. A typical 
amount of vacuum is 16-18 inches of water, which is equivalent to about 
0.65 psi, or 0.5 atmospheres vacuum. 
In still another method, the bladder may be rigidified by extruding in a 
factory polyurethane materials that are partially cured, which are made 
generally by a reaction injection molding technique. The bladder is formed 
and filled on site with 4,4' diphenylmethane diisocyanate gas to rigidify 
the inside layer of the bladder, and a small vacuum of the order described 
above is used to provide good quality insulation. 
To aid in rigidifying the bladder, polyurethane eggcrates are placed within 
the bladder. As the film rigidifies the bladder, the eggcrates, which fill 
the spaces between the studs, are directed in position and secured to 
portions of the inside face of the insulation by means of the formed rigid 
polyurethane material made by the curing isocyanate gas. 
For security, filler material is then placed in the bladder, i.e., 
vermiculite, mineral wool, microballoons or perlite, although vermiculite 
and mineral wool are the preferred materials. Microballoons may be used 
but are much more costly than the other materials. If the eggcrate 
structure is used, fill material is not necessary and therefore not 
employed. The vacuum in this instance is about 0.65 psi. It should be 
understood that if impervious films are strong and the attachment to the 
walls and rigidification of the film are adequate, higher vacuum is not 
required. When using vacuum, it is important not to use a material that 
would generate off-gas particularly during the aging process. Polyurethane 
is most desirable for this reason. 
The invention has been described with reference to the preferred and 
alternate embodiments. Obviously, modifications and alterations will be 
readily apparent to others upon the reading and understanding of the 
specification. It is the intention to include all modifications and 
alterations insofar as they come within the scope of the appended claims 
or the equivalents thereof.