US20080313985A1 - Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam - Google Patents

Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam Download PDF

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US20080313985A1
US20080313985A1 US12/107,161 US10716108A US2008313985A1 US 20080313985 A1 US20080313985 A1 US 20080313985A1 US 10716108 A US10716108 A US 10716108A US 2008313985 A1 US2008313985 A1 US 2008313985A1
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Prior art keywords
sheathing
beam members
polyisocyanurate
polyurethane
structural member
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US12/107,161
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English (en)
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Richard S. Duncan
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Honeywell International Inc
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Honeywell International Inc
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Priority to US12/107,161 priority Critical patent/US20080313985A1/en
Assigned to HONEYWELL INTERNATIONAL INC reassignment HONEYWELL INTERNATIONAL INC ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: DUNCAN, RICHARD S.
Priority to PCT/US2008/067857 priority patent/WO2009002910A2/fr
Priority to TW097123540A priority patent/TW200914695A/zh
Publication of US20080313985A1 publication Critical patent/US20080313985A1/en
Abandoned legal-status Critical Current

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    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B7/00—Roofs; Roof construction with regard to insulation
    • E04B7/20—Roofs consisting of self-supporting slabs, e.g. able to be loaded
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B7/00—Roofs; Roof construction with regard to insulation
    • E04B7/20—Roofs consisting of self-supporting slabs, e.g. able to be loaded
    • E04B7/22—Roofs consisting of self-supporting slabs, e.g. able to be loaded the slabs having insulating properties, e.g. laminated with layers of insulating material
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
    • E04D13/00—Special arrangements or devices in connection with roof coverings; Protection against birds; Roof drainage ; Sky-lights
    • E04D13/16—Insulating devices or arrangements in so far as the roof covering is concerned, e.g. characterised by the material or composition of the roof insulating material or its integration in the roof structure
    • E04D13/1606—Insulation of the roof covering characterised by its integration in the roof structure
    • E04D13/1668—Insulation of the roof covering characterised by its integration in the roof structure the insulating material being masses or granules applied in situ
    • E04D13/1675—Insulation of the roof covering characterised by its integration in the roof structure the insulating material being masses or granules applied in situ on saddle-roofs or inclined roof surfaces
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
    • E04D13/00—Special arrangements or devices in connection with roof coverings; Protection against birds; Roof drainage ; Sky-lights
    • E04D13/17—Ventilation of roof coverings not otherwise provided for

Definitions

  • the present invention relates to a method and structural member for securing a roof or an outer wall of a building against wind forces tending to lift the roof or outer side wall off the building.
  • Wood, wood composite, or equivalent structures predominate in residential construction, and when wood framing is employed the structure must be protected from forces developed by high winds.
  • Houses in the Caribbean or southeast coastal regions of the United States are situated in the pathway of annual hurricanes and as such, encounter hurricanes and/or tornadoes from time to time.
  • Such houses in the Caribbean area are typically constructed of cement blocks with a wooden top plate fastened to the top of cement block walls, for attaching a side walls and a wooden roof.
  • the roof is generally tied to the walls using a variety of steel connectors that connect the top plate to the walls.
  • 6,931,813 provides a roof-tie bracket system for bracing a wood framed roof of a building.
  • the structure is reinforced against the destructive wind forces by high strength brackets attached to every rafter where it joins the ceiling plates.
  • the roof-tie bracket is connected to the structure by way of a plurality of fasteners, such as nails or lag bolts.
  • U.S. Pat. No. 6,725,623 provides a method for controlling uplift on a roof with a plurality of clamps and transverse bars.
  • the transverse bars have a series of downward extending brackets each of which has a flexible foot to press down on the flat panels of the roof, thereby providing a structural brace to hold the panels down in a heavy wind.
  • 6,427,392 provides a method of roof reinforcement against hurricanes by placing an anchor assembly into a cavity in a wall and securing the anchor assembly to wall coverings enclosing the cavity around an anchorage area and then tying the anchor assembly to the roof structure.
  • U.S. Pat. No. 5,890,327 teaches a method of reinforcing or retrofitting building roof structures against hurricane force winds by applying a thin stream of a liquid polymer foam adhesive under pressure upwardly along the intersections of the rafters or support members and the roof panels to provide a filleted connection.
  • the liquid polymer foam adhesive is only effective in corner regions formed at the intersections between said support members and interior surfaces of the roof panels.
  • the present invention provides a solution to the above and other problems by providing improved reinforcing and anchoring of a roof and side walls to a building structure, wherein a greater hold down force is applied to the roof and side walls to counter the uplift and horizontal forces generated by high winds.
  • a roof panel or outer wall panel comprising spaced apart beam members, and a sheathing attached to and spanning a space between adjacent beam members; and spraying and adhering a layer of a foamable polymer adhesive composition such as a polyurethane or polyisocyanurate adhesive composition, which foamable polymer adhesive composition is preferably present in the form of foamable liquid, onto substantially the entirety of the beam members and substantially the entirety of the inner side of the sheathing such that the layer on the sheathing and the beam members is preferably substantially continuous.
  • substantially continuous it is meant that there are substantially no breaks or spaces in the layer, across the area on which it is deposited.
  • a closed cell spray polyurethane or polyisocyanurate foam is applied at a uniform depth under a roof deck or side wall sheathing between the structural beams to provide additional bonding strength. This is different from filleted adhesive caulks in that it provides additional bonding strength and also significant insulation under the roof deck or side walls. This creates a conditioned attic or side wall space and seals soffit areas to deter the intrusion of wind driven rain. This also provides a significant energy savings.
  • This invention uses such improved roof and side wall panels to help secure the roof to the side walls and the side walls to the flooring, and stiffens the roof and side walls to distribute wind loads to the roof and side wall framing.
  • the present invention can be incorporated during initial construction of a structure, or may be retrofitted into existing structures.
  • FIG. 1 is a perspective view of a structural test panel comprising an array of five parallel 2′′ ⁇ 4′′ by 72′′ spruce-pine-fir dimensional lumber spaced on 24′′ centers. Then a 7/16′′ oriented strand board (OSB) sheet is attached by nails.
  • OSB oriented strand board
  • FIG. 2 is a side view of the structural test panel of FIG. 1
  • FIG. 3 is a side view of the structural test panel of FIG. 2 having a filleted application, 3′′ high, 5-6′′ wide of a polyurethane closed-cell spray foam.
  • FIG. 4 is a side view of the structural test panel of FIG. 2 having a full layer application, 3′′ thick of a polyurethane closed-cell spray foam.
  • FIG. 5 shows a prior art arrangement where attic baffles are used along a roof panel where fibrous insulation is placed between structural members and in contact with the attic baffle.
  • FIG. 6 shows a view of the inventive closed-cell spray foam with an attic baffle placed between structural members and the foam is in contact with the attic baffle.
  • the invention provides a method of securing a roof or an outer wall of a building against wind forces, which comprises:
  • the invention also provides a structural member for a roof or an outer wall of a building comprising:
  • the invention further provides a structural member comprising:
  • the invention still further provides a structural member comprising:
  • Roofs and side walls in residential and light commercial buildings comprise two main elements: beams such as wood, wood composite, metal or combinations thereof as framing and rafters, and a sheathing.
  • a sheathing is a layer of boards or of other wood or fiber materials applied to the outer studs, joist, and rafters of a building to strengthen the structure and serve as a base for an exterior weatherproof cladding.
  • Sheathing is typically plywood, oriented strand board (OSB) fibrous cement, fiberglass reinforced gypsum, insulated sheathings, such as expanded and extruded polystyrene, or polyisocyanurate, but can also be foam board and combinations of these materials.
  • OSB oriented strand board
  • Beams are typically dimensional lumber made from softwood species of wood, engineered woods or formed steel. These have nominal cross sections of 2′′ ⁇ 3′′, 2′′ ⁇ 4′′, 2′′ ⁇ 6′′, 2′′ ⁇ 8′′, 2′′ ⁇ 10′′ or 2′′ ⁇ 12′′. These beams can be built as prefabricated truss assemblies or site-built as rafters or side framing. Sloped residential roofs and side walls are constructed by spacing the beams at regular intervals, typically 12′′, 16′′ or 24′′, most commonly 24′′. Sheathing is typically available in 4 ft. ⁇ 8 ft. sheets and is placed and fastened to a face of the beam with such fasteners as nails, screws or clips. Application of these fasteners is not always done properly in both new and existing homes, and can be a main cause of roof or side wall failure. roofing materials, including underlayment and shingles are then attached to the outside surface of the sheathing.
  • a uniform thickness of a closed cell spray polyurethane or polyisocyanurate foam adhesive insulation is then applied on the underside of the roof deck or side wall sheathing and maintains a continuous contact with at least a portion of the two opposite sides of the sides of the beams, preferably at least half of the width of the two opposite sides of the sides of the beams, and more preferably substantially the entirety of the two opposite sides of the beams which are perpendicular to the sheathing.
  • the closed cell spray polyurethane or polyisocyanurate foam adhesive because of its inherent strength and stiffness, and its ability to form a tenacious bond to other construction materials such as wood and steel, acts as an adhesive.
  • the closed cell spray polyurethane or polyisocyanurate foam adhesive acts to uniformly distribute the wind load from the sheathing to the beams, thus increasing the uplift load considerably. Testing has shown that typical uplift loads increase from approximately 70 pounds per square foot to approximately 240-285 pounds per square foot after the application of about 3′′ thickness of a closed cell spray polyurethane or polyisocyanurate foam adhesive. Considering that roofs of homes in coastal hurricane areas can be subjected to wind uplift loads of from about 100 to about 130 psf, this increase is significant. In addition to providing uplift resistance, an application of about 3′′ thickness of a closed cell spray polyurethane or polyisocyanurate foam adhesive can provide additional insulation, on the order of R19.
  • closed cell spray polyurethane or polyisocyanurate foam adhesive is water resistant, it can also be used to strengthen soffit areas against wind damage and prevent intrusion of wind driven rain in these areas. Closed cell spray polyurethane or polyisocyanurate foam adhesive may also provide a measure of corrosion protection to mechanical fasteners and brackets in roof structures.
  • Closed cell spray polyurethane or polyisocyanurate foam adhesives are well known in the art and are generally commercially available.
  • polyurethane or polyisocyanurate foams are prepared by combining an isocyanate, a polyol or mixture of polyols, a blowing agent or mixture of blowing agents, and other materials such as catalysts, surfactants, and optionally, flame retardants, colorants, or other additives.
  • Methods of producing polyurethane and polyisocyanurate foams are generally known and consist in general of the reaction of an organic polyisocyanate (including diisocyanate) and a polyol or mixture of polyols in the presence of a volatile blowing agent, which is caused to vaporize by the heat liberated during the reaction of isocyanate and polyol.
  • This reaction can be enhanced through the use of amine and/or other catalysts as well as surfactants.
  • the catalysts ensure adequate curing of the foam, while the surfactants regulate and control cell size. Flame-retardants are traditionally added to rigid polyurethane or polyisocyanurate foam to reduce its flammability.
  • Fluorocarbons act not only as blowing agents by virtue of their volatility, but also are encapsulated or entrained in the closed cell structure of the rigid foam and are the major contributor to the low thermal conductivity properties of rigid polyurethane foams.
  • the use of a fluorocarbon as the preferred commercial expansion or blowing agent in insulating foam applications is based in part on the reduced thermal conductivity, or k-factor associated with the foam produced.
  • K-factor is defined as the rate of transfer of heat energy by conduction through one square foot of one inch thick homogenous material in one hour where there is a difference of one degree Fahrenheit perpendicularly across the two surfaces of the material.
  • the isocyanate or polyisocyanate composition comprises the first component, commonly referred to as the “A” component.
  • the polyol or polyol mixture, surfactant, catalysts, blowing agents, flame retardant, and other isocyanate reactive components comprise the second component, commonly referred to as the “B” component.
  • foams are readily prepared by bringing together the A and B side components for spray applied foams, froths, and the like.
  • other ingredients such as fire retardant, colorants, auxiliary blowing agents, water, and even other polyols can be added as a third stream to the mix head or reaction site. Most conveniently, however, they are all incorporated into one B component.
  • the foam is a preferably applied at a thickness of from about 2.5 cm to about 15 cm.
  • the foam may be applied as single or multiple layers.
  • Any organic polyisocyanate can be employed in polyurethane or polyisocyanurate foam synthesis inclusive of aliphatic and aromatic polyisocyanates.
  • Preferred, as a class is the aromatic polyisocyanates.
  • Preferred polyisocyanates for rigid polyurethane or polyisocyanurate foam synthesis are the polymethylene polyphenyl isocyanates, particularly the mixtures containing from about 30 to about 85 percent by weight of methylenebis(phenyl isocyanate) with the remainder of the mixture comprising the polymethylene polyphenyl polyisocyanates of functionality higher than 2.
  • Preferred polyisocyanates for flexible polyurethane foam synthesis are toluene diisocyanates including, without limitation, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, and mixtures thereof.
  • Typical polyols used in the manufacture of rigid polyurethane foams include, but are not limited to, aromatic amino-based polyether polyols such as those based on mixtures of 2,4- and 2,6-toluenediamine condensed with ethylene oxide and/or propylene oxide.
  • aromatic alkylamino-based polyether polyols such as those based on ethoxylated and/or propoxylated aminoethylated nonylphenol derivatives. These polyols are generally preferred in spray applied polyurethane foams.
  • sucrose-based polyols such as those based on sucrose derivatives and/or mixtures of sucrose and glycerine derivatives condensed with ethylene oxide and/or propylene oxide.
  • Typical polyols used in the manufacture of flexible polyurethane foams include, but are not limited to, those based on glycerol, ethylene glycol, trimethylolpropane, ethylene diamine, pentaerythritol, and the like condensed with ethylene oxide, propylene oxide, butylene oxide, and the like. These are generally referred to as “polyether polyols”.
  • polyether polyols Another example is the graft copolymer polyols, which include, but are not limited to, conventional polyether polyols with vinyl polymer grafted to the polyether polyol chain.
  • polyurea modified polyols which consist of conventional polyether polyols with polyurea particles dispersed in the polyol.
  • polyols used in polyurethane modified polyisocyanurate foams include, but are not limited to, aromatic polyester polyols such as those based on complex mixtures of phthalate-type or terephthalate-type esters formed from polyols such as ethylene glycol, diethylene glycol, or propylene glycol. These polyols may be blended with other types of polyols such as sucrose-based polyols, and used in polyurethane foam applications.
  • Catalysts used in the manufacture of polyurethane foams are typically tertiary amines including, but not limited to, N-alkylmorpholines, N-alkylalkanolamines, N,N-dialkylcyclohexylamines, and alkylamines where the alkyl groups are methyl, ethyl, propyl, butyl and the like and isomeric forms thereof, as well as heterocyclic amines.
  • Typical, but not limiting, examples are triethylenediamine, tetramethylethylenediamine, bis(2-dimethylaminoethyl)ether, triethylamine, tripropylamine, tributylamine, triamylamine, pyridine, quinoline, dimethylpiperazine, piperazine, N,N-dimethylcyclohexylamine, N-ethylmorpholine, 2-methylpiperazine, N,N-dimethylethanolamine, tetramethylpropanediamine, methyltriethylenediamine, and mixtures thereof.
  • non-amine polyurethane catalysts are used.
  • Typical of such catalysts are organometallic compounds of lead, tin, titanium, antimony, cobalt, aluminum, mercury, zinc, nickel, copper, manganese, zirconium, and mixtures thereof.
  • Exemplary catalysts include, without limitation, lead 2-ethylhexoate, lead benzoate, ferric chloride, antimony trichloride, and antimony glycolate.
  • a preferred organo-tin class includes the stannous salts of carboxylic acids such as stannous octoate, stannous 2-ethylhexoate, stannous laurate, and the like, as well as dialkyl tin salts of carboxylic acids such as dibutyl tin diacetate, dibutyl tin dilaurate, dioctyl tin diacetate, and the like.
  • trimerization catalysts are used for the purpose of converting the blends in conjunction with excess A component to polyisocyanurate-polyurethane foams.
  • the trimerization catalysts employed can be any catalyst known to one skilled in the art including, but not limited to, glycine salts and tertiary amine trimerization catalysts, alkali metal carboxylic acid salts, and mixtures thereof.
  • Preferred species within the classes are potassium acetate, potassium octoate, and N-(2-hydroxy-5-nonylphenol)methyl-N-methylglycinate.
  • Dispersing agents may be incorporated into the blowing agent mixture.
  • Surfactants better known as silicone oils, are added to serve as cell stabilizers.
  • Some representative materials are sold under the names of DC-193, B-8404, and L-5340 which are, generally, polysiloxane polyoxyalkylene block copolymers such as those disclosed in U.S. Pat. Nos. 2,834,748, 2,917,480, and 2,846,458.
  • blowing agent mixture may include flame retardants such as tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(2,3-dibromopropyl) phosphate, tris(1,3-dichloropropyl) phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminum trihydrate, polyvinyl chloride, and the like.
  • flame retardants such as tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(2,3-dibromopropyl) phosphate, tris(1,3-dichloropropyl) phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminum trihydrate, polyvinyl chloride, and the like.
  • Other optional ingredients may include from 0 to about 5 percent of water based on the weight of the polyol blend, which chemical
  • blowing agents are also included in the mixture.
  • the amount of blowing agent present in the blended mixture is dictated by the desired foam densities of the final polyurethane or polyisocyanurate foams products.
  • the polyurethane foams produced can vary in density from about 1.0 to about 6.0 pounds per cubic foot, more preferably from about 1.8 to about 4.0 pounds per cubic foot and most preferably 2 to 4 pound per cubic foot.
  • the density obtained is a function of how much of the blowing agent, or blowing agent mixture, is present in the A and/or B components, or that is added at the time the foam is prepared.
  • the A-side chemicals e.g. polyisocyanate
  • B-side chemicals are mixed in appropriate amounts, typically equal amounts by volume, and then atomized into a mist.
  • the B-side contains polyols, the blowing agents, catalysts, fire retardants, etc.
  • the blowing agent is in a liquid form in solution in the B-side.
  • the water mixes with the polyisocyanate to form CO 2 gas, it creates gas cells in the polyurethane.
  • the component parts are mixed in the spray gun.
  • the polyurethane is created as the two chemicals mix and hits the wall or roof surface.
  • Useful blowing agents non-exclusively include: hydrocarbons, methyl formate, halogen containing compounds, especially fluorine containing compounds and chlorine containing compounds such as halocarbons, fluorocarbons, chlorocarbons, fluorochlorocarbons, halogenated hydrocarbons such as hydrofluorocarbons, hydrochlorocarbons, hydrofluorochlorocarbons, hydrofluoroolefins, hydrochlorofluoroolefins, CO 2 generating materials such as water, and organic acids that produce CO 2 such as formic acid.
  • Examples non-exclusively include low-boiling, aliphatic hydrocarbons such as ethane, propane and butane, normal pentane, isopentane and cyclopentane; ethers and halogenated ethers; trans 1,2-dichloroethylene, pentafluorobutane; pentafluoropropane; hexafluoropropane; and heptafluoropropane; 1-chloro-1,2,2,2-tetrafluoroethane (HCFC-124); and 1,1-dichloro-1-fluoroethane (HCFC-141b) as well as 1,1,2,2-tetrafluoroethane (HFC-134); 1,1,1,2-tetrafluoroethane (HFC-134a); 1-chloro 1,1-difluoroethane (HCFC-142b); 1,1,1,3,3-pentafluorobutane (HFC-365mfc); 1,1,1,
  • blowing agent is 1,1,1,3,3-pentafluoropropane (HFC-245fa) which is commercially available from Honeywell International Inc. as Enovate Blowing Agent. This latter molecule remains in solution until the heat generated by the polyurethane and/or the polyisocyanurate reaction vaporizes it and creates the gas in the cells of the polyurethane foam.
  • HFC-245fa 1,1,1,3,3-pentafluoropropane
  • the mixture comprises only one blowing agent.
  • the mixture comprises a plurality of blowing agents, for example a combination of two blowing agents or combinations of three blowing agents.
  • each individual blowing agent may be present in an amount of from about 1 percent by weight to about 99 percent by weight, wherein the total amount of blowing agent is 100% by weight.
  • one blowing agent may be present in an amount of from about 1 percent by weight to about 50 percent by weight and the other blowing agent may be present in an amount of from about 50 percent by weight top about 99 percent by weight.
  • blowing agents comprises 1,1,1,3,3-pentafluorobutane and at least one fluorinated hydrocarbon selected from the group consisting of 1,1,1,2-tetrafluoroethane, 1,1,1,3,3-pentafluoropropane, 1,1,1,3,3,3-hexafluoropropane and 1,1,1,2,3,3,3-heptafluoropropane.
  • a particularly useful combination of blowing agents comprises from about 50% to about 99% by weight of 1,1,1,3,3-pentafluorobutane and from about 1% to 50% by weight of at least one fluorinated hydrocarbon selected from the group consisting of 1,1,1,2-tetrafluoroethane, 1,1,1,3,3-pentafluoropropane, 1,1,1,3,3,3-hexafluoropropane and 1,1,1,2,3,3,3-heptafluoropropane.
  • blowing agents comprises a) pentafluorobutane, and b) at least one further blowing agent selected from the group consisting of low-boiling, aliphatic hydrocarbons selected from the group consisting of ethane, propane and butane, normal pentane, isopentane, or cyclopentane; halogenated hydrocarbons; ethers and halogenated ethers; difluoromethane (HFC-32); difluoroethane; 1,1,2,2-tetrafluoroethane (HFC-134); 1,1,1,2-tetrafluoroethane (HFC-134a); pentafluoropropane; hexafluoropropane, and heptafluoropropane; particularly wherein the pentafluorobutane is 1,1,1,3,3-pentafluorobutane (HFC-365mfc), and the further blowing agent comprises at least one of 1,1-
  • blowing agents comprises 1,1,1,3,3-pentafluorobutane (HFC-365mfc) and 1,1,1,3,3-pentafluoropropane (HFC-245fa).
  • Useful amounts may range from up to about 50 weight percent of HFC-365mfc and about 50 weight percent or more of HFC-245fa.
  • blowing agents comprises 1,1,1,3,3-pentafluorobutane (HFC-365mfc) and 1,1,1,3,3-pentafluoropropane (HFC-245fa).
  • Useful amounts may have an HFC-365mfc to HFC-245fa weight ratio range of from 40:60 to about 80:20.
  • blowing agents comprises HFC-365mfc, HFC-227ea and one or both of HFC-245fa and HFC-134a.
  • Preferably 65 to 85 parts by weight comprises HFC-365mfc and HFC-227ea of which percentage, 80 to 95 parts by weight are HFC-365mfc, and the remainder is HFC-227ea; and at least 15 parts by weight comprises one or both of HFC-245fa and HFC-134a.
  • blowing agent compositions according to the invention may include other optional ingredients such as phosphorus compounds and catalysts.
  • a useful combination comprises from about 10 to about 20% by weight of a phosphorus compound, preferably triethyl phosphate or tris-chloroisopropyl phosphate; and a mixture of: a) HFC-365mfc, and b) HFC-134a, HFC-227ea or HFC-245fa.
  • a phosphorus compound preferably triethyl phosphate or tris-chloroisopropyl phosphate
  • a useful combination comprises HFC-365mfc and a catalyst which catalyses the polyol/isocyanate reaction and, optionally which catalyses the trimerization of isocyanates.
  • Closed-cell spray foams suitable for this application preferably have the following nominal properties:
  • Useful closed-cell spray foams include Comfort Foam® FE178, FE158, CF178, CF158 commercially available from BASF Polyurethanes—Foam Enterprises (a division of BASF) of Florham Park, N.J.; BaySealTM 2.0 commercially available from BaySystems (a division of Bayer) of Spring, Tex.; Corbond® commercially available from Corbond of Bozeman, Mont.; HeatLok Soy 0240 commercially available from Demilec USA of Arlington, Tex.; StyrofoamTM 2.0 commercially available from Dow Chemical Company of Midland, Mich.; PF-173, PF-193 commercially available from Gaco Western of Seattle, Wash.; Permax commercially available from Resin Technology Division (a division of Henry Co.) of Ontario, CA; Foam LokTM FL-2000TM commercially available from Lapolla Coatings of Houston, Tex.; InsulStar® commercially available from NCFI Polyurethanes (formerly North Carolina Foam Industries) of Mt. Airy, N.C.; and Dur
  • an elongated channel for the passage of ventilating air is fixed on the inner side of the sheathing between and separated from adjacent spaced apart beam members.
  • a layer of the rigid, closed cell foam polymer adhesive composition is positioned on the side walls of the beam members, on the elongated channel, and on the inner side of the sheathing between the elongated channel and the spaced apart beam members.
  • the layer of rigid, closed cell foam on the sheathing, the elongated channel and the beam members is substantially continuous, and adheres the sheathing to the beam members.
  • substantially continuous it is meant that there are substantially no breaks or spaces in the layer, across the area on which it is deposited.
  • FIG. 5 shows a prior art arrangement where fibrous insulation is then placed between the structural members and in direct contact with a double channel baffle.
  • FIG. 6 shows an arrangement according to the invention where an attic baffle is provided with a closed-cell spray foam to provide the requisite ventilation needed and provide adequate wind uplift resistance.
  • a typical double channel baffle as shown in FIG. 5 can be split into a single chute as shown in FIG. 6 , and installed along a central axis of the sheathing parallel to the structural members. This would allow sufficient contact area between stapling flanges of the single chute baffle and the structural members needed for the spray foam to adhere between the roof deck and the sidewall of the structural member.
  • This design can provide a 1:300 ventilation area as is required in almost all home designs.
  • closed-cell spray foam may trap water/moisture in the decking material in the event of a roof leak, which would be undetectable until after the roof sheathing sufficiently decayed.
  • attic baffles or vent chutes which are elongated channels, are commonly used to preserve a ventilation path between the roof deck and fibrous insulation placed on the attic floor.
  • a wide variety of these components are commercially available, including ones made from vacuum-formed XPS sheets, solid PS, and cardboard.
  • An example of an XPS attic vent is marketed by Owens Corning.
  • This Example details the test procedure to determine the ultimate wind uplift load for roof/wall panels reinforced with a closed-cell spray polyurethane foam. It is based on a slightly modified version of ASTM E330-02 “Standard Test Method for Structural Performance of Exterior Windows, Doors, Skylights and Curtain Walls by Uniform Static Air Pressure Difference” using a test wind uplift test arrangement.
  • a structural member is formed according to the configuration shown in FIG. 1 and FIG. 2 .
  • the structural test panel comprises an array of five parallel 2′′ ⁇ 4′′ by 72′′ spruce-pine-fir dimensional lumber beams spaced on 24′′ centers.
  • a 7/16′′ oriented strand board (OSB) sheet is fastened to the inside surface of the OSB by nails.
  • the fasteners used were 6d ringshank nails applied using a pneumatic nail gun. Spacing of the ringshank fasteners was 6′′ for the two framing members at each end. Spacing of the ringshank nail fasteners on the three inner framing members was on 12′′ centers.
  • Fillets of foam insulation were sprayed along the interface of the sheathing and the 2 ⁇ 4's. For the full layer application, 5 specimens are fully covered from truss to truss with a 3′′ thick layer of the foam insulation.
  • the polyurethane was InsulStar ccSPF polyurethane manufactured by NCFI Polyurethanes.
  • the test panels were stored for more than two weeks at a warehouse prior to the start of testing so that the foam is allowed to cure to achieve optimum bond strength.
  • the spray is pumped through separate lines from steel barrels. The chemicals are combined at the nozzle of the spray gun and dispersed under a pressure of 1,000 psi. The foam immediately increases in volume once it is applied to a surface.
  • the panel specimens were placed in an upside down position in a test frame.
  • the approximate dimensions of the top opening of the test frame are about 5 ft ⁇ 9 ft.
  • the OSB sheet When centered in the test frame the OSB sheet is suspended by the dimensional lumber, which spans across the 5 ft dimension of a test frame.
  • a polyethylene sheet is then draped carefully across the test panel, and cut so that it is just even with the bottom of the test frame. The polyethylene sheet is then sealed to the bottom of the test frame with duct tape.
  • a vacuum pump is turned on, and a vacuum valve is opened slightly to evacuate the test frame. This pulls the polyethylene sheet over the test panel. Care is taken to be sure the polyethylene sheet drapes evenly over the test panel without excessive folding to prevent risk of leakage. Any leaks that may develop are sealed with duct tape. After an initial removal of air, a vacuum is applied at an even, controlled rate. At pre-defined pressure increments, the panel is allowed to sit for approximately 15-30 seconds before the pressure is increased to the next increment.
  • Vacuum pressure is controlled and monitored on a digital gage until failure. Failure is readily noticeable, producing a distinctly visual and audible sound at failure. Failure typically occurs by a failure of the connection between the OSB and dimensional lumber. At the point of failure, the maximum pressure recorded by the digital pressure gage is then recorded. This pressure (vacuum) is then converted to pounds per square foot, and becomes the measured wind uplift load.

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Polyurethanes Or Polyureas (AREA)
  • Building Environments (AREA)
  • Laminated Bodies (AREA)
US12/107,161 2007-06-25 2008-04-22 Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam Abandoned US20080313985A1 (en)

Priority Applications (3)

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US12/107,161 US20080313985A1 (en) 2007-06-25 2008-04-22 Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam
PCT/US2008/067857 WO2009002910A2 (fr) 2007-06-25 2008-06-23 Procede destine a ameliorer la resistance a l'arrachement sous l'action du vent de toits a ossature de bois au moyen d'une mousse de polyurethane a alveoles fermees pulverisable
TW097123540A TW200914695A (en) 2007-06-25 2008-06-24 Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam

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US94597407P 2007-06-25 2007-06-25
US94826907P 2007-07-06 2007-07-06
US3657908P 2008-03-14 2008-03-14
US12/107,161 US20080313985A1 (en) 2007-06-25 2008-04-22 Method for increasing wind uplift resistance of wood-framed roofs using closed-cell spray polyurethane foam

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US20100102273A1 (en) * 2008-10-28 2010-04-29 Honeywell International Inc. Azeotrope-like compositions comprising trans-1-chloro-3,3,3-trifluoropropene
WO2010085397A1 (fr) * 2009-01-22 2010-07-29 Arkema Inc. Trans-1,2-dichloroéthylène dont le point éclair est augmenté par du 1-chloro-3,3,3-trifluoropropène
US20110124757A1 (en) * 2009-05-21 2011-05-26 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
WO2013016632A3 (fr) * 2011-07-28 2013-04-25 Honeywell International Inc. Mousses et articles ininflammables obtenus à partir de mousses contenant du 1-chloro-3,3,3-trifluoropropène (1233zd)
US20130118104A1 (en) * 2010-02-12 2013-05-16 Darek Shapiro Building module, a method for making same, and a method for using same to construct a building
US8474207B1 (en) * 2012-06-12 2013-07-02 John A Gilbert Strengthening wood frame construction against wind damage
GB2501885A (en) * 2012-05-08 2013-11-13 Stormking Plastics Ltd Dormer assembly comprising frame and cover with insulation
US8696966B2 (en) 2011-10-27 2014-04-15 Huntsman International Llc Method of fabricating a wall structure
US8703006B2 (en) 2008-10-28 2014-04-22 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US9150768B2 (en) 2008-10-28 2015-10-06 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US20160017127A1 (en) * 2014-07-18 2016-01-21 Johns Manville Spray foams containing non-halogenated fire retardants
US9267294B2 (en) 2013-03-15 2016-02-23 Darek Shapiro Bracket, a building module, a method for making the module, and a method for using the module to construct a building
US9919499B2 (en) * 2014-06-28 2018-03-20 Kenneth Robert Kreizinger Stiffened frame supported panel
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US20180266107A1 (en) * 2015-09-30 2018-09-20 Sebastian Martinez Method for producing a wall or roof module having installations included and walls or roofs prefabricated using said method
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US10301823B2 (en) * 2014-06-28 2019-05-28 Kenneth Robert Kreizinger Frame supported panel
US20190242127A1 (en) * 2014-06-28 2019-08-08 Kenneth R. Kreizinger Foam Backed Panel With Cantilever
US10563398B1 (en) * 2019-04-10 2020-02-18 Kenneth R. Kreizinger Method of stiffening a frame supported panel
US20200141119A1 (en) * 2017-10-18 2020-05-07 Kenneth R. Kreizinger Impact Resistance of a Cementitious Composite Foam Panel
US10870987B1 (en) 2017-12-04 2020-12-22 Firestone Building Products Company, Llc Isocyanate-based foam construction boards
US11174364B2 (en) 2015-12-08 2021-11-16 Firestone Building Products Company, Llc Process for producing isocyanate-based foam construction boards
WO2024040243A3 (fr) * 2022-08-19 2024-03-21 Owens Corning Intellectual Capital, Llc Système de revêtement multi-matériaux à isolation thermique améliorée
US11999833B2 (en) 2021-10-26 2024-06-04 Holcim Technology Ltd Process for producing isocyanate-based foam construction boards

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US7935268B2 (en) * 2008-10-28 2011-05-03 Honeywell International Inc. Azeotrope-like compositions comprising trans-1-chloro-3,3,3-trifluoropropene
US9175200B2 (en) 2008-10-28 2015-11-03 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US8163196B2 (en) 2008-10-28 2012-04-24 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US9150768B2 (en) 2008-10-28 2015-10-06 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US20100102272A1 (en) * 2008-10-28 2010-04-29 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US9926244B2 (en) 2008-10-28 2018-03-27 Honeywell International Inc. Process for drying HCFO-1233zd
US8703006B2 (en) 2008-10-28 2014-04-22 Honeywell International Inc. Azeotrope-like compositions comprising 1-chloro-3,3,3-trifluoropropene
US20100102273A1 (en) * 2008-10-28 2010-04-29 Honeywell International Inc. Azeotrope-like compositions comprising trans-1-chloro-3,3,3-trifluoropropene
WO2010085397A1 (fr) * 2009-01-22 2010-07-29 Arkema Inc. Trans-1,2-dichloroéthylène dont le point éclair est augmenté par du 1-chloro-3,3,3-trifluoropropène
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EP2379779A4 (fr) * 2009-01-22 2016-07-13 Arkema Inc Trans-1,2-dichloroéthylène dont le point éclair est augmenté par du 1-chloro-3,3,3-trifluoropropène
US20110124757A1 (en) * 2009-05-21 2011-05-26 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
US8541478B2 (en) 2009-05-21 2013-09-24 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
US8481605B2 (en) 2009-05-21 2013-07-09 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
US8937107B2 (en) 2009-05-21 2015-01-20 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
US9527976B2 (en) 2009-05-21 2016-12-27 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
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US9587080B2 (en) 2009-05-21 2017-03-07 Huntsman International Llc Rigid polyurethane foam and system and method for making the same
US20130118104A1 (en) * 2010-02-12 2013-05-16 Darek Shapiro Building module, a method for making same, and a method for using same to construct a building
US9068350B2 (en) * 2010-02-12 2015-06-30 Darek Shapiro Building module, a method for making same, and a method for using same to construct a building
WO2013016632A3 (fr) * 2011-07-28 2013-04-25 Honeywell International Inc. Mousses et articles ininflammables obtenus à partir de mousses contenant du 1-chloro-3,3,3-trifluoropropène (1233zd)
US20140220333A1 (en) * 2011-07-28 2014-08-07 Honeywell International Inc. Foams and flame resistant articles made from foams containing 1-chloro-3,3,3-trifluoropropene (1233zd)
US9255400B2 (en) 2011-10-27 2016-02-09 Huntsman International Llc Polyurethane foam wall structure
US8696966B2 (en) 2011-10-27 2014-04-15 Huntsman International Llc Method of fabricating a wall structure
GB2501885A (en) * 2012-05-08 2013-11-13 Stormking Plastics Ltd Dormer assembly comprising frame and cover with insulation
US8474207B1 (en) * 2012-06-12 2013-07-02 John A Gilbert Strengthening wood frame construction against wind damage
US9267294B2 (en) 2013-03-15 2016-02-23 Darek Shapiro Bracket, a building module, a method for making the module, and a method for using the module to construct a building
US9765515B2 (en) 2013-03-15 2017-09-19 Darek Shapiro Bracket, a building module, a method for making the module, and a method for using the module to construct a building
US9919499B2 (en) * 2014-06-28 2018-03-20 Kenneth Robert Kreizinger Stiffened frame supported panel
US10865562B2 (en) * 2014-06-28 2020-12-15 Kenneth R. Kreizinger Foam backed panel with cantilever
US10301823B2 (en) * 2014-06-28 2019-05-28 Kenneth Robert Kreizinger Frame supported panel
US20190242127A1 (en) * 2014-06-28 2019-08-08 Kenneth R. Kreizinger Foam Backed Panel With Cantilever
US9815966B2 (en) * 2014-07-18 2017-11-14 Johns Manville Spray foams containing non-halogenated fire retardants
US20160017127A1 (en) * 2014-07-18 2016-01-21 Johns Manville Spray foams containing non-halogenated fire retardants
US20180266107A1 (en) * 2015-09-30 2018-09-20 Sebastian Martinez Method for producing a wall or roof module having installations included and walls or roofs prefabricated using said method
US11174364B2 (en) 2015-12-08 2021-11-16 Firestone Building Products Company, Llc Process for producing isocyanate-based foam construction boards
CN109476115A (zh) * 2016-04-28 2019-03-15 自然工作有限责任公司 具有聚丙交酯树脂饰面层的聚合物泡沫隔热结构
US20190126596A1 (en) * 2016-04-28 2019-05-02 Natureworks Llc Polymer foam insulation structures having a facing layer of a polylactide resin
US10227779B2 (en) 2016-10-06 2019-03-12 Covestro Llc Methods for making pre-fabricated insulated wall structures and apparatus for use in such methods
US10294668B2 (en) 2017-01-04 2019-05-21 Kenneth R. Kreizinger Stiffened foam backed composite framed structure
US20200141119A1 (en) * 2017-10-18 2020-05-07 Kenneth R. Kreizinger Impact Resistance of a Cementitious Composite Foam Panel
US10961709B2 (en) * 2017-10-18 2021-03-30 Kenneth R. Kreizinger Impact resistance of a cementitious composite foam panel
US10870987B1 (en) 2017-12-04 2020-12-22 Firestone Building Products Company, Llc Isocyanate-based foam construction boards
US10563398B1 (en) * 2019-04-10 2020-02-18 Kenneth R. Kreizinger Method of stiffening a frame supported panel
US11999833B2 (en) 2021-10-26 2024-06-04 Holcim Technology Ltd Process for producing isocyanate-based foam construction boards
US12006414B2 (en) 2021-11-08 2024-06-11 Holcim Technology Ltd Process for producing isocyanate-based foam construction boards
WO2024040243A3 (fr) * 2022-08-19 2024-03-21 Owens Corning Intellectual Capital, Llc Système de revêtement multi-matériaux à isolation thermique améliorée

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