US2074497A

US2074497A - Structural assembly

Info

Publication number: US2074497A
Application number: US13819A
Authority: US
Inventors: Paul A Voigt
Original assignee: Johns Manville
Current assignee: Johns Manville Corp; Johns Manville
Priority date: 1935-03-30
Filing date: 1935-03-30
Publication date: 1937-03-23
Anticipated expiration: 1954-03-23

Description

March 23,1937. P A. 90m 2,074,497

STRUCTURAL ASSEMBLY Filed March 50, 1955 INVENTOR. Paul A. Voigt.

ATTORNEK BY aha $52 M! Patented Mar. 23, 1937 PATENT OFFICE STRUCTURAL ASSEMBLY Paul A. Voigt, Woodhaven, N. Y., assignor to Johns-Manville Corporation, New York, N. Y., a corporation of New York Application March 30, 1935, Serial No. 13,819 10 Claims. (01. 108-33) This invention relates to a structural assembly and particularly to a roof comprising a supporting substructure, corrugated sheets overlapping at their side portions to form a lapped joint, and

concavo-convex reenforcing strips disposed between the lapped portions of the said sheets and secured at both ends to the substructure.

Great pains have been taken and expense incurred, by the manufacturers of corrugated sheets of asbestos and Portland cement or the like to eliminate hazard to the constructor in assembling such sheets in a roof. Thus, the sheets of corrugated roofing material have been made oversize in thickness, to provide an additional safety factor, and directions issued that a man standing upon the sheets during the installation must usea load-distributing member, such as a heavy board with cleats on the upper side thereof, for supporting himself at all times.

In spite of these precautions, there are unfortunate instances of breakage of the sheets under conditions of abuse during installation.

The present invention comprises means of reducing the danger of breakage of sheets of corrugated asbestos cement board or the like during installation or of reducing the danger of serious injury to a workman upon the roof at the time of breakage. The invention comprises also means of flashing the joint between overlapping sheets of building material. Other objects and advantages comprised within the invention will be evident from the description that follows.

A preferred embodiment of the invention will be described in connection with the drawing, in

which Fig. 1 shows a perspective view of a portion of my improved roof partly broken away for clearness of illustration;

Fig. 2 shows a sectional view at the joint portion between adjacent sheets in direction transverse to the length of the strip; and

Fig. 3 shows a cross sectional view of a form of flashing strip that is preferred at this time.

There are shown spaced, approximately parallel beams l and I, suitably flanged beams such as channel irons, constituting a part of the supporting substructure above which are placed sheets 2 of roofing material.

A suitable type of sheet for the present purpose is one made by forming a wet mixture of asbestos fibres and Portland cement, shaping and strongly compressing the composition into a corrugated sheet, with attendant elimination of excess water, and then allowing the cement in the shaped composition to harden.

The sheets of roofing material overlap at their side portions to define therebetween lapped joints 3 extending parallel to the length of the corrugations, as illustrated.

Disposed between the lapped portions, that is, within the joints and extending therealong, are the reenforcing and flashing strips 4 of convex upper surface and concave lower surface. These strips are secured at both ends to the supporting substructure, as, for example, by means including bolts 5, extending through properly spaced holes in the strips and having heads 6, suitably saddleshaped, engaged above the said holes. The bolts are secured to the substructure, asby J-clips I and 8.

Each of the sheets and reenforcing strips bridge the space between two or more of the said beams and are supported thereover.

If the bolt were secured only to the lower flange of the channel iron support by the clip I, the reenforcing strip, under heavy loading, might become disengaged from the substructure, as by being bent'in the middle and slipped at its ends away from the channel iron beams. To avoid this possibility, the clips 8 secure the bolts and, therefore, the reenforcing strips to the substructure at a position adjacent to the roofing material that is the lower sheet at the joint. With such attachment to the uppermost portion of the substructure, loading the sheet 2 at a position between adjacent beams does not cause disengagement but actually increases thetightness of the engagement to beams I or I.

To promote proper flashing, close the joint against entrance of air or moisture, and to minimize transmission of vibrations or shock from one sheet to the adjacent overlapping sheet, the strips 4 advantageously include layers 9 and ll) of vibration-damping flashing material applied, respectively, to the convex and concave faces of the metal member constituting the core of the finished reenforcing and flashing strip. The elements 9 and [0 may be of any suitable material resistant to moisture and air, such as a heavy coating of asphalt or, preferably, strips of the type of asphalt-impregnated rag felt. They should be inelastic and yieldable.

Preferably, the strips of felt or the like applied to opposite faces of the metal reenforcing strips extend laterally beyond the side edges of the metal and are adhered to each other, as at positions I3 and M, Fig. 3, to provide a seal extending over the edges of the metal and protecting it from the atmosphere.

To provide for minor and accidental irregularities that may exist in the surfaces being flashed, there may be applied to the side edges of the reenforcing and flashing strip a layer ll, say of bulb-shaped cross section, of weatherresistant deformable material such as asphalt, the thickness of the layer being greater than the thickness of the reenforcing strip in the central portion thereof. When the assembly is made, this plastic deformable material closes the space between adjacent sheets and is caused to conform to minor irregularities of surface thereof.

. and minimize the tendency to breakage or leakage.

It will be noted that the fastening means, including the bolt 5, do not extend through the sheet that is uppermost (or outermost) at a joint portion. On the other hand, this sheet at the said joint portion is secured to the lower (or inner) sheet by means such as bolts l2, extending loosely through the upper sheet, as, for ex- I ample, through an oversize hole therein, and en- I "the lower of the sheets, at the joint portion,

' I gaging the lower sheet tightly.

Thus, aself-tapping (self-threadingl bolt, preferably, with a head ofnon-corrodible exterior, as of lead or the like, is'inserted at its stem portion through an oversize hole in the upper sheet'and then threaded into the lower sheet. In this manner, the hole through the lower sheet is no larger than the tapping portion of the bolt, and there is a tight non-leaking engagement between the stem of the bolt and. the lower sheet. At the same time, the looseness of fit of the bolt in the hole of the uppersheet makes possible limited lateral movement of one sheetwith respect to the other and, thereby, eliminates strains that would otherwise be set up by such factors as expansion with change in temperature or change in moisture content of the sheets.

It will be noted, also, that the bolts l2 engage on the side of acorrugation remote from the side edge of. the lower sheet, so that the slope of the lower sheet at the locality of the engagement is away from the side edge of the lower sheet, thus promoting drainage, away from the said edge, of water that may pass through the oversize hole in the overlying sheet.

The roof constructed as described contains essentially a metal skeleton including beams and reenforcing strips extending transversely with respect to each other. It will be noted also that the reenforcing strips are disposed at theside portions of 'the sheets of roofing material, this being the position of greatest danger of breaking during assembly.

Furthermore, the reenforcing strips are concealed from view from a position either above or below the roof, the exposure, if any, being limited to the relatively inconspicuous ends of the strips.

When the construction of the type described is used for a vertical wall of a building, the strips rection parallel to the length of the corrugations,

and springy concavo-convex reenforcing and flashing strips extending continuously between the overlapping portions of adjacent sheets, the curvature of the said strips being normally greater than the curvature of the overlapping portions of the sheets, whereby resilient close contact between the side edges of the reenforcing and flashing strips and the said overlapping portions is obtained. I

2. A roof including supported sheets of roofing material overlapping at their edges to form joints between adjacent sheets and springy reenforcing, and flashing strips, of cross section normally non-conforming to the said adjacent portions, disposed in the joint, extending continuously therein, and providing springy flashing therefor.

3. An assembly including a substructure, corrugated sheets supported thereupon and overlapping at their side portions to form lapped joints extending between adjacent sheets, in direction parallel to the length of the corrugations, springy concave-convex reenforcing and flashing strips disposed between the overlapping portions of adjacent sheets and extending continuously in thejoint therebetween, and vibration-damping material of the type of felt applied over opposite faces of the said strips.

4. An assembly including a substructure, corrugated sheets supported thereupon and overlapping at their side portions to form; lapped joints extending between adjacent sheets, in direction parallel to the length ofthe corrugations,

springy concave-convex reenforcing and flashing strips disposed between the overlapping portionsof adjacent sheets and extending continuously in the-joint therebetween, and de- -'formable weather-resistant plastic material of extending between adjacent sheets, in direction parallel to the length of the corrugations, and

fastening members of the type of self-tapping bolts extending through the lapped portions of the sheets that are outermost at the joints and engaging in tight non-leaking manner the lapped portions of the inner sheets.

6. A structural assembly including supported corrugated sheets of building material overlapping, at their side portions to form lapped joints extending between adjacent sheets, in direction parallel to the length of the corrugations, and fastening members of the type of self-tapping bolts extending loosely through the lapped portions of the sheets that are outermost at the joints and engaging in tight non-leaking mantier the lapped portions of the inner sheets, whereby lateral movement of the lapped portions of adjacent sheets with respect to each other is promoted and a non-leaking joint is provided.

7. A structural assembly including supported corrugated sheets of building material overlapping at their side portions to form lapped joints extending between adjacent sheets, in direction parallel to the length of the corrugations, and fastening members of the type of self-tapping bolts extending loosely through the lapped portions of the sheets that are outermost at the joints and engaging in tight non-leaking manner, the lapped portions of the inner sheets at positions on the sides of ,corrugations remote from the edges of the said inner sheets, whereby drainage in the localities of the fastening means is caused to be in direction away from the edges of the inner sheets.

8. A root including a supporting substructure comprising spaced approximately parallel beams, sheets of mating material placed thereabove, bridging each a space between two of the said beams, and overlapping at their side portions to form lapped joints between adjacent sheets, reenforcing strips disposed within the said joints and bridging e ch 9. space between two of the said beams, and means securing the reenforcing strips at both of their ends to the said beams.

9. A roof including a supporting substructure comprising spaced approximately parallel beams, sheets of roofing material placed thereabove, bridging each a space between two of the said beams, and overlapping at their side portions to form lapped joints between adjacent sheets, reenforcing strips of convex upper surface and concave lower surface disposed within the said Joints and bridging each a space between two of the said beams, and means se-, curing the reenforcing strips at both of their ends to the uppermost part of the said beams, whereby displacement of the endsof the strips with respect to the said uppermost part of the beams is prevented.-

10. A reenforcing and vibration-damping member adapted for use as one of the flashing strips in the'assembly described in claim 6, the said member comprising a narrow metal strip of concave-convex cross section and yieldable vibration-damping and flashing material applied to opposite races thereof.

PAUL A. 'VOIGT.