US3466832A

US3466832A - Structural assembly for use in a building

Info

Publication number: US3466832A
Application number: US563122A
Authority: US
Inventors: Adrian Anthony Cecil March
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-07-07
Filing date: 1966-07-06
Publication date: 1969-09-16
Anticipated expiration: 1986-09-16
Also published as: NL6609563A; DK113466B; DE1708963A1; BE683703A; CH458689A; GB1157084A; SE331743B

Description

Sept. 16, 1969 A. A. c. MARCH STRUCTURAL ASSEMBLY FOR USE IN A BUILDING 8 Sheets-Sheet 1 Filed July 6, 1966 Sept. 16, 1969 A. A. C. MARCH STRUCTURAL ASSEMBLY FOR USE IN A BUILDING Filed July 6. 1966 8 Sheets-Sheet 2 Sept. 16, 1969 A. A. c. MARCH STRUCTURAL ASSEMBLY FOR USE IN A BUILDING 8 Sheets-Sheet Filed July 6. 1966 IIIIIIIIIIII p 1969 A. A. c. MARCH 3,466,832

STRUCTURAL ASSEMBLY FOR USE IN A BUILDING Filed July 6. 1966 8 Sheets-Sheet 4.

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STRUCTURAL ASSEMBLY FOR USE IN A BUILDING Filed July 6, 1966 a Sheets-Sheet 6 Sept. 16, 1969 A. A. c. MARCH STRUCTURAL ASSEMBLY FOR USE IN A BUILDING 8 Sheets-Sheet '7 Filed July 6. 1966 www |1||||| l l 4 I I I l i I:

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STRUCTURAL ASSEMBLY FOR USE IN A BUILDING Filed July 6, 1966 8 Sheets-Sheet E- United States Patent 3,466,332 STRUCTURAL ASSEMBLY FOR USE IN A BUILDING Adrian Anthony Cecil March, Oaklea, Hartfield, Sussex, England Filed July 6, 1966, Ser. No. 563,122 Claims priority, application Great Britain, July 7, 1965,

Int. Cl. E0411 1/06; E04c 1/30,

US. Cl. 52-536 17 Claims ABSTRACT OF THE DISCLOSURE A structural member particularly for building a roof having a downwardly facing receiving component along at least one edge for engagement with a complementary upwardly extending entering component of an adjacent member, assembly being effected by a rotary movement to bring the components of the adjacent members into a locked condition in which transverse movement in any direction is prevented by contact between the said components, the joint formed thereby including a Ire-entrant extremity, an upwardly inclined surface on the receiving component, and a contact surface in said receiving component opposed to said re-entrant extremity. A second extremity may be provided which extends downwardly and provides an edge off which rainwater will drip. The structural member may have a receiving component at each edge or the other edge may have an entering component.

It is characteristic of most roofing systems that the weather resistant member is small in relation to the span, and possesses no great mechanical strength requiring a supporting structure which may account for a substantial proportion of the weight and cost of a completed roof.

An obvious improvement is to use a weather resistant member of appropriate proportions and material to span the required distance without additional support. Such a member, if it is to be handled easily and manufactured economically, is likely to be relatively narrow in relation to its length and will require (like tongued and grooved floorboards) to be joined to adjacent members in such a way as to prevent relative vertical movement, not only for weatherproofing reasons but so that load applied to one member can be shared by adjacent members. In addition roof members have to remain weatherproof, without complications being introduced in manufacture and erection.

One of the objects of the present invention is to provide a roofing system consisting of members adapted to span substantial distances without intermediate support and to be engaged with each other or with a jointing element at adjacent edges to form a weatherproof joint capable of transmitting mechanical load. Such members may be produced by a variety of processes, and illustrations given in the accompanying drawings both of members formed from sheet, as for example by vacuum forming a thermoplastic sheet material and the similar case of a glass reinforced resin laminate, and of members formed by extrusion either of metal or plastic. Other processes and techniques may obviously be used, and for certain application may have advantages.

According to the present invention I provide a structural member for use in building, said member having an outer and inner face and including marginal engagement portions at opposite edges of the structural member for interengagement with other members having complementary engagement portions in edge to edge alignment "ice and a mounting portion distinct from said engagement portions and accessible from the inner face, one said engagement portion having inner and outer elements of which the outer element is the one on the outer face of said member said outer element including an abutment feature extending towards the inner element, the male portion of an adjacent member being engageable in said female portion between the abutment feature and the inner element and turnable about said abutment feature towards an aligned position of the members said rotation increasing the entry of the male margin into the female engagement portion said adjacent members when aligned being locked together against relative lateral displacement.

According to a further embodiment there is provided a structural member for use in building said member having an outer and inner face and including marginal male and female engagement portions at opposite edges of the structural member for interengagement with other members in edge to edge alignment and a mounting portion distinct from said male or female engagement portions and accessible from the inner face, said female portion having irmer and outer elements of which the outer element is the one on the outer face of said member said outer element including an abutment feature extending towards the inner element, the male portion of the adjacent member being engageable in the female portion between the abutment feature and the inner element and turnable about said abutment feature towards an aligned position of the members said rotation increasing the entry of the male margin into the female engagement portion said adjacent members when aligned being locked together against relative lateral displacement.

The mounting portion means that part of the member adapted to be engaged by securing means and the term distinct as applied to the mounting portion means that if the mounting portion were removed the geometry of the joint is not changed. Sealing means may be provided along at least one margin of said member adapted to form a weather-sealed joint with an adjacent member or an additional member. A weather-sealed joint is one that is capable of resisting the passage of surface water and/ or rain and/ or wind through the joint.

According to a further feature of the invention the joint has at least two lines of contact one higher than and shielded from the weather by the other whereof the lower one is the more exposed so that moisture does not go downhill to reach the second.

The member may be secured at at least one end to a support in such a manner that the support assists in resisting bending of said member.

Referring to the accompanying drawings:

FIG. 1 is a diagrammatic isometric view of a portion of roof constructed in accordance with the present invention.

FIG. 2 is a diagrammatic transverse section through a portion of roof constructed as shown in FIG. 1 with one form of roofing member made of extruded aluminum in accordance with the present invention.

FIG. 3 is a fragmentary section to an enlarged scale of the securing means and the joint between two members constructed as shown in FIG. 2.

FIG. 4 is a fragmentary transverse section of the fixing detail for the member shown in FIGS. 2 and 3.

FIGS. 5, 6, 7, and 8 are diagrammatic transverse sections of other forms of member made in accordance with the present invention.

FIG. 9 is a longitudinal sectional elevation showing another form of lapped joint made between two members produced in accordance with the present invention and having a reinforcement embodied therein.

FIGS. and 11 are diagrammatic longitudinal sections of members made in accordance with the present invention, the ends of which are closed.

FIGS. 12, 13, 14 and 15 are diagrammatic transverse sections of various forms of ceiling and insulating surfaces applied to roofs constructed with members made in accordance with the present invention.

FIG. 16 is a diagrammatic sectional view illustrating how several members constructed in accordance with the invention can be combined to form a building consisting of a series of portal frames.

FIG. 17 is another section of a building to illustrate the connection between an end wall and the roof.

FIG. 18 is a transverse section showing an alternative form of member to that shown in FIG. 2.

FIG. 19 is a fragmentary sectional view to an enlarged scale of the joint formed between two members constructed as shown in FIG. 18.

FIG. 20 is a fragmentary sectional view to an enlarged scale of the mounting portion of the member illustrated in FIG. 18, and a fixing clip shown engaged therewith.

FIG. 21 is a transverse section view of the member shown in FIG. 18 to which a stiffening member is shown attached.

FIG. 22 is a fragmentary sectional view showing an alternative form of the lower part of the stiffening member shown in FIG. 21.

FIG. 23 is a fragmentary section view similar to FIG. 19 showing to an enlarged scale and in engaged relation the male and female engagement portions two members constructed as in FIG. 18.

FIG. 24 is a diagrammatic transverse section of a line drawing of a modified form of member made in accordance with the present invention and produced by rolling.

FIGS. 25 to 28 are diagrams showing in section various forms of member made in accordance with the invention to show how the position of the centre of area varies with the change in proportion of the section of the member.

FIG. 29 is a transverse section showing a further form of structural member made in accordance with the present invention.

FIG. 30 is a transverse section of a second structural member for use in combination with a first structural member as shown in FIG. 29 or FIG. 18 or FIG. 19.

Turning first to FIG. 1 of the drawings. This illustrates diagrammatically a roofing arrangement according to the present invention, although it should be noted that for convenience the span shown is not as large in relation to the width of an individual member as would commonly be used. The members 2, interlock at the joints 4, and are secured near each end by fasteners (not shown) engaging with the transverse angle members 6.

In the following illustrations and descriptions transverse sections will be assumed to be viewed in the direction of the arrow A, and longitudinal sections in the direction of the arrow B.

A practical design of section for production in extruded metal is shown in FIGS. 2 and 3. In this example the member 168 is provided for fixing purposes with a thickened portion 170 in the form of an inverted channel on the inner faces of which are formed grooves 172 so proportioned that a fixing screw as described below may be engaged with them. The female engagement portion or receiving component 173 has an inner element 174 and an outer element 176 from which projects the abutment feature or re-entrant extremity 177. The surface at 173a on the female engagement portion forms a line of contact for a male member to be received therein. A groove 178 and a rib 180 are provided on the marginal male engagement portion or entering component 181 of the adjacent member. The outer element 176 has an upwardly inclined surface 176a that extends from the outer extremity thereof toward the line of contact 173a on the receiving component 173. The inner element 174 has a contact surface at 174a. On the assembly the male engagement portion 181 is inserted between the inner element 174 and the abutment feature 177 of the female engagement portion and locked by turning the added member to the aligned position so that the complementary surface thereon engages the line of contact 173a on the female engagement portion or receiving component 173. The mounting portion and joint are shown on a larger scale in FIG. 3, in which it will be seen that the outer element 176 has an abutment feature or re-entrant extremity 177 with which the rib forms a throat 182 which serves to prevent the passage of water through the joint by capillary action. The re-entrant extremity 177 extends toward the adjacent contact surface 174a on inner element 174 and provides a resistance to lateral compressive displacement of adjoining members by contact with the entering component 181.

The load which can be applied to a screw engaged with the grooves 172 of the channel 170 in FIGS. 2 and 3 is limited either by the mechanical strength of the screw and grooves or, particularly if several screws are closely spaced, by the tendency of the sides of the channel to be forced apart. To overcome this difiiculty by increasing the proportions of the channel 170 may well be uneconomic and upset the bending moment characteristics, and the expedient (or solution) illustrated in FIG. 4 may be adopted. In this arrangement the channel 170 is provided with lips 184 adapted to engage tapered inside walls 186 of a strip 188. When a bolt 190' is inserted and tightened to secure the channel 170 to a member 192 the action of the tapered walls 186 on the lips 184 prevents the sides of the channel being forced apart, and ultimately compresses them against the bolt, thus serving to lock it. To ensure that this action takes place it will be evident that it is desirable for the walls 186 of the strip 188 to make no greater angle with the axis of the screw than do the flanks of the threads of the bolt 190.

It will be evident that, both the stress in the material and the deflection of the members must be maintained within reasonable limits under the worst conditions of wind and dead weight loading likely to be encountered. This will require as much of the material of the member as possible to be concentrated in the upper and lower horizontal portions, and for the distance between them (the depth of the section) to be made as large as possible. In practice, considerations of ease of manu facture and aesthetic appearance will tend to impose a limit on the depth of the section, and the required strength will usually have to be achieved by an appropriate choice of thickness, as illustrated by thickened portions at 16 and 18 in FIG. 5. Such a section can be produced in a variety of materials for the use of appropriate processes. This figure and FIGS. 6, 7 and 8 are purely diagrammatic and the joint edges shown do not illustrate the features of the type of joint which would in practice he used.

An alternative arrangement to that shown in FIG. 5 is illustrated in FIG. 6, in which metal strips 20 are bonded into an extruded plastics material such as PVC at the thickened

portions

16 and 18. A similar section could be produced using glass fibre reinforced synthetic resin.

A means of reducing the amount of material in the sloping sides of the section is by reducing their number, and a transverse section is depicted in FIG. 7 of a member which is twice the Width of the members illustrated in FIGS. 5 and 6, and which has in this width only two sloping sides 22, in place of the four which would occur if two members were used of the width shown in FIG. 5 or FIG. 6.

Distortion of the cross section of the member under load limits the extent to which advantage can be taken of this change, and FIG. 8 represents a member similar to that shown in FIG. 7, stabilised by a tie 24 which can be formed either as a continuous web or by a number of individual strips bonded to the member at D, or alternatively by a number of long strips running at right angles to the longitudinal axis of the member and secured to the members at E, said strips extending over a number of members.

FIG. 9 shows a transverse joint between two longitudinally adjacent members of the type illustrated in FIG. 6, having metal reinforcing strips. The upper member 118 is cut away to leave only the reinforcing strips projecting, and these are then lapped over the lower member 120 and bolted through at 122. A shaped jointing piece 124, which may be secured by the bolts 122, is weathered to the upper member 118 by means of a suitable jointing compound at 126.

In cases where the required length of member is known at the time of manufacture closed ends can be formed: in other cases they will require to be attached by suitable joints. A number of configurations of closed ended members is illustrated in longitudinal section in FIGS. 10 and 11. FIG. 10 shows a member of uniform cross section, having a small finishing flange 128 at one end.

FIG. 11 shows a member in which the depth of section varies from the centre to the ends.

FIG. 12 illustrates diagrammatically the way in which a ceiling 146 can be fixed to the members by means of bolts 148 which engage the members at the mounting portions which in this example is positioned adajacent to the joint 4, in the same manner as the bolts securing the same members at each end of the span.

A common type of suspended ceiling consists of a rigid framework requiring only widely spaced attachment to the building, and providing the necessary support for the ceiling surface material. FIG. 13 shows a ceiling of this type, in which the framework 150 is secured at intervals by bolts 152 and in turn carries the visible ceiling 154.

Where appearance is not a primary consideration, and thermal insulation is required, such insulation can be bonded to the roofing member before erection. This form of construction is illustrated in FIG. 14 in which the thermal insulation 156 is bonded to the lower surface of each member 2 in such a way that butt joints 158 are formed when the members are interlocked.

Under suitable conditions use may be made of the mechanical strength of the thermal insulation material.

FIG. 15 shows a slab of insulating material 160 bonded at 162 to the lower surface of each member 2, each slab being arranged to meet the adjacent ones in lap joints 164. Further advantage may be taken of the addition of this material to the lower surface of the member 2 by thickening the upper surface at 166, in order to produce effectively a box member of high strength and rigidity.

It will be evident that members of the type described above can be used to form walls as well as roofs, and that by rigidly coupling walls and roof members, a building can be constructed which is effectively a series of portal frames Such a construction is illustrated in FIG. 16, in which the roof members, of which the one shown at 193 is typical, are secured rigidly to side wall members 195, be means of brackets 194 and screws 196. The anchorage of the wall members 195 to a base 198 need not be rigid, and is effected simply by angle pieces 200, screws 202 and holding down bolts 204. The gaps where the roof members 193 join the Wall members 195 are closed by filler pieces 206 which may be of relatively low strength material, for example unreinforced plastics, secured by screws 208 which may also be used to support a gutter (not shown) A means of securing the end wall of such a building is depicted in FIG. 17. End wall members 210, which may convenienly be identical with the side wall members 195 (FIG. 16) are screwed at the top to a section 212 engaging the end roof member 193 and are secured at the bottom to the base 198 in the same manner as the side Wall members 195. Another design of section (not shown) is used at the corners of the building to join the edges of the final side wall members 195 to the edges of the adjacent end wall members 210.

Numerous variations of constructional details are possible without departing from the scope of the invention.

Turning now to FIGS. l8, l9 and 20 it will be seen that the section closely resembles that shown in FIG. 2 except that the joint is somewhat changed in shape and has been moved to near the top. The same reference numerals are used for the same parts. The female engagement portion 173 is substantially semi-circular in section and the inner element 174 is foreshortened and instead of the end entering a groove in the male engagement portion 181 the end contacts a shoulder 2.14 thereon which serves to limit the turning movement on assembly. The male engagement portion 181 has been thickened so as to balance the mechanical properties of the section. The mounting portion is also slightly changed in shape being no longer tapered and provided with basal ribs 216 which serve three purposes. Firstly they increase the geometrical moment of inertia about a horizontal axis of the transverse section of the member. Secondly they provide an enlarged base on which the member is mounted and thirdly they provided convenient means for engagement by a fixing clip such as the clip 218 (FIG. 20) having resilient arms 220 pressed out of the vertical sides 222 the clip 218 having a thickened base 224 pierced and countersunk to receive the head of an attachment 226. It will be seen that the feature of the throat 182 is retained. It will be noted that the outer element 176 of the female engagement portion 173 extends as a lip 230 further beyond the abutment feature 177 than the example shown in FIG. 3 and that the point of closest approach to the lip to the stem 228 of the male engagement portion 181 indicated by the dimension a is substantially vertically beneath the tip of the lip 230 of the outer element 176 so that the surface tension of any water droplets bridging this gap would contribute to prevent such droplets reaching the point of contact of the abutment feature 117 with the male engagement portion 181. It will be noted that male engagement portion 181 is grooved to receive the top corner of the squared off end of the abutment feature 177.

In FIG. 21 there is shown a stiffening member 232 having a mounting flange 234 recessed to receive and locate the basal ribs 216 of the member 168 and pierced at intervals to receive bolts 236. A flange 238 is formed at the bottom of the stifiening member 232.

As can be seen from FIG. 22 the flange 238 can be replaced by an attachment portion 240 similar in shape to the mounting portion 170. The stiffening member 232 need not extend for the full span of the member 168.

FIG. 23 shows a joint having male and female engagement portions similar in shape to those shown in FIG. 19 but provided with additional throats two of which 242 and 244 are in the female portion 173 thickened for this purpose and one 246 is in the male portion 181. Obviously the number and position of such throats can be varied and need not be provided in both male and female portions.

FIG. 24 illustrates a suitable shape for a different design of member produced by a rolling process. The member 248. The female engagement portion 250 has inner and outer arcuate elements 252 and 254 the latter terminating in the abutment feature 256 which is directed towards the inner element 252. The male engagement portion 258 is in the form of a flattened rail produced by turning the edge of the sheet back on itself and having semicylindrical ends 262 and 264 the rail head 258 sloping upwardly and outwardly thus providing contact lines with the inner and outer elements of the adjoined member the inner contact point being above the outer as with the previously described form illustrated in FIGS. 2 and 3. Adjacent to but distinct from the male engagement portion 258 is a roll 266 for engagement by hook securing means. Such a member formed by rolling lends itself to use in a similar way as previously described for the member formed by extrusion.

Turning now to the diagrams shown in FIGS. 25 to 28 inclusive. These are included to show how the centre of area of a member may move with a change in shape. In these figures the members are shown touching upper and lower developing

surfaces

268 and 269 respectively. In FIG. 25 the centre of area 270 is only a distance below the top enveloping surface 268 equal to of the distance between said enveloping surfaces. In FIG. 26 this distance is /5 d providing a member of greater strength in relation to the amount of material used. FIG. 27 illustrates the proportions and position of the centre of area of the member whose section is shown in FIG. 18 in which the distance is 75 a. In FIG. 28 there is shown the optimum form in which the greatest strength is obtained in relation to the amount of material used and the centre of area 270 in half way up the section.

Referring to FIG. 29 it will be seen that the structural member there shown has female engagement portions 173 identical with that shown in FIG. 18 at each longitudinal edge. This provides a symmetrical design of member giving the advantage that any deflection under a load applied in the plane of symmetry will be in the direction of the load. Obviously such a member can only be used in combination with one having a male engagement portion.

Just such a structural member for use in combination with the one shown in FIG. 29 is shown in FIG. 30 where once again a symmetrical design is employed having two male engagement portions 181 and a roof or wall can be built using these two symmetrical forms of structural members alternately.

In both FIGS. 29 and 30 the structural member is shown with a mounting portion 170 but it is to be understood that if desired the mounting portion can be dispensed with in either unit of the combination. Moreover FIG. 30 is only to be regarded as one example of the form of structural member which can be combined with the form of structural member shown in FIG. 29. It is regarded that these members 29 and 30 can be considered sub members which, when joined together would result in a combined member having a receiving component at one end and an entering component at the other end.

Although joints between members have been drawn simply as if the two members were lapped over each other and held in contact, it is understood that throating and sealing strips may be added to any of the joints if severe conditions of use render it necessary.

The adjacent members may be identical in physical and visual characteristics or may differ for example every alternate member may be weaker than others and be supported thereby.

One of the advantages of the above described members is that they can be used for supporting dead weight loads such as heating and ventilating installations and that the imposition of such loads can be arranged to reduce the peak stresses for example by partly offsetting the upwardly directed forces on a roof resulting from wind.

By the application of this invention it is possible to provide a roofing system consisting of members adapted to span substantial distances Without intermediate support and to be engaged with each other or with a jointing element at adjacent edges to form a weatherproof joint capable of transmitting mechanical load.

What I claim and desire to secure by Letters Patent is:

1. A structural assembly for use in building a roof, comprising a first member and a second member,

said first member having outer and inner faces and having engagement means constituting opposite edges of the member adapted for edge to edge engagement with complementary engagement means on said second member,

at least one of said first member engagement means lli facing downwardly and received over complementary engagement means on said second member assembled therewith by relative rotation of the members,

said one engagement means on the first member having inner and outer elements of which the outer element is on the outer face of said first member and the inner element is on the inner face of said first member,

said inner element having a contact surface on the inner portion of its outer end,

said inner and outer elements joining together forming a concave inner surface line of contact facing downwardly on at least one of their inner ends that receives thereagainst complementary engagement means on the second member on its relative rotation thereagainst into an aligned position in which relative transverse displacement in any direction is immediately resisted by direct contact of the inner concave surface line of contact with a complementary surface on said second member;

said outer element of said one engagement means of said first member having a re-entrant extremity extending from adjacent the outer extremity of the outer element toward the adjacent contact surface on said inner element,

the engagement means on the first member receiving the complementary engagement means on the second member between the re-entrant extremity and the inner element on the first member engagement means, the complementary engagement means on the second member being turnable about said re-entrant extremity towards an aligned position of the first and second members, said inner element contact surfaces providing resistance to lateral compressive displacement of the first and second members,

said downwardly facing engagement means on the first member having at least one throat extending upwardly into said concave surface line of contact therein providing a barrier to the travel of moisture by capillary attraction.

2. A structural assembly for use in building a roof,

comprising a first member and a second member,

at least one of said first member engagement means facing downwardly and received over complementary engagement means on said second member assembled therewith by relative rotation of the members,

said outer element of said one engagement means of said first member having a re-entrant extremity ex tending from adjacent the outer extremity of the outer element toward the adjacent contact surface on said inner element,

said contact surface in said downwardly facing engagement means of the first member opposite to said re-entrant extremity having an upwardly inclined reentrant portion adapted to be received in a downwardly extending recess in an upwardly projecting entering component on said second member complementary engagement means on relative rotation into engagement therewith.

3. A structural assembly for use in building a roof,

comprising a first member and a second member,

said first member having outer and inner faces and having engagement means constituting opposite edges of the member adapted for edge toedge engagement with complementary engagement means on said second member,

said one engagement means on the first member having inner and outer elements of which the outer element is on the outer face of said first member and the inner element is on the inner face of said first memher,

said re-entrant extremity on the outer element of said engagement means of said first member having its end spaced a relatively close distance to form a gap with the adjacent complementary means on the second member that turns about said re-entrant extremity towards the aligned position of the first and second members so that the surface tension acting on any water droplets bridging the gap would contribute to prevent such droplets from moving further upward toward said concave inner surface line of contact on said downwardly facing engagement means of the first member.

4. A structural assembly for use in building a roof,

comprising a first member and a second member,

the engagement means on the first member receiving the complementary engagement means on the second member between the re-entrant extremity and the inner element on the first member engagement means, the complementary engagement means on the second member being turnable abount said reentrant extremity towards an aligned position of the first and second members, said inner element contact surfaces providing resistance to lateral compressive displacement of the first and second members,

at least one of said first and second members having a depending projection therefrom forming a mounting portion for the structural assembly, said projection being adapted to receive a securing means.

5. A structural assembly according to claim 4 wherein said depending projection includes a rib portion adapted to receive a hook shaped securing means.

6. A structural assembly according to claim 4 wherein said depending projection is an internally ribbed channel opening downwardly and adapted to receive a threaded securing screw.

7. A structural assembly according to claim 6 wherein the channel is formed with tapered lips for engagement with a lip restraining socket means.

8. A structural assembly according to claim 6 wherein said channel is also provided with external ribs for engagement by clip shaped securing means.

9. A structural assembly for use in building a roof, comprising a first member and a second member,

at least one of said first member engagement means facing engagement and received over complementary engagement means on said second member assembled therewith by relative rotation of the members,

said one engagement means on the first member having inner and outer elements of which the outer element is on the outer face of said first member and 11 the inner element is on the inner face of said first member,

said inner and outer elements joining together forming a concave inner surface line of contact facing downwardly on at least on of their inner ends that receives thereagainst complementary engagement means on the second member on its relative rotation thereagainst into an aligned position in which relative transverse displacement in any direction is immediately resisted by direct contact of the inner concave surface line of contact with a complementary surface on said second member;

the engagement means on the first member receiving the complementary engagement means on the second member between the re-entrant extremity and the inner element on the first member engagement means, the complementary engagement means on the second member being turnable about said reentrant extremity towards an aligned position of the first and second members, said inner element contact surfaces providing resistance to lateral compressive displacement of the first and second members,

said first and second members having insulating means at the underside thereof.

10. A structure for use in building a roof comprising in combination:

(a) a first structural member having engagement means constituting opposite edges thereof engageable with complementary engagement means of adjacent members;

(b) a second structural and adjacent member having engagement means constituting opposite edges thereof for engagement with an engagement means on the first structural member;

(c) said first structural member having at least one downwardly facing receiving component forming at least a part of at least one said engagement means;

(d) said second structural member having at least one upwardly projecting entering component for the receiving component on said first structural member;

(c) said receiving component on the first structural member engaging over said upwardly projecting entering component on the second structural mem- I her and on relative rotation in engagement therewith in the direction to lower said opposite edge on said entering component to a position in which relative transverse displacement in any direction is immediately resisted by direct contact of said components; (f) said receiving component on the first structural member having an upwardly inclined surface on a portion thereof extending from an outer extremity thereof towards a line of contact therein for said entering component; (g) a re-entrant extremity on said receiving component, and (h) a contact surface in said receiving component opposed to said re-entrant extremity providing resistance to lateral compressive displacement of adjoining members by contact with said entering component;

said downwardly facing receiving component of said first structural member is generally C- shaped, the upper leg portion thereof forming said portion thereof extending from an outer extremity thereof towards said line of contact therein, said line of contact therein being along the mid-portion between the legs of the C- shape, the other leg of the C-shape of the receiving component forming said contact surface and said re-entrant extremity extending from the end of said upper leg of the C-shaped receiving component normal to the other leg, said upwardly projecting entering component of the second structural member having a portion extending upward adjacent said second leg of the receiving component to a position under said re-entrant extremity of the receiving component and a terminal portion extending at an angle upwardly toward and to said line of contact on the receiving component; said re-entrant extremity on said receiving component has its end spaced a relatively close dis tance to form a gap with the adjacent portion of the upwardly projecting entering component of the second structural member so that surface tension acting on any water droplets bridging the gap would contribute to prevent such droplets from moving further upward toward said line of contact on said receiving component for said entering component. 11. A structure for use in building a roof comprising in combination:

((1) said second structural member having at least one upwardly projecting entering component for the receiving component on said first structural member;

(c) said receiving component on the first structural member engaging over said upwardly projecting entering component on the second structural membet and on relative rotation in engagement therewith in the direction to lower said opposite edge on said entering component to a position in which relative transverse displacement in any direction is immediately resisted by direct contact of said components;

(f) said receiving component on the first structural member having an upwardly inclined surface on a portion thereof extending from an outer extremity thereof towards a line of contact therein for said entering component;

(g) a re-entrant extremity on said receiving component, and

(-h) a contact surface in said receiving component opposed to said re-entrant extremity providing resistance to lateral compressive displacement of adjoining members by contact with said entering component;

said downwardly facing receiving component of said first structural member is generally C- shaped, the upper leg portion thereof forming said portion thereof extending from an outer extremity thereof towards said line of contact therein, said line of contact therein being along the mid-portion between the legs of the C- shape, the other leg of the C-shape of the receiving component forming said contact surface and said re-entrant extremity extending from the end of said upper leg of the C-shaped receiving component normal to the other leg, said upwardly projecting entering component of the second structural member having a portion extending upward adjacent said second leg of the receiving component to aposition under said re-entrant extremity of the receiving component and a terminal portion extending at an angle upwardly toward and to said line of contact on the receiving component;

said downwardly facing receiving component has a throat formed adjacent said re-entrant extremity and said terminal portion of the upwardly projecting entering component that extends at an angle upwardly toward and to said line of contact on the receiving component providing a barrier to the travel of moisture by capillary attraction.

12. A structure for use in building a roof comprising in combination:

() said first structural member having at least one downwardly facing receiving component forming at least a part of at least one said engagement means;

(c) said receiving component on the first structural member engaging over said upwardly projecting entering component on the second structural member and on relative rotation in engagement therewith in the direction to lower said opposite edge on said entering component to a position in which relative transverse displacement in any direction is immediately resisted by direct contact of said components;

(g) a re-entrant extremity on said receiving component,

and

(h) a contact surface in said receiving component opposed to said re-entrant extremity providing resistance to lateral compressive displacement of adjoining members by contact with said entering component;

said downwardly facing receiving component of said first structural member is generally C- shaped, the upper leg portion thereof forming said portion thereof extending from an outer extremity thereof towards said line of contact therein, said line of contact therein being along the mid-portion between the legs of the C-shape, the other leg of the C-shape of the receiving component forming said contact surface and said re-entrant extremity extending from the end of said upper leg of the C-shaped receiving component normal to the other leg, said upwardly projecting entering component of the second structural member having a portion extending upward adjacent said second leg of the receiving component to a position under said re-entrant extremity of the receiving component and a terminal portion extending at an angle upwardly toward and to said line of contact on the receiving component;

said downwardly facing receiving component has at least one throat extending upwardly into said line of contact therein at said mid-point between the legs of said C-shape providing a barrier to the travel of moisture by capillary attraction.

13. A structure for use in building a roof comprising in combination:

(a) a first structural member having engagement means constituting opposite edges thereof engageable with complimentary engagement means of adjacent members;

(b) a second structural and adjacent member having engagement means constituting opposite edges thereof for engagment with an engagement means on the first structural member;

(g) a re-entrant extremity on said receiving component,

and

said downwardly facing receiving component of said first structural member is generally C- shaped, the upper leg portion thereof forming said portion thereof extending from an outer extremity thereof towards said line of contact therein, said line of contact therein being along the mid-portion between the legs of the C-shape, the other leg of the C-shape of the receiving component forming said contact surface and said re-entrant extremity extending from the end of said upper leg of the C-shaped receiving component approximately normal to the other leg, said upwardly projecting entering component of the second structural member having an arcuate face received within said C-shaped receiving component, a notch in a face thereof adjacent the end of said re-entrant extremity on said receiving component that forms a fulcrum for pivoting said upwardly projecting entering component in said C-shaped receiving component and a shoulder therein approximately opposite to said notch therein forming an abutment for the extreme lower end of said other leg of the receiving component thereby limiting the rotation of the upwardly projecting entering component and leaving a throat space between said upwardly projecting component and the adjacent reentrant extremity of the receiving component.

14. A structure for use in building according to claim 13 wherein said mid-portion of the C-shaped receiving components at said line of contact has at least one throat recess extending thereinto providing a barrier to the travel of moisture by capillary attraction.

15. A structure according to claim 13 wherein said arcuate surface of said upwardly projecting entering component has at least one throat recess extending thereinto providing a barrier to the travel of moisture by capillary attraction.

16. A structure according to claim 14 wherein said arcuate surface of said upwardly projecting entering component at a position offset from the threat in said receiving component has at least one throat recess therein providing an additional barrier to the travel of moisture by (f) said upwardly projecting entering component of capillary attraction. said other engagement means on said sheet material 17. In a structural assembly for use in building a roof member being in the general form of a flattened rail made of sheet material members fastened together, having the edge of the sheet of material turned back (a) a sheet material member having engagement means 5 on itself with semicylindrical ends, said semicylindriconstituting opposite edges thereof, one of said engagement means having a downwardly facing receiving component and the other engagement means having an upwardly projecting entering component, each respectively engageable with complementary engagement means of adjacent members;

(b) said downwardly facing receiving component forming at least a part of at least one said engagement cal ends and the sheet material joining therebetween sloping upwardly and outwardly from the edge and thereby the semicylindrical portions provide contact lines with inclined contact surfaces of a receiving component of an adjacent structural member, the upper semicylindrical end thereby being an inner contact point and the lower semicylindrical end being the outer contact point whereby to provide barriers to means for engagement over an upwardly projecting the travel of moisture by capillary attraction. entering component of an adjacent member and on relative rotation in engagement therewith in the direction to lower said opposite edge on said entering component to a position in which relative transverse References Cited UNITED STATES PATENTS displacement in any direction is immediately regf i stricted by direct contact of said components; 1998860 4/1935 B i 9 X (c) an upwardly inclined concave surface on a portion 2018423 10/1935 q g 6 of said receiving component extending from an outer 3238687 3 61 39 extremity thereof towards a generally horizontal line 1967 Tlsbo 52539 X of contact therein for said entering component; 7/1944 Slaughter (d) a re-entrant extremity on said receiving component 17 11/1967 P 52 309 forming an abutment; 1 3,191,724 6/1965 Rldder 52588 X (e) a contact inclined concave surface in said rece'v- FOREIGN PATENTS ing component joining with said generally horizon al line of contact and opposed to and :facing said fi st 231013 1925 Great Bntam' mentioned upwardly inclined concave surface a d JOHN E. MURTAGH Primary Examiner said re-entrant extremity providing resistance to lateral compressive displacement of adjoining members by contact with said entering component; and

US. Cl. X.R.

53 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 3 466 8332 Dated September 16 1969 Inventoflx) Adrian Anthony Cecil March It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In column 10, line 69, cancel "engagement" and insert --downwardly SIGNED MU SEALED JAN 6 1970 (SEAL) Atbest:

Edward M. Fletcher, Ir. WILLIAM E. saHuYLxR, .m.

Attestine Officer or Pumas