US2365129A - Built-up roof - Google Patents

Description

A. WINDING BUILT -UP ROOF Dec. 12, 1` 944.

Filed June '7, 1945 OEIMN www@ w .n 0 n mu Patented Dec. 12, 1944 UNITED STATES PATENT OFFICE `2,365,19 BUILT-UP ROOF Y Arthur Winding, Milwaukee, Wis. Application June 7, 1943, Serial No. 489,899 4 o1aims. (c1. 10s- 26) for the joint between roof and vertical members.

One of the objects yof the invention is to create a flashing which will not warp and null away from the Vertical members under the iniiuence of climatic conditions.

-Another object of the invention is to create a flashing which will be weatherproof without requiring 'the addition of counterfiashing.

A still further object of the invention is to form a weatherproof flashing wthoutthe aid of nailing strips, prepared flashing bricks, raggle blocks, and metal flashing forms inserted "in the vertical members.

The foregoing 'objects are accomplished by bonding to the vertical member (to a height just above the top of the vertical leg of the cant strip specified) a single sheet of heavy rooiing felt.

This sheet has an upper portion, which is not at-` tached to the vertical member, of sufficientv size to permit such portion to be folded downwardly over and completely cover the sloping leg of the specied can't strip. The specied cant strip is then fixed in place so that its vertical surface presses against the sheet of felt. Built-up roofing materials are now applied. These comprise successive layers of asphalt and felt. Such layers have portions extending up on and substantially covering the sloping surface of the cant strip. The upper portion of the sheet of roofing felt is folded down lover the cant strip andthe roofing material and bonded to such material. A final layer of asphalt is then applied to the outer sury face of such `folded over portion. To effect a complete seal a bead of plastic roofing cement is placed in the joint between the wall and the fold line of the sheet of felt.

With flashing thus constructed, the cant strip not only helps hold the flashing in place, but it protects it from the bad eiects of climatic conn ditions. The bond between the dashing and the vertical member is, therefore, maintained intact and waterproof `for long periods. The tendency of the flashing to warp and pull away from the vertical member is eliminated. Because of the double action of the adhesive force of the roofing cement and the pressure of the cant strip, the seal between dashing and vertical member is main tained `sufliciently tight and durable to eliminate the necessity of added protection derived from co-unterashing. The pressure exerted by the cant strip maintains the dashing against the vertical member and hence there is no need ofnailing strips, flashing bricks, raggleblocks, and metal flashing forms in such vertical member.

The novel features, which are considered characteristic of the invention, are set forth with pare ticularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of a specific embodiment when read in connection with the accompanying drawing, in which:

Figure 1 is a sectional view through the joint between the roofing support and a vertical wall showing the improved flashing;

Figure 2 is a fragmentary, greatly enlarged sectional view taken on the line 2 2 of Figure l;

Figure 3 is a fragmentary, greatly enlarged sectional View taken on the line 3-3 of Figure 1.

Referring in greater detail to the drawing, the support for the deck 3 is provided by beams I. The end of the beams 'l may be supportedI in the vertical concrete wall 2 in the approved manner. Insofar .as this invention is concerned, the deck 3 may `comprise lWood sheathing, concrete, tile, or gypsum block. The vertical wall 2 is illustrated as consisting of concrete; however, it may dashing `is vto apply to the side of the wall '2 an vio also consist of brick or-gypsum bl'ock.

The iirst step in the method of constructing the asphalt primer 4, such as is commonly used for such purpose. The coating of primer should eX- tend up the surface of the wall to a point above the top of the specied cant strip 9. Various sizes of cant strips may be specified depending upon the size of the installation. When the primer has set, a thick layer '5v of plastic roofing cement is troweled onto the wall 2 over the surface previously primed. Then a sheet ii of heavy roofing felt is pressed on and into the layer 5 of plastic roofing cement. The sheet E has a lower portion which is substantially extensive with the area covered, and it is this portion which is bonded tothe wall 2 by the cement i5. The sheet 6 also has an upper unattached portion which matr be folded down about the top of the cant stript onto the sloping surface of such cant strip. The area of such upper portion will substantially cover the sloping surface of the cant strip when so folded. After the sheet 6 has 'been applied, the next step is to put the wo-odencant strip 9 in place.

The cant strip 9 is placed with its vertical surface tightly engaging the layer 6 and its horizontal surface resting upon the deck 3. In the embodiment shown, the cant strip 9 is comprised of wood, and in such instance it is rmly pressed against the lower portion of sheet 6 and securely nailed in place by nails I Il. The sheet Ii is thus maintained in a watertight connection with the Wall 2 by the action 0f both the layer 5 of plastic roofing cement and the wooden cant strip 9. In installations where the deck 3 is comprised of concrete, a concrete cant strip is used instead of a wooden cant strip. The concrete is laid wet and formed to the same shape as the wooden cant strip. The weight of the concrete plus its adherence to the surface of the concrete deck will be sufficient to hold the cant strip in place with its vertical surface firmly engaging the sheet 6. After the cant strip is positioned as described, the next step consists in laying the main roofing material.

Built-up roofs customarily comprise successive layers of asphalt, pitch, or other bituminous bonding material and roofing felt. The initial layer I I of asphalt or bituminous bond is mopped while hot onto the surface of the deck 3 and up on the sloping surface of the cant strip 9. Immediately the first layer I2 of roofing felt is pressed on the layer II. The layer I2 also extends up on and substantially co-extensive with the sloping surface of the cant strip 9. Then a second layer I3 of asphalt or bituminous bond is similarly mopped in place. On the layer I3 is pressed a second layer I4 of roofing felt. It also extends up on and substantially co-extensive with the sloping surface of the cant strip 9. In some installations it may be preferable to have one or two more successive layers of bonding material and felt. When the last of the desired layers of felt is laid, the final layer I5 of asphalt or bituminous material is mopped on. The layer I5 also extends up the sloping side of the cant strip 9. As soon as the layer I 5 is applied on the sloping side, the upper unattached portion of the sheet 6 is folded downwardly about the top of the cant strip 9 and pressed into the layer I5. The outer surface of this folded over portion is then covered with a final layer I6 of asphalt or bituminous bond. To make certain that no moisture will seep in between the concrete wall 2 and the sheet 6, the joint formed between the wall and the fold in the sheet 6 is filled with plastic roofing cement as indicated at I1.

The fiashing thus formed is securely held against the vertical wall 2 without the necessity of having in that vertical wall any specially prepared flashing bricks, raggle blocks, or metal flashing forms. The cant strip 9 performs the function heretofore performed by such special devices. The cant strip 9 also performs the additional function of providing a buffer which absorbs to some extent changes in temperature and protects the flashing from the direct rays of the specific embodiments of the invention, many modifications thereof are possible. The invention is not to be restricted except so far as is necessitated by the prior art and the spirit of the appended claims.

I claim:

1. The method of flashing a deck type roof having a coping wall, including adhering the lower portion of a vertical sheet of roofing material to said wall with its upper portion unattached, securing a cant strip in place so that its vertical side engages the adhered lower portion of said sheet, applying roofing material on the roof so that it extends up the sloping side of said cant strip, and folding said upper portion down over the sloping side of said cant strip and bonding it to the roofing material previously applied to said sloping side.

2. A weather-proof covering for the juncture of a roof and a vertical member comprising, a sheet of vertically extending roofing material having a lower portion and an upper portion, a layer of plastic roofing cement between the vertical member and said lower portion whereby said lower portion is adhered to said vertical member, a cant strip having a vertical surface engaging with said lower portion to maintain the same in close surface-to-surfacel contact with said cement, said cant strip having a horizontal surface fixedly engaged with the surface of the roof, said cant strip having a sloping surface extending from the roof to the vertical member, a weather-proof built-up roof having the materials comprising it extending from the surface of the roof up said sloping surface and substantially covering the same, said upper portion being folded about the top of said cant strip and bonded to said roof. and a bead of plastic roofing c ement inserted in the joint between the vertical member and the fold in said sheet.

3. A weather-proof covering for the juncture of a roof and a vertical member comprising: a sheet of vertically extending roofing material having a lower portion adhered to the vertical member and an unattached upper portion; a cant strip having a vertical surface engaging with said lower portion, a horizontal surface secured to the roof, and a sloping surface; and a layer of roofing material extending from the roof up on said sloping surface; said upper portion being folded down over said cant strip and bonded to said layer on said sloping surface.

4. In a roofing construction, a roof deck and an upstanding marginal wall therefor, a sheet of roofing material having a lower portion and an upper portion, said lower portion being adhered to said upstanding marginal wall, a rigid member having a surface flatly engaging with said lower portion of the sheet, means fixedly securing said rigid member to press the lower portion of said sheet against said upstanding wall, and a layer of roofing material on said roof deck having a marginal edge portion terminating adjacent said marginal wall, the upper portion of-said sheet being folded downwardly of said rigid member into bonded engagement with said layer of roofing material at a point spaced from said marginal edge, with the said rigid member and the said marginal edge enclosed within said fold.

ARTHUR WINDING.

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