duratile roofing system installation guide

8/12/2019 Duratile Roofing System Installation Guide

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INSTALLATIONGUIDE

DURATILE ROOFING SYSTEM


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The Duratile Roofing System

Duratile Incorporated is pleased to introduce an innovative roofing system which iswholly owned and manufactured on our beautiful island of Barbados. Our new facility inLears Quarry, Lears, St. Michael features state-of-the-art equipment and processingtechnologies to provide you with the highest quality product.

Duratile Slate Roofingreplicates the classic look of natural slate and adds prestigeand character to any architectural style of building. The low gloss variegated color andnatural slate colors enhance the design of your home. The unique hinged ridge capsystem allows the flexibility to accommodate roof angles from 5 - 90. This range ofmovement allows a single component to adapt to a variety of roof pitches. With theDuratile Roofing System, you will get the beauty you want plus the performance you

demand.

DuratileSlate Roofingis manufactured from a durable plastic composite materialextending your roofs life cycle substantially. Thanks to our extensive Research andDevelopment efforts, which have resulted in a proprietary resin compound, the productexhibits superior structural integrity and impact resistance. The color through processeliminates the need for painting or protective sealant throughout the life of the product.

Duratile Slate Roofing, while providing the look and texture of slate, is lighter in weightthan traditional slate or clay tile systems and therefore requires no additional structuralreinforcement when replacing conventional roofing nor does it require you to undo any

structural requirements for the new applications.

The Duratile Roofing System provides economical and ecologically sound roofingsolutions for today and the future of our island.


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GENERAL CONSTRUCTION GUIDELINES

The design of the roof is probably the most important consideration relating to theperformance of any roofing system. Typically, the steeper the roof pitch, the better theperformance of the roof design in adverse conditions. On the island of Barbados this isextremely important in that we often endure severe storms with high winds and theassociated wind driven rain.

For your house to remain dry and un-damaged during these occasions of adverseweather, Duratile has designed the slate shingle with weather resistant features such asdrain channels to prevent water migration into your home. To insure that the mostweather tight roof may be installed on your home, Duratile has developed this

installation manual which recommends the most current thinking in weatherproofingyour structure.

While many of the recommendations supplied in this manual are not necessarilyrequired by code, it is suggested that these recommendations be adhered to provide thebest long term performance for your roof installation.

At minimum, all installers of the Duratile Roofing System shall be fully familiar with andequipped to install the product in a fully qualified manner and acceptable to the architectspecifying the roofing system and the general contractor responsible for the finishedproduct.

GENERAL APPLICATION DETAILS

Regardless of the style of roof the Duratile Roofing System is being installed on, thefollowing basic application details must be observed:

Roofing tiles must be doubled at all eaves. Butts of the first course of tiles should project 3/4" beyond the fascia at allrakes and eaves.Spacing between adjacent roofing tiles should be a minimum of 1/8" and amaximum of 1/4".Install a minimum of two (2) fasteners per tile. Use fastener guide openingswherever possible for the required exposure in the succeeding course.It is recommended that in situations where a fastener opening is not readily


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available (such as cut tiles fitting valleys, hips, ridges etc.), a 3/16" diameter holebe drilled for fastening to minimize stress in the tile and to allow movement

caused by expansion and contraction.Joints in any one course should be separated 6" from joints in the adjacentcourses.

SLOPES (Roof Pitch)

The Duratile Roofing System may be applied on any roof with a slope of 15 or greater.The standard roofing tile may also be applied to exterior walls utilizing acceptableconstruction practices as outlined in this manual.

DECKING

The Duratile Roofing System should be applied over solid decking 3/4" thick or greater.Deck sheathing may consist of composite board panels, such as oriented strand board,plywood or wood planking. In re-roofing applications the existing roof must becompletely removed down to the deck. The deck must be solidly fastened to thebuilding structure in accordance with applicable building codes and provide a smoothbase for application of the roofing tiles.

SELF ADHERING MEMBRANE

It is recommended, but not required, that a self-adhering waterproofing membrane beapplied at all eaves, hips, ridges and roof projections.

The self-adhering membrane should be comprised of modified asphalt with a consistentlayer of adhesive applied to one side, with a release paper applied to the underside.The membrane shall be comprised of a substrate material and rubberized asphalt with a1/4" bead of asphalt running continuously down each side of the roll.

Self-adhering membrane should be applied at the eaves extending 36" up the slope to aline not less than 12" beyond the face of the exterior wall. The membrane shall overlapthe apron flashing at the eaves to prevent water damage under the flashing.

Self-adhering membrane should be applied at ridges and hips extending a minimum of18" either side of the centerline of the ridge or hip.


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Self-adhering membrane should be applied to all roof projections and penetrations in amanner which will prevent water damage to the roof, for example around dormers,

skylights, vents, chimneys etc...

UNDERLAYMENT

Underlayment is recommended to be 30# plain roofing felt, type II, organic or inaccordance with the local code of jurisdiction and installed to the manufacturersspecification.

Install one ply of underlayment over the entire surface of the roof with the exception ofcut-out areas for vents etc..

Lay underlayment horizontal to the roof slope with a minimum headlap of 2" and asidelap of 4" or in compliance with manufacturers specifications. Fasten or stapleunderlayment sufficiently to hold in place until roofing tiles are installed.

TORCH DOWN MEMBRANE

The islands reside in a very harsh environment which is hot and subjected to a greatdeal of wind driven rain. The recommendation for underlayment contained in thismanual are at best a minimum requirement for the climate.

Duratile Inc. strongly recommends that the homeowner considers applying torch downmembrane over the entire roof prior to installing the roofing shingles.

This approach will provide the most weather tight installation as well as maximize thefunctioning life of the roof.

SHEET METAL FLASHING

All sheet metal flashing shall be a minimum of 26 ga stainless steel, 16 oz. copper or0.032" aluminum.

Install sheet metal flashing along eaves, rake edges, valleys, ridges, hips and all roofprojections and penetrations.

Sheet metal flashing work shall be manufactured in accordance with the best standard


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practices of the industry; with joints locked, cleated, caulked as required, and exposededges hemmed. Allowance shall be made in all work for expansion and contraction

without compromising the waterproofing integrity of the structure.

Mitered corners shall be straight and profiles level as required to suit the specific siteconditions, with flat surfaces free of distortion and face nailing.

All free edges of metal flashing shall be reinforced by a fold of at least " wide, set outslightly and presenting a straight line and neat finish.

Form flashing in the longest possible lengths to minimize water migration and allow forappropriate expansion and contraction.

All flashing should be fabricated in a shop where possible, with proper sheet metaltools. Lock seams should be provided for all corners and intersections where possible.

VENT STACKS

It is recommended that soil vent pipes be installed with a pre-manufactured self-flashing base and sealed to the vent pipe projection with an elastomeric seal or boot.

All vent flashings shall be installed in accordance with the manufacturersrecommendations.

ROOF VENTS

Roof or ridge vents shall be pre- manufactured from aluminum, galvanized steel, copperor plastic, sized to comply with the appropriate building code.

Ridge vents shall have waterproof ends, caps and connectors as required to completethe installation in a manner recommended by the manufacturer.

ADHESIVES & SEALANTS

The contractor should ensure that all construction adhesives and sealants used in the

installation of the roof comply with appropriate codes and are compatible with theroofing system.


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A list of approved sealants and adhesives may be obtained from Duratile Inc..

FASTENERS

It is recommended that each Duratile Roofing Tile be attached with two non- corrosivescrews of sufficient length to fully engage the roof substrate. These fasteners may beapplied either manually or with pneumatic nailing equipment.

The recommended length for these screws follows:3/4" starter course

1" first course1 1/4" main course1 3/4" caps and hips

Where fastening may be marginal such as around chimneys, valleys, hips, ridges etc.,use a recommended construction adhesive in addition to screws to ensure that the tilesare properly secured to the roof.

Approved fasteners are to be manufactured from electro-galvanized steel, ASTM 641,Class 1; Type 304 or 316 passivated stainless steel, copper or aluminum.

COMPATIBILITY

The roofing contractor must ensure that all materials used in conjunction with theinstallation of the roof are compatible with the Duratile roofing system and each other.

Failure to use compatible materials with a life span equal to the roofing shingles will notonly shorten the life of the roof but may void the warranty offered by Duratile Inc.

All installations must comply with the current Barbados building code and anyappropriate updates to this code.


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THE DURATILE ROOFING SYSTEM

The Duratile roofing system consists of a standard roofing tile and a unique hinged ridgecap.

The standard roofing tile has nominal dimensions of 12" X 16". The slate look tilefeatures a rain gutter on the upper face to minimize water migration under eachsucceeding course. Nailing points are through molded for convenience and layoutreference marks are incorporated into the face to assist in installation(Figure 1).

The rear side of the roofing tile is cored to minimize the weight. Cut locations for boththe starter course and the half shingles are adjacent to molded rib in place structures(Figure 2).


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The diagram below (Figure 3) illustrates the typical tile layout required for a weather-tight roofing installation.

The hinged ridge cap consists of two parts, left and right halves (Figure 4).

As with the standard roofing tile, the ridge cap incorporates rain gutters and throughmolded nailing points.

The rear side of the roofing tile is cored to minimize the weight. Reference marks are

molded into the rear surface to assist in cutting major reference angles used inconstruction of a building (Figure 2).


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The tapered hinge pin allows the ridge cap to rotate up to 90 to provide installationadjustment to fit a variety of roof styles (Figure 5).

The diagram below (Figure 6) illustrates the typical tile layout required for a weather-

tight roofing installation.

GENERAL INSTALLATION DETAILS

For the most attractive visual appearance, the contractor should mix tiles from differentbundles to take advantage of minor variations between batches and ensure randomshading on the finished roof surface.


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After the roof surface has been prepared inclusive of flashing, self- adhering membraneand underlayment, the installation of the tiles may begin.

STARTER COURSE

The starter course consists of the upper portion of the tile (see figures 1 & 3). Thecontractor should save the lower portions of the tile for use at hips, ridges and valleys.

Install the starter course by cutting one tile in half and then alternating with a full widthtile extending beyond the eaves and rakes by 3/4" ( Figure 7 ). Each starter tile shouldbe fastened with two (2) 3/4" screws in a parallel line with the eaves.

It is recommended that a 3/16" diameter hole be drilled for each screw to preventfastening stress build-up in the tile and to allow for expansion and contraction shouldthe provided fastening points not be suitable for the particular installation.

It is further recommended that the starter course of tiles be additionally fastened to theroof with a compatible construction adhesive to ensure weather tightness. With thestarter course installed, the first of tiles may be installed, starting with a full tile,extending 3/4" beyond the eaves and rakes in the prescribed manner using two (2) 1 screws per tile.


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It is recommended that a compatible construction adhesive be applied between the

starter course and the first course of tiles to ensure weather tightness.

Install the second course of tiles by cutting a tile in half vertically and install at theappropriate exposure. Alternate this with a full tile for the succeeding course over the

joints in the underlaying tile. The second and all remaining courses are fastened withtwo (2) 1 1/4" screws each." (Figure 8).

Install the roof tiles with 6" of exposure on most roof slopes. An exposure of greaterthan 6" but not exceeding 6 " may be used for roofs with a slope greater than 45.The exposure markings on the tile allow the exposure to be defined by the tile below.Do not install on roofs with a slope of less than 15 without first consulting with aqualified engineer.

Provide 1/8" - 1/4" gap between tiles in the same course to compensate for anymovement in the roof surface or expansion of the roofing tiles.


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FLASHING REQUIREMENTS

Most roof leaks occur where water is channeled off the roof or where the roof abuts avertical wall or chimney or where projections such as soil pipes pierce the roof structure.

At these points metal valleys saddle and flashings are used in conjunction with theroofing tiles to keep the structure dry.

Structural members that protrude through the roof should be flashed at all intersectingangles to prevent leakage. All base flashing should extend under the roofing tiles andup vertical surfaces and should be covered by a second layer of flashing (counterflashing).

Flashings should be stainless steel, copper or aluminum (as defined in the General

Construction Guideline section of this manual). The architect or contractor shouldensure that the selected flashing materials have the same longevity as the roofing tile.

VALLEYS

It is recommended but not required, that one ply of self-adhering membrane be installedin all valleys. The membrane should be extended 30" up the slope from the centerlineof the valley.


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Install the sheet metal valley flashing over the self-adhering membrane where applied.

The sheet metal flashing should extend not less than 12" up the slope from the valleycenterline. Cut and fit the tiles to provide a slight taper in the exposure in the exposureof the flashing toward the head (top) of the valley (Figure 9).

Overlap the sheet metal flashing sections a minimum of 4". All joints should be crimpedor sealed with a compatible construction adhesive to ensure weather tightness.

HIP DETAILS

It is recommended but not required, that one ply of self-adhering membrane be installedon all hip ridges prior to installing underlayment.

Intersecting roof sections at hips must be capped to ensure a weather tight roof joint.The Duratile hinged ridge cap is designed to accomplish this task. The 6" exposureincorporated into this unit matches the recommended roofing tile exposure creating avisually unified finished roof.

The roof tiles of each course are trimmed to the appropriate angle creating a finishedhip centerline. The tiles creating this intersecting joint should maintain a gap of 1/8"-1/4" between tiles to compensate for expansion and contraction.

Each course of intersecting tiles should be flashed at the joint to maintain weather

tightness. The flashing should be bedded in a compatible construction adhesive prior toinstalling the cap (Figure 10).


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Installation of the hinged cap will complete the hip construction. The hinge pin on theright hand cap should have a bead of sealant spread along the centerline prior to

installation.

Spread a bead of construction adhesive the full length of the roof course(Figure 11), approximately 4" on either side of the hip centerline and screw the hingedcap on the course with two (2) screws on each side. The screws for the cap installationmust be longer than the screws used on the roof tiles (1 3/4"long).

To complete the hip installation, spread a bead of color matched sealant the entirelength of the hip on the open side of the hinge.

RIDGE DETAILS

It is recommended but not required, that one ply of self-adhering membrane be installedon all ridges over the underlayment and extending down slope a minimum of 16" prior toinstalling the flashing.

Sheet metal flashing should be applied over the ridge prior to installing the ridge cap.The flashing should be bent to conform to the ridge angle and extend down either side


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from the centerline a minimum of 3"

It is recommended that a bead of compatible construction adhesive be applied parallelto the ridge and approximately 2 1/2" either side of the centerline of the ridge. Formaximum weather tightness it is desirable to spread a bead of compatible constructionadhesive under the final course of tiles at the ridge prior to fastening the tile with two (2)screws.

Installation of the ridge may now be completed by applying the hinged ridge cap.

Beginning at one end of the roof, install the first hinged cap with the tapered tail facingthe far end of the roof. The hinge pin on the right hand cap should have a bead ofsealant spread along the centerline prior to installation.

Spread a bead of construction adhesive the full length of the roof course (Figure 11),approximately 4" on either side of the hip centerline and fasten the hinged cap on thecourse with two (2) screws on each side. The screws for the cap installation must belonger than the screws used on the roof tiles (1 3/4" long).

Repeat this process for each successive ridge cap until the full ridge is completed. The

final cap should be trimmed to mate with the far roof rake taking care to ensure that onlythe slate textured portion of the cap is exposed.


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To complete the ridge installation, spread a bead of color matched sealant the entirelength of the ridge on the open side of the hinge.

RIDGE / HIP INTERSECTIONS

Roof styles which feature intersections of hips at the ridge of the roof require additionalcare to ensure weather tightness. In these instances, the installer should start the ridgeinstallation at the intersection point rather than at the open end of the ridge.

There are two (2) basic methods of creating a visually attractive and weather tightjuncture (Figure 13).

Both approaches will provide an acceptable closure for the intersection, though, theMitred approach requires more care to ensure a weather tight closure.

The lap joint is the easiest to construct and provides the most reliable weather seal.

For either type of intersection, follow the recommended procedures outlined in the hip

and ridge installation sections.


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CHANGES IN ROOF PITCH

There are many architectural styles which require changes in the roof pitch or require anintersection with a side wall. Each of these conditions poses a unique set ofrequirements to ensure weather tightness of the structure.

(Figures 14 - 17) illustrate recommended approaches to addressing these requirements.All these conditions require proper flashing and appropriate underlayment to circumventwater migration.

Whether these recommendations are followed is optional on part of the contractor.However, the contractor must follow accepted industry practices and ensure the buildingremains structurally sound and weather tight.


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PROJECTIONS AND PENETRATIONS

Many architectural styles incorporate projections from the roof line such as dormers,and almost all roof lines incorporate some form of penetration through the roof surface.

It is recommended but not required, that one ply of self-adhering membrane be installed

in conjunction with the required flashing for these applications. In projections such aschimneys and dormers, it is recommended that the membrane should be extended 4"-6"up any vertical wall.


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It is advisable to utilize a compatible construction adhesive as well as mechanicalfastening when installing the required flashing for these applications.

CHIMNEYS

Chimneys are constructed in different forms and locations depending on thearchitectural style of the building and local building practices.

(Figures 18-20), illustrate the most common styles and placement of the roof. Eachtype exhibits its own unique flashing requirements to ensure weather tightness.

All chimneys should be flashed on all four sides with the flashing extending up thevertical face of the chimney 6" and out onto the roof a minimum of 4". All base flashing

should have a headlap of 4" minimum and it is recommended that a constructionadhesive be used at all lap joints to minimize water penetration.

Counter flashing should be installed over the base flashing and the roofing tiles on thedown slope side of the chimney.

It is recommended that chimney saddles (Figure 20) be installed on chimneys where theupper side of the roof slope exceeds 30"

A minimum space 1/4" must be allowed between the vertical flashing face and theroofing tile courses to allow for expansion and contraction.

It is recommended that a compatible construction adhesive be used in conjunction withnails on each tile immediately abutting the chimney.Chimneys also tend to leak internally. It is the responsibility of the contractor to ensurethat the internal structure and flashings of the chimney weather tight and in good repair.


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DORMERS

Many architectural styles utilize dormers to add interior space and to provide visualinterest to the roof line.

It is recommended but not required, that one ply of self-adhering membrane be installed

in conjunction with the required flashing for these applications. In projections whichinclude vertical walls, it is recommended that the membrane should be extended 4"-6"up any vertical wall.


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Standard dormers (Figure 21) require flashing techniques common to both valleys and

wall intersections. Refer to these sections for approved construction details. The onlyunique flashing element is the counter flashing required on the downslope side of thedormer.

Recessed dormers (Figure 22) provide a more challenging set of flashing requirements.

In addition to the valley and sidewall intersections, the contractor must provide aweather tight floor and sidewalls for the recessed area of the dormer.

Typically the floors are formed from galvanized sheet steel, copper or aluminum. Theside walls must extend up the building structure a minimum of 6". All corners must be

welded, soldered or crimped and caulked in accordance with appropriate buildingcodes. The floor surface should have a downward slope of 1" per 12" of run.


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The bottom edge of the floor pan should extend downslope a minimum of 4" with thelower edge hemmed "

Additional counter flashing should extend out on the extended roof surface a minimumof 6" and downward to cover the vertical wall of the floor pan by 4".

NOTE: Current techniques utilizing rubberized continuous membranes may be used inplace of a sheet metal floor when locally available and comply with appropriate buildingcodes.

SKYLIGHTS

Skylights (Figure 23) are utilized in many buildings to bring additional natural light intothe interior of the building. Opening models also offer the additional benefit of providingventilation.

When installing skylights, the builder or contractor should select a pre- manufacturedunit of reputable quality and ensure that the unit is installed to the manufacturersspecifications.

Trim roof tiles neatly around the base of the flange allowing a minimum of 1/4"clearance for movement and secure to the roof with two (2) screws per tile.

It is recommended that a compatible construction adhesive be used in conjunction withthe screws to ensure weather tightness.


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ROOF VENTS

Very often roof vents (Figure 24), are required to improve air flow throughout thebuilding. A major function of roof vents is to remove heat build up in the roof peak andto remove condensation build-up in the upper portions of the building.

There are many styles of metal and plastic pre-manufactured roof vents available.When installing roof vents, the builder or contractor should select a pre- manufacturedunit of reputable quality and ensure that the unit is installed to the manufacturersspecifications.

Trim roof tiles neatly around the base of the flange allowing a minimum of 1/4"clearance for movement and secure to the roof with two (2) screws per tile.

It is recommended that a compatible construction adhesive be used in conjunction withthe nails to ensure weather tightness.

VENT STACKS

Vent stack and pipe flashings should consist of a self-flashing base with a friction fitelastomeric boot which seals the pipe and locks securely on the flange. When installingthe flange, the contractor should ensure that the flange extends 6" onto the roof surface


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and is secured in accordance with appropriate building codes.Trim roof tiles neatly around the base of the flange allowing a minimum of 1/4"

clearance for movement and secure to the roof with two (2) screws per tile.It is recommended that a compatible construction adhesive be used in conjunction withthe nails to ensure weather tightness.

CONTINUOUS RIDGE VENTS

Many buildings are constructed with pre-manufactured continuous ridge venting forimproved air flow in the structure.

There are basically two (2) styles of vents commonly in use today. The shingle overstyle (Figure 26), allows the hinged ridge cap to be installed directly over the ventingsystem. This type of vent minimizes the visual presence of the venting system as theroof appears to be of one material.

The second style of continuous vent is the filter vent type. This vent system is usually

manufactured from either metal or rigid plastic and is constructed with its own flashingas part of the vent system. The unit attaches directly over the roof ridge and takes theplace of the conventional ridge cap.


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Either type of venting system may be selected. The contractor should be familiar withthe selected venting system and ensure that the installation is carried out in accordance

with the manufacturers specifications and in compliance with the appropriate buildingcodes.

Duratile Inc.is confident that if the guidelines contained in this manual are followed,and that the installation is performed in a professional manner, your new DuratileRoofing Systemwill provide many years of trouble free use.

Not only will your roof be trouble free; the appearance of natural slate will increase thecurbside appearance of your home and improve its value in the ensuing years.

You are not only purchasing a high quality roof for your home, but investing in the future

well-being of your island.

duratile roofing system installation guide

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