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- SECTION 07615
-
- PROTECTED LEAD MEMBRANE ROOFING
- NOTE ** This section is based on products manufactured by
- members of the Lead Industries Association, Inc.,
- at the following address:
- NOTE ** 295 Madison Avenue
- NOTE ** New York, NY 10017
- NOTE ** Telephone 212-578-4750
- NOTE ** Fax 212-684-7714
- NOTE **
- NOTE ** Lead waterproofing has long been used for plazas,
- fountains, pools, and other applications on
- outstanding buildings such as the World Trade
- Center and the United Nations Library.
- NOTE **
- NOTE ** Now, in combination with extruded polystyrene
- insulation panels, flat roofs with impressive
- lifetime-cycle performance are being constructed.
- NOTE **
- NOTE ** SECTION 07615 - PROTECTED LEAD MEMBRANE ROOFING,
- Copyright 1996, The Architect's Catalog, Inc.
-
-
- PART 1 GENERAL
-
- 1.1 SECTION INCLUDES
- NOTE ** Delete items below not required for project.
-
- A. Continuous, welded lead sheet membrane roofing.
-
- B. Insulation.
-
- C. Insulation ballast.
-
- D. Counterflashings for lead roofing.
-
- E. Penetration flashings and perimeter flashings for lead
- roofing.
-
- 1.2 RELATED SECTIONS
- NOTE ** Delete any sections below not relevant to this
- project; add others as required.
-
- A. Section 03300 - Cast-In-Place Concrete.
-
- B. Section 06100 - Rough Carpentry.
-
- C. Section 07152 - Lead Membrane Waterproofing.
-
- D. Section 07600 - Flashing and Sheet Metal.
-
- 1.3 REFERENCES
- NOTE ** Delete references from the list below that are not
- actually required by the text of the edited
- section.
-
- A. ASTM A 167 - Standard Specification for Stainless and
- Heat-Resisting Chromium Nickel Steel Plate, Sheet, and
- Strip.
-
- B. ASTM A 666 - Standard Specification for Austenitic
- Stainless Steel, Sheet, Strip, Plate, and Flat Bar.
-
- C. ASTM B 749 - Standard Specification for Lead and Lead
- Alloy Strip, Sheet, and Plate Products.
-
- D. ASTM C 578 - Standard Specification for Rigid, Cellular
- Polystyrene Thermal Insulation.
-
- E. ASTM D 226 - Standard Specification for Asphalt Saturated
- Organic Felt Used in Roofing and Waterproofing.
-
- F. Flat Roofing Brochure - Lead Industries Association, Inc.
- (LIA).
-
- 1.4 SUBMITTALS
-
- A. Submit under provisions of Section 01300.
-
- B. Product Data: Provide manufacturer's standard details
- and catalog data demonstrating compliance with referenced
- standards. Provide installation instructions.
-
- C. Samples:
- 1. 6 x 6 inch samples of sheet lead.
- 2. Samples of insulation board.
- 3. Ballast samples.
- 4. Stainless steel strip for insulation ballasting.
-
- 1.5 QUALITY ASSURANCE
-
- A. Installer Qualifications: Employ only qualified
- journeymen lead burners to join sheets of lead.
-
- 1.6 DELIVERY, STORAGE, AND HANDLING
-
- A. Handle, store, and protect lead from deformation,
- construction traffic, and damage.
-
- B. Handle, store and protect insulation in accordance with
- manufacturer's instructions.
-
-
- PART 2 PRODUCTS
-
- 2.1 MEMBRANE MATERIALS
-
- A. Sheet Lead:
- 1. Comply with ASTM B 749.
- 2. Weight: 5 psf (5/64-inch thick) minimum.
- 3. Furnish in 8 x 25 foot rolls, unless otherwise
- required or approved.
-
- B. Burning Rods: Same composition as sheet lead.
-
- C. Underlayment: 15 lb. asphalt-impregnated felt; ASTM D
- 226, Type I.
-
- D. Slip Sheet: Reinforced plastic or paper such as "Tyvek,"
- "Visquine," etc.
-
- E. Temporary Protection Board: At least one, 1/2-inch thick
- layer of any suitable particle board or plywood.
-
- 2.2 COUNTERFLASHING MATERIALS
- NOTE ** Delete 1 of the 2 following paragraphs, and edit
- gage to suit project conditions.
-
- A. Stainless Steel: ASTM A 167, Type 304, 28 gage unless
- otherwise indicated.
-
- B. Lead-Coated Stainless Steel: ASTM A 167, Type 304, 28
- gage prior to coating unless otherwise indicated.
-
- 2.3 INSULATION MATERIALS
-
- A. Insulation: Extruded polystyrene, ASTM C 578, Type VI.
- B. Compressive strength: 40 psi minimum.
- 1. Tongue and grooved edges on two sides.
- 2. Drainage channels on surface in contact with roofing
- membrane.
- NOTE ** Edit the 3 following paragraphs to suit project
- requirements.
- NOTE **
- NOTE ** Either single or double-layer installation may be
- employed. In double-layer systems, bottom layer
- thickness must be at least 2 inches thick, and must
- be the thicker of the two layers.
- NOTE **
- NOTE ** Select thickness to provide an R-value that will
- maintain the lead membrane at a near constant
- temperature (R-15 minimum).
- NOTE **
- NOTE ** See foam manufacturer's literature for additional
- thicknesses available.
- 3. Bottom layer foam thickness: 2 inches.
- 4. Top layer foam thickness: 1-1/2 inches.
- 5. Foam thickness: 3 inches.
- NOTE ** Foam insulation must be protected from U.V.
- exposure and secured against wind uplift by 1 of 4
- accepted methods, which are:
- NOTE ** - Foam panels with integral factory-facing of
- cement mortar.
- NOTE ** - Placing stone ballast on top of foam.
- NOTE ** - Placing roofing pavers on top of foam.
- NOTE ** - A combination of roofing pavers (at perimeters
- and as walkways) with
- NOTE ** stone ballast over remainder.
- NOTE **
- NOTE ** Insulation with integral factory-facing of cement
- mortar is generally restrained at perimeters and
- penetrations by stainless steel straps and
- securement devices or by roofing pavers and relies
- upon tongue and groove edges to prevent uplift of
- field boards.
- NOTE **
- NOTE ** Delete the following paragraph if insulation with
- integral facing of cement-mortar is not required.
- 6. Integral mortar facing: Latex-modified Portland
- cement mortar weighing 4.5 psf.
- a. Facing thickness: 3/8 inch mortar facing (in
- addition to foam thickness).
- NOTE ** Delete the following paragraphs, including
- separation sheet, if stone or paver ballast
- materials are not required.
- NOTE **
- NOTE ** If used, edit to suit project requirements.
-
- C. Separation Sheet: As recommended by insulation
- manufacturer.
-
- D. Ballast:
- 1. Aggregate: Sound, hard, durable stone; ASTM D 448,
- No. 4, free of dirt, debris, and other deleterious
- matter.
- 2. Select aggregate: As above, except screened to 1
- inch minimum to 1-1/2 inch maximum.
- NOTE ** A variety of additional paver designs are
- available. Those specified below have been
- selected primarily for use as walkways and
- perimeter securement of aggregate ballasted
- installations, and for perimeter securement of
- mortar-faced foam installations. See foam and
- paver manufacturer's literature for additional
- requirements and design criteria.
- NOTE **
- NOTE ** For designs with full coverage with pavers, see
- foam manufacturer's recommendations for air space
- between foam and pedestals.
- 3. Pavers: Normal weight concrete paver units
- manufactured for use as roof ballast.
- a. Weight: At least 15 psf.
- b. Compressive strength: At least 7,500 psi.
- NOTE ** Specify color, below, or delete if immaterial.
- c. Color: _______________.
- NOTE ** Edit size, below, to suit project requirements, or
- delete entirely other applications where size is
- immaterial.
- d. Size: 24 x 24 inches.
- e. Size: 18 x 18 inches.
- f. Size: 12 x 18 inches.
- g. Size: 12 x 12 inches.
-
- 2.4 MISCELLANEOUS MATERIALS
- NOTE ** Delete 1 of the 2 following paragraphs.
-
- A. Cants: Concrete cants specified in Division 3.
-
- B. Cants: Pressure-preservative-treated wood specified in
- Division 6.
- NOTE ** A variety of metal securement devices are available
- for mortar-faced insulation units. Consult
- manufacturer's literature.
- NOTE **
- NOTE ** Delete the following paragraph if not required.
-
- C. Insulation Securement: ASTM A 666 stainless steel straps
- and securement devices, as recommended by insulation
- manufacturer.
-
-
- PART 3 EXECUTION
-
- 3.1 EXAMINATION
-
- A. Examine surfaces to receive sheet lead roofing.
- 1. Verify that surfaces are smooth and even, free of
- projections, protrusions, or other irregularities.
- 2. Verify that angles and edges over which lead will be
- turned are chamfered or eased.
- 3. Verify that cants are securely installed.
- 4. Do not begin roofing operations until surrounding or
- abutting construction and penetrations through
- roofing are completed and approved.
- NOTE ** Delete the following paragraph if concrete roof
- deck is not used.
- NOTE **
- NOTE ** When retrofitting lead roofing over existing
- substrates, an additional underlayment surface such
- as gypsum board or plywood may be necessary, and
- should be included in this or another specification
- section.
-
- B. Cementitious Substrates:
- 1. Verify that concrete is sound, clean, and free of
- dirt, dust, debris, or other contaminants.
- 2. Verify that concrete surfaces have been screeded and
- floated to a smooth surface without projecting stones
- or other aggregate.
- 3. Verify that brick or other masonry substrates are
- laid true and straight, with joints struck flush or
- tooled with half-round tool.
-
- C. Notify the Architect in writing of any defective
- conditions encountered.
-
- D. Correct defective conditions before beginning
- waterproofing work. Starting of work shall constitute
- acceptance of such conditions.
-
- 3.2 SURFACE PREPARATION
- NOTE ** Delete the 3 following paragraphs if cementitious
- substrates are not used.
-
- A. Grind down high spots.
-
- B. Fill low spots with Portland-cement-based patching
- compound approved by the Architect.
-
- C. Parge irregular substrates with acrylic-latex modified
- Portland-cement-based mortar approved by the Architect.
-
- D. Install 1 layer of underlayment over entire surface to be
- waterproofed. Install 1 layer of slip sheet over
- underlayment.
-
- 3.3 MEMBRANE INSTALLATION
-
- A. Lay out sheet to minimize joints.
-
- B. Lap joints between adjoining sheets 1-1/2 inches minimum.
-
- C. Tools, brakes, tongs, etc., shall be such as to bend and
- work lead to easy curves and to prevent scoring or
- damaging the material. Only proper lead working tools
- (wooden mallets, dressers, etc). are acceptable to form
- the lead.
-
- D. Allow room for expansion between rigid members.
-
- 3.4 JOINTS
-
- A. Clean by shave hook, lead scraper, or wire brush,
- sections of lead that are to become a part of the joint.
-
- B. Join adjacent pieces of lead sheet by burning (welding of
- lead to lead).
- 1. Use only the smallest size tip on burning torch.
- 2. Use only hydrogen and oxygen gases only.
- 3. Take extreme care to avoid burning through or
- reducing the thickness of the lead sheet being
- joined.
-
- 3.5 FLASHINGS
-
- A. Install lead sheet base flashings integrally with roofing
- membrane.
- 1. Extend to top of and across parapets, unless
- otherwise indicated.
- 2. Where membrane terminates at vertical walls,
- terminate flashing in reglet.
-
- B. Install stainless steel counterflashings as indicated.
-
- C. At penetrations, install lead sheet flashings and burn
- same to membrane.
- 1. Comply with details and recommendations of LIA Flat
- Roofing Brochure, unless otherwise indicated.
-
- 3.6 INSULATION
-
- A. Install insulation in accordance with insulation
- manufacturer's instructions for protected membrane
- roofing.
-
- B. Cut neatly to fit around projections and penetrations and
- at perimeter.
- NOTE ** Delete 1 of the 2 following paragraphs when mortar-
- faced insulation is used.
- NOTE **
- NOTE ** Delete both if mortar-faced insulation is not used.
-
- C. Secure perimeters of and penetrations through mortar-
- faced insulation with pavers.
-
- D. Mechanically fasten mortar-faced insulation with
- stainless steel securement devices in accordance with
- manufacturer's instructions.
- NOTE ** Delete the following article if insulation with
- integral mortar facing is used exclusively.
-
- 3.7 BALLAST
-
- A. Install separation sheet in accordance with insulation
- manufacturer's instructions.
- NOTE ** Delete one or both of the following paragraphs, as
- required by project conditions.
-
- B. Install roof pavers over entire surface. Cut neatly to
- fit around projections and penetrations and at perimeter.
-
- C. Install roof pavers in the locations indicated on the
- drawings. Cut neatly to fit around projections and
- penetrations and at perimeter.
- NOTE ** Delete the following paragraph if aggregate ballast
- is not used.
- NOTE **
- NOTE ** Aggregate rate is dependent upon aggregate size,
- building height, and wind conditions. Consult foam
- manufacturer's literature for additional
- information, and edit the following paragraphs to
- suit project conditions.
-
- D. Install aggregate ballast at the rate so as to ensure
- complete coverage of foam, and blockage of U.V. light.
- 1. Use at least 10 pounds of aggregate per square foot.
- 2. Within 4 feet of perimeter, penetrations, and drains,
- use at least 20 pounds of aggregate per square foot.
- 3. Use select aggregate around drains.
-
- 3.8 PROTECTION
-
- A. Protect material and work in place from damage. Repair
- any damage that may occur.
-
- B. Provide temporary water cut-offs to prevent penetration
- of water underneath the membrane when work is
- interrupted, at end of day, or during inclement weather.
- Remove and discard temporary cut-offs before proceeding.
-
- C. Temporary Protection: Do not permit construction traffic
- directly on top of lead sheet. Install suitable
- protection board as installation proceeds to guard
- against occasional, essential light traffic and against
- excessive temperature changes until permanent covering
- has been installed.
-
-
- END OF SECTION
-