home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Spec Disk 1998 Spring 4.0
/
Spec Disk 1998 Spring 4.0.iso
/
text
/
07615lia.txt
< prev
next >
Wrap
Text File
|
1998-06-10
|
15KB
|
411 lines
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