TESTING APPLICATION STANDARD (TAS) 116-95
TEST PROCEDURE FOR AIR PERMEABILITY TESTING OF
RIGID, DISCONTINUOUS ROOF SYSTEMS
Scope 2.S Roof Consultants Institute
Glossary of Terms
1.1 This Protocol covers the determination of the
air permeability characteristics of arigid,dis- Terminology & Units
continuous roof system.
3.1 Definitions - For definitions of terms in this
1.2 The test procedures outlined herein shall be Protocol, refer to Chapter 2 and Section 1513
used to determine the air pressure difference of the Florida Building Code, Building and/or
(DP) and the air volume flow rate (Q) which the RCI Glossary of Terms. Definitions from
occur acrosstherigid,discontinuous roof sys- the Florida Building Code, Building shall take
tem when the air flow rate into a sealed cham- precedence.
ber beneath the system is such that the
moment incurred on the rigid components 3.2 Units - For conversion of U.S. customary
within the system is equal to 90% of the units to SI units, refer to ASTM E 380.
restoring moment due to gravity (Mg ) of the
rigid components. Significance and Use
1.3 The calculations outlined herein shall be used 4.1 Use of this Protocol is limited to manufactur-
to determine the air permeability (Cd) for the ers of rigid, discontinuous roof systems who
desire to have their system(s) tested for wind
system being tested.
characteristics in compliance with TAS 108.
This limitstheProtocol's use to discontinuous
1.4 All testing and calculations shall be conduct-
roof system in which the unsealed, overlap-
ed by an approved testing agency and all test
ping, rigid components have a length between
reports, including calculations, shall be signed
1.0 and 1.7S feet; an exposed width between
by a Professional Engineer or Registered Roof
0.73 and 1.2S feet; and a thickness not greater
than 1.3 in.
4.2 The procedures and calculations outlined
herein provide a means of determining the air
2.1 The Florida Building Code, Building.
permeability (Cd ) for a rigid, discontinuous
roof system. This value shall be listed in the
2.2 Application Standards
system manufacturer's Roof System
TAS 108 Test Procedure for Wind Tunnel Assembly Product Control Approval for refer-
Testing of Air Permeable, Rigid, ence by the Chief Code Compliance Officer to
Discontinuous Roof Systems determine whether the system is air permeable
or air impermeable. The Chief Code
2.3 The British Standard BS5534 - Appendix Compliance Officer may nullify this testing
A.5.1. requirement for systems which are generally
Method of Test for the Air Permeability considered air permeable.
Factor D of Unsealed Small Element Roof
Assemblies 4.3 The test criteria will be based on testing,
under the provisions of this Protocol, of rigid,
2.4 ASTM Standards prepared roof coverings which are generally
E 380 Excerpts from the Standard Practice considered air impermeable (i.e. metal roof
for Use of the International System systems, and lap sealed, rigid prepared roof
of Units (SI) (the Modernized coverings). This criteria shall be determined
Metric System) by September 1, 1994. Until that date, the
FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ (TAS) 116-95.1
(TAS) No. 116-95
Chief Code Compliance Officer shall judge as lish appropriate safety and health practices
to whether a prepared roof covering is air per- and determine the applicability of regulatory
meable or air impermeable. limitations prior to use.
Apparatus Apparatus Checks - the following steps shall be
conducted prior to any air permeability testing.
5.1 The pressure from beneath the system shall be
generated in a sealed, rectangular plenum 7.1 The pressure tube from the plenum chamber
chamber having a depth not less than 2 feet. to the manometer device shall be checked for
The chamber shall be airtight with the excep- leakage by applying a constant pressure with-
tion of an open upper face; a tapping for a in the tube and clamping it off. Leakage shall
pressure tube; and an air inlet pipe. The cham- be identified by any pressure drop recorded by
ber shall be of sufficient dimensions to a pressure measuring device. Any pressure
receive a wood deck on which the minimum tube which exhibits leakage shall be repaired
number of rigid components, noted in Section or replaced.
8.5, shall be installed. (See Figure 1,
attached.) 7.2 The manometer, if utilized, shall be cross-
checked against an electrical pressure trans-
5.2 The pressure tapping, noted in Section 5.1, ducer.
shall be positioned on the chamber so as to
avoid direct alignment with the air inlet pipe. 7.3 Airtightness Check
The pressure tube shall be connected to a
manometer or an electrical pressure transduc- 7.3.1 Close the top of the plenum chamber
er to measure the pressure within the chamber by attaching and sealing the edges of
relative to that outside the chamber. The pres- the cover panel so that the plenum
sure tapping shall be fully sealed around the chamber is air tight with the exception
pressure tube. of the inlet pipe.
5.3 The air inlet pipe shall be connected to an 7.3.2 Supply air from the electric fan
electric fan which is capable of producing a through the inlet pipe to induce a pres-
continuous air volume flow of 7 ft3/s through sure difference between the inside and
the air inlet pipe. The connection between the outside of the plenum chamber of not
air inlet pipe and the chamber shall be fully less than 10.5 lbf/ft2.
sealed around the perimeter of the air inlet
pipe. The air inlet pipe shall be equipped with 7.3.3 If this pressure can be maintained for a
an air flow meter capable of measuring an air period of 1 minute with an air pressure
volume flow rate (Q) of not less than 9.0 ft3/s flow rate not greater than 0.2 ft3/s, the
and having an accuracy of 0.1 ft3/s. airtightness shall be considered satis-
5.4 An airtight removable cover panel shall be
used to check the air tightness of the plenum
chamber, as noted in Section 5.3.
5.5 A weighing device with an accuracy of 0.05 lb
shall be used to determine the average mass of
8.1.1 The substrate shall consist of APA
the rigid components which make up the pre-
32/16 span rated sheathing of 15 / 32 in.
pared roof covering.
thickness, attached with 8d common
nails at 6 in. o.c. at panel edges and 12
in. o.c. at intermediate supports, and
an underlayment. The underlayment
6.1 This Protocol may involve hazardous materi-
shall consist of a No. 30 ASTM D 226,
als, operations and equipment. This Protocol
type II asphalt saturated anchor sheet,
does not purport to address all of the safety
mechanically attached to the sheathing
problems associated with its use. It is the
with approved nails and tin caps
responsibility of the user to consult and estab-
(TAS) 116-95.2 FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ
(TAS) No. 116-95
spaced in a 12 in. grid staggered in two lished installation instructions.
rows in the field and 6 in. o.c. at laps. Minimum nails shall be 12 ga. ring
Over the anchor sheet, one layer shank, hot dipped galvanized roofing
ASTM D 249 mineral surfaced cap nails. Minimum screws shall be #8
sheet shall be applied in a full mopping diameter screw fasteners.
of ASTM D 312, type IV asphalt. Side
laps (if any) shall be 6 in. and head 8.5 Battens (if applicable)
laps (if any) shall be 2 in., nailed 12 in.
o.c. and 6 in. o.c, respectively. 8.5.1 Horizontal Batten System
8.1.2 The substrate, consisting of the wood • Horizontal battens shall be of
deck and the underlayment, shall have nominal 1in.x 2 in. dimensional lum-
3 in. holes spaced 6 in. across its width ber and shall be spaced to provide
in staggered rows spaced 6 in. along its a minimum 3 in. head lap, or to
length to allow for airflow into the sys- match the interlocking configura-
tem. tion of the component's profile.
8.1.3 The substrate perimeter shall be com- • Horizontal battens shall be nailed
pletely sealed when placed in the to the wood test deck at 6 in. o.c.
plenum chamber. using 12 ga. roofing nails.
8.2 Mortar (if a mortar set tile system assembly) 8.5.2 Counter Batten System
8.2.1 Mortar mix shall have a Roofing • Vertical battens shall be of
Component Product Control Approval nominal 1 in. x 4 in. lumber and shall
for use with the mortar set tile system be spaced 24 in. over the intermedi-
and shall be in compliance with TAS ate supports (trusses).
• Vertical battens shall be nailed to
8.2.2 Mortar shall be mixed using the mix- the wood test deck at 6 in. o.c. using
ing ratio specified in the mortar manu- 12 ga. roofing nails.
facturer's Product Control Approval.
• Horizontal battens (counter
8.2.3 Mortar flow shall be determined using battens) shall be as noted in
a cone penetrometer test, in compli- Section 8.5.1, nailedtothe 1 in. x 4 in.
ance with ASTM C 780 (Appendix vertical battens using 12 ga.
Al), the results of which shall be 21/8 roofing nails of sufficient length
+ 1/8 in. (55 ± 3 mm) of penetration. to penetrate both battens.
8.3 Adhesive (if an adhesive set tile system 8.5.3 If the system being tested is installed
assembly) over battens, the battens shall be
installed prior to drilling the 3 in. holes
8.3.1 Adhesive shall have a Roofing noted in Section 8.1.2.
Component Product Control Approval
8.6 Rigid Components
for use with the adhesive set tile sys-
tem which is being tested and shall be
8.6.1 Rigid components shall meet the size
applied in compliance with the provi-
requirements listed in Section 4.1.
sions set forth in that Approval.
8.6.2 Rigid components shall be attached or
8.4 Fasteners (if applicable)
bonded in compliance with the system
manufacturer's published installation
8.4.1 Component attachment fasteners (i.e., instructions and the minimum require-
nails, screws, tile straps, etc.) shall be ments of the Florida Building Code,
those recommended in the prepared Building. For mechanically attached,
roof covering manufacturer's pub- direct deck applications, care shall be
FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ (TAS) 116-95.3
(TAS) No. 116-95
taken so as to avoid direct alignment of
the fastening line for each course with where
the staggered rows of 3 in. holes in the
substrate, noted in Section 7.1.2. For W = average component weight (lbf);
mortar or adhesive applications, care m = average component mass (lbm); and,
shall be taken to avoid mortar or adhe- g = 32.2 ft/s2 = acceleration of
sive application over these holes. If gravity constant.
this is unavoidable due to the configu-
ration/spacing of the rigid components Note: 1 slug = 1 lbf s2/ft
within the system, the holes shall be
cleared of excess mortar or adhesive 9.1.3 Determine the restoring moment due
prior to the material hardening.
to gravity (M g ) from the center of the
exposed area about the head of the
8.6.3 The number of rigid components to be rigid component using the compo-
installed on the substrate, unsealed, nent's average weight and the follow-
shall be in compliance with Table 1, ing equation.
Mg= W x l where,
NUMBER OF COURSES AND NUMBER OF COMPONENTS
PER COURSE M g = restoring moment due to gravity
Component Minimum Number of Minimum Number per (ft-lbf);
Type Courses Course W = average component weight (lbf); and
Single Lap 2 2 1 = moment arm (ft) (distance from center
Plain Tiles (bonded or 2 4 of exposed area to the head of the
mechanically attached) component)
Slates 2 2
9.2 Pressure to Induce Moment (p)
8.6.4 In addition to the number of compo-
nents listed in Table 1, a sufficient 9.2.1 Determine the upward pressure
number of components shall be pro- required to induce the restoring
vided to cover the perimeter area of the moment due to gravity, determined
substrate. These components shall be above, using the following equation.
completely sealed at all laps, front and
side joints with approved adhesive. where,
9. Preliminary Measurements and Calculations
p = pressure required to induct moment
9.1 Average Mass, Weight and Restoring Moment
due to Gravity (Mg) (lbf/ft2);
Mg = restoring moment due to gravity
9.1.1 Determine the mass of eachrigidcom- (ft-lbf);
ponent to be installed and calculate the b = component cover width (ft);
average mass. 1o = component exposed length (ft)
= total length - headlap dimension; and
9.1.2 Determine the average weight of the 1 = moment arm (ft) (distance from
rigid components using the average center of exposed area to the head of
mass and the following equation. the component)
9.3 Effective Area (a)
9.3.1 Determine the effective area (a) (i.e.,
the area having unsealed components)
across which the pressure difference
will occur using the following equa-
(TAS) 116-95.4 FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ
(TAS) No. 116-95
a = Nxbx lo where, 12. Report
a = effective area (ft2); 12.1 The final test report shall include the follow
N = number of unsealed components; ing:
b = component cover width (ft); and
1o = component exposed length (ft) 12.1.1 The type, name, and manufacturer of
the discontinuous roof system and the
= total length - headlap dimension
dimensions of the rigid components
within the system.
10. Test Procedure
12.1.2 A detailed report of the system instal
10.1 Position the test specimen in the plenum
lation prepared by a Professional
chamber, insuring that born the substrate
Engineer or Registered Roof
perimeter and the perimeter rigid components
Consultant, including a sketch of the
are completely sealed.
installed system, indicating the sealed
and unsealed components, and the
10.2 Supply air through the inlet pipe to the
published installation instructions pro
plenum chamber, gradually increasing the air vided by the system manufacturer.
flow until the manometer indicates a pressure
difference (ΔP) equal to 90% of the pressure
12.1.3 Data and calculations for average mass
(p) determined in Section 9.2.
(m); average weight (W); restoring
10.3 When the pressure difference (ΔP) reaches moment due to gravity (Mg); pressure
this point, record the pressure difference (ΔP) required to induce moment (p); and
and the air volume flow rate (Q) and gradual effective area (a).
ly reduce the air supply to zero.
12.1.4 Pressure difference (ΔP) and air vol
10.4 Repeat this test procedure three times using ume flow rate (Q) readings at the point
the same test specimen. If any evidence of when the pressure needed to incur
damage exists subsequent to any test, con moment is attained.
struct an additional test specimen for the addi
tional test(s). 12.1.5 Calculations and results for the air per
meability (Cd) of the three tests and
11. Calculations the average value.
11.1 Determine the air permeability (Cd) using
information gathered from preliminary calcu
lations, testing procedures and the following
Cd = air permeability (dimensionless);
Q = air volume flow rate (ft3/s);
a = effective area (ft2);
ΔP = pressure difference (lbf/ft2); and
ρ = density of air = 2.377 x 10-3
11.2 Determine the average air permeability for the
three tests conducted.
FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ (TAS) 116-95.5
(TAS) No. 116-95
AIR PERMEABILITY TEST APPARATUS
(TAS) 116-95.6 FLORIDA BUILDING CODE — TEST PROTOCOL HVHZ