ings at intersection of acoustical ceil- ings with change of material and/or vertical or oblique surfaces.
vii. If required mock-up and sound test panels of sufficient dimension to determine actual in place acoustical attenuation of the acoustical ceiling system. Method and supervision to be determined by the architect.
viii. Materials offered to meet speci- fied requirements or as substitution which do not have sufficient and/or recognised test data shall be required to be tested for acoustical absorbency and/or attenuation and/or vibration damping as directed by the architect and at this contractor's expense. The architect's decision shall be final.
ix. Acoustical adjustments to ceilings if necessary, during final testing and tuning period.
x. Supply all materials herein speci- fied to meet the outlined parameters acoustically for installation by other trades.
xi. Co-operation and co-ordination with work of other trades as required for the completion of the work fur- nished under this section.
xii. Repairing and/or replacement of damaged work caused by other trades. xiii. All hangers, supports and acces- sories not indicated on drawings or directly specified herein, but required for the proper and complete installa- tion of the acoustical treatment shall be supplied and installed as part of this section.
obviously should be adjusted to suit specific requirements. By defining the scope of the work carefully areas of doubt and duplication are reduced to a minimum.
(D) Tender documents:
Sample
(B) Mineral fibre lay-in panels:
Shall be as manufactured by the Celotex Corporation. Type 'Safetone Medium Density Acoustiform - mat'. i. Thickness shall be in.
Refer to item 2 (General conditions) ii. Units shall be 23% x 23% in., and of this section...
(E) Alternates:
Note that Alternate No(s) fect(s) the work..... etc.
4. SUBSTITUTIONS
as indicated on reflected ceiling plans. iii. Edges shall be fabricated uniform- af ly and true to fit suspension system. All finished surfaces shall be unbroken and unmarred.
(A) The materials or products speci- fied herein and indicated on drawings by trade names, manufacturer's name or catalogue number shall be provided as specified. Substitutions will not be permitted, except as described in Para- graph No..... of Section (General Conditions) (Supplementary Gen- eral Conditions) (Special Condi- tions).
5. ACCEPTABLE MANUFACTURERS (A) Except as otherwise specified herein or specially approved by the architect in writing, all acoustical treatment shall be products of one or more of the following manufacturers, subject to compliance with specifica- tion requirements:
-
iv. Unit surface shall be white, wash- able, factory applied finish that can be re-painted without loss of sound ab- sorbing efficiency. Ceiling shall have a light reflecting factor of at least 75%. v. Shall meet the following sound ab- sorption coefficients: 125/0.75; 250/0.75; 500/0.75; 1000/0.90; 2000/0.90; 4000/0.90 cycles/second (tolerance ±0.10)
11. MOCK-UP AND SOUND TEST (if required for testing non-rated mate- rials)
(A) Mock-up:
i. The mock-up shall consist of ap- proximately 300 sq. ft. of ceiling, and necessary partitioning to form two rooms.
ii. The location to be decided by the (B) Lay-in ceiling panels The Celo- architect, but will most likely be locat- tex Corp., etc.
ed on ground floor as indicated on
(C) Isolating hangers Johns-Mans- sketch. ville Corp., etc.
(D) Fibreglass and rockwool blankets xiv. Preparation of shop drawings (if and/or batts - Owens-Corning Fiber-
required).
xv. Samples and manufacturers data. xvi. Compliance with standard and industry specifications.
xvii. Cleaning of all work after work of other trades is complete.
(C) Work not included:
i. Plaster ceilings.
ii. Acoustical structural floors and roofs.
glass Corp., etc. (E) Perforated panelling Insulation ('Silenply'), etc.
6. SHOP DRAWINGS
iii. The ceiling system shall include
..etc.
12. INSTALLATION
Bradford (A) General notes:
(A) Submit .... copies of show draw- ings....
7. SAMPLES AND MANUFACTUR- ERS' DATA
i. This contractor shall examine all surfaces, services, constructions, to which his materials are to be applied, should any appear unsuitable, notify the architect. Commencement of in- stallation of materials under this sec- tion will be taken as acceptance of the conditions by this contractor.
iii. Wall and ceiling wood and metal (A) Prior to fabrication or delivery ii. Acoustical units shall be centred in furring.
iv. Acoustical door systems. v. Canvas connections, ductwork, lining and wrapping of ducts for both air-conditioning and electrical trunking and cable tray work.
vi. Electrical lighting (and fixture support to structure).
vii. Air diffusers and air return grilles. viii. Insulation except as specified for acoustical system.
ix. All trim, moulding, painting, plas- tering, screeds, grounds and stops for plastering concrete and masonry work and finish floor materials (other than carpeting).
The foregoing is a sample only and
submit samples....
8. COMPLIANCE WITH STANDARD AND INDUSTRY SPECIFICATIONS
(A) Any materials or operations speci- fied by reference. ...
9. CO-OPERATION ORDINATION
AND CO-
(A) Co-operation and co-ordination with the work of other trades....
10. MATERIALS
(A) General notes:
Acoustical units shall be delivered to project site in manufacturer's pack ages with seals unbroken...
rooms and spaces in which they are to be installed or as laid out in the re- flected ceiling plans. Consult the ar- chitect and obtain this approval, prior to any installation of the work. Etc., etc.
13. CLEANING
(A) Following installation. . . .
PRICING
14. SEPARATE UNIT PRICING
(A) General notes:
AND
i. This contractor shall submit separ- ate pricing including overhead, profit and overall expense, items required to complete the work.
32
Far East BUILDER, August 1970