Section Cover Page
Section 260540
Underfloor Duct System
2010-11-01for Electrical Systems

This Master Specification Section contains:

.1This Cover Sheet

.2Specification Section Text:

1.General

1.1Related Requirements

1.2System

1.3Shop Drawings

1.4Delivery, Storage and Handling

2.Products

2.1Duct

2.2Inserts

2.3Junction Boxes

2.4FeedIn Ducts

2.5AC Outlets

2.6Telephone and Low Tension Outlets

3.Execution

3.1Duct Installation

3.2Installation of Coverpans

3.3Installation of Box Sleeves

3.4Installation of Conduit Feeders

3.5Installation of Duct Markers

3.6Installation of Outlets

BMS Basic Master Specification
Alberta Infrastructure
Master Specification System / Page 0
Section 260540
Underfloor Duct System
Plan No:for Electrical Systems
Project ID:Page 1

1.General

1.1RELATED REQUIREMENTS

.1Submittal Procedures:Section013300.

.2LEED Requirements:Section013518.

.3Waste Management and Disposal:Section017419.

.4Metal floor deck:Section053000.

.5Electrical General Requirements:Section260010.

1.2SYSTEM

.1This section includes for underfloor duct systems, complete with all closure pieces, couplings, junction fittings, adaptors, wall elbows, etc., required for a complete installation.

.2Duct system:[two] [three] duct system, [one] [two] [three] for 120 V ac and [one] [two] [three] for telephone and/or low tension wiring.

1.3SHOP DRAWINGS

.1Comply with requirements of Section 260010.

.2Clearly indicate, by large scale details, all conditions of construction, plug layout, joints and accessories, dimensions, finishes and related work.

1.4DELIVERY, STORAGE AND HANDLING

.1Separate waste materials for [reuse] [and] [recycling] in accordance with Section 017419 Waste Management and Disposal.

2.Products

2.1DUCT

.1Duct:1.9mm steel, corrosionresistant finish. Nominal dimensions of ac Duct [38mmx76mm] [38mmx152mm] with cross sectional area not less than [2130mm2] [5160mm2. Nominal dimensions of telephone and low tension duct [38mmx76mm] [38mmx152mm] with cross sectional area not less than [2130mm2] [5160mm2].

.2Flush duct:1.9mm steel with corrosionresistant finish. Nominal dimensions of flush duct 38mmx76mm with cross sectional area not less than 2130mm2. [Provide double or triple duct systems as indicated. Flush duct furnished with five precut 32mm diameter holes per 3000mm length, on 600mm centres and closed with flat, metal screw plugs.

.3Trench duct:1.9mm steel []mm deepx[]mm wide with corrosionresistant finish, 6mm thick steel removable coverplates with overlapping fully gasketted joints. Trench duct to have [] compartments, []mm wide for low tension. Telephone compartment to have [] openings on [] centres. Sound compartments to have [] openings on [] centres. [Compartments to have openings as indicated on the drawings.]Field cut all openings with hole saw and bush hole with polyethylene snap ring or grommet. Construct trench duct with cross bars or straps, permitting free layin of cables, levelling screws to permit upward adjustment before or after concrete pour and adjustable compartment dividers of 1.9mm steel.

2.2INSERTS

.1Inserts:[] high, 50mm diameter with internal thread for 50mm pipe.

.2Feedin duct to be blank.

.3Use [preset] [afterset] inserts.

2.3JUNCTION BOXES

.1Junction boxes complete with modifications shown on drawings and as required for the system; with internal barriers, facilities for feedin conduit, levelling screws, coverplates and collars and/or extension rings to suit depth of duct installation below top of finished floor. Coverpans of overlapping stainless steel type with flush head stainless steel holding studs.

2.4FEED-IN DUCTS

.1Blank duct with nominal dimensions of [38mmx76mm] [38mmx152mm] 50mm below top of finished floor, complete with vertical elbows, duct extension, panel box connectors and offsets.

2.5AC OUTLETS

.1Outlet housing of cast [stainless steel] [aluminum] construction, fitting tightly to the floor and 76mm high maximum, complete with mounting base, insert adaptor, locking nipple and receptacle.

2.6TELEPHONE AND LOW TENSION OUTLETS

.1Outlets of matching design to ac outlets, complete with single faced one hole bushed stainless steel cover.

3.Execution

3.1DUCT INSTALLATION

.1Install underfloor duct flush with top of concrete base slab with provision for []mm of topping. Excepting feedin ducts, install duct with tops of preset inserts 3mm below floor line. Locate inserts on []mm centres.

.2Install flush duct, flush with finished floor.

.3Install trench duct trim, with surface flush with coverplates, covered with factory applied tape for protection.

.4Support duct on 1500mm centres and no more than 300mm from ends of duct on adjustable duct supports which clamp each duct into position and secure to prevent floating.

.5Supervise all concrete placement around ducts to ensure concrete forms a solid base under duct, free from voids.

3.2INSTALLATION OF COVERPANS

.1Install boxes complete with coverpans to receive floor covering.

.2Coordinate installation of tile or floor covering over pans.

.3Supply junction boxes in carpeted areas with coverplates only.

3.3INSTALLATION OF BOX SLEEVES

.1Punch knockouts in junction boxes in bottom plate, [one] [two] in the telephone and low tension section, and [one] [two] in the ac section. Punch knockouts in from the bottom to permit later removal from the top. Drill 3mm hole in centre of knockout. Below each knockout, install styrofoam sleeve or plug running from the underside of knockout to slab form. Nail styrofoam plug through nail hole to form work.

.2When using cast bottom box, provide hole with removable snap out plug with 3mm hole in centre of plug in lieu of knockout specified above.

3.4INSTALLATION OF CONDUIT FEEDERS

.1Provide conduit feeders from [telephone backboard] [sound panel] and [ac panel] to underfloor duct junction boxes indicated. Install feedin conduits in the ceiling space below.

3.5INSTALLATION OF DUCT MARKERS

.1Provide duct markers [on the last insert of all duct runs and on the first insert on each side of junction boxes] [on each duct, in each room and on each side of junction boxes] [on each side of all junction boxes, at the end of duct runs and 4500mm on centre].

.2In resilient floor areas, install temporary duct marker screws. Arrange for flooring installer to form duct markers by punching 6mm diameter holes in the resilient flooring and install a 6mm diameter marker of resilient flooring of contrasting colour at the insert marker location. Use colour markers, blue for telephone, black for low tension, and grey for ac ducts.

.3In carpeted areas, install marker screws level with carpet backing. In nonresilient floors, such as quarry or ceramic tile, install metal duct markers with varying slots in mortar joints.

.4On the inside of the coverplate of the junction boxes, install schedule indicating the distance of the first insert in each direction from the centre of the box. Seal schedule in plastic and mount in a metal cardholder on the back of the coverplate.

3.6INSTALLATION OF OUTLETS

.1Allow for the supply and installation of [] ac outlets, for the wiring of up to [] branch circuits to these outlets. [Mount outlets on preset inserts.][Install outlets by core drilling and afterset type inserts.]

.2Allow for installation of [] telephone and low tension outlets. [Mount outlets on preset inserts.][Install outlets by core drilling and afterset type inserts.]

END OF SECTION

2010-11-01 BMS Version