Technical Manual · 03 / 20

Mineral Fiber Ceiling Tile

Installation · Accessory Fitting · Storage & Handling Guide

Application Interior exposed-grid / concealed ceilings

Matching system Painted T-bar grid system

The workhorse acoustic tile · weak against moisture, soiling and impact

Made from granulated mineral wool by forming, drying and cutting, the mineral fiber tile is the workhorse of acoustic ceilings in offices and public buildings. It is light, absorbs sound well and goes up quickly, but it has low strength and is vulnerable to moisture and soiling. Every installation and storage rule below follows from those three weaknesses.

01 Product Overview

1.1 Construction

• Mineral wool: granulated wool (blast-furnace slag spun into fiber), 60 %–80 % of the mix, providing sound absorption and fire performance;

• Binder: starch, modified starch or water glass, bonding the fibers into a board;

• Fillers: perlite, clay and similar, adjusting density and strength;

• Face: natural, spray-coated, film-faced (soil-resistant), needle-punched pattern or embossed.

1.2 Standard Sizes

Table 1-1 Standard supply sizes

1.3 Where It Suits and Does Not Suit

Suitable

• Offices, meeting rooms

• Schools, libraries

• Hospital waiting areas

• Public areas of shopping malls

• Halls needing reverberation control

Not suitable / special type required

• Kitchens, bathrooms, pools (free water and high humidity)

• Outdoors or semi-outdoors

• Workshops with corrosive gases

• Spaces needing frequent scrubbing or disinfection

• Areas with a high risk of leaks above the ceiling

About moisture resistance - The strength of a mineral fiber tile comes from the binder bridges between fibers. Once water is absorbed, those bridges soften and the tile sags slowly under its own weight. The process is irreversible: it will not flatten again when dry. Moisture protection is therefore the first principle for this tile, not a secondary precaution.

02 Preparation Before Installation

2.1 Site Conditions

• Services above the ceiling installed, pressure-tested, insulated and fire-stopped, with sign-off;

• No leaks in the roof or in the floor above, and pipe pressure tests passed (a mineral fiber tile that gets wet is effectively scrap);

• Wet trades on walls and floors complete and dry, openings closed;

• Ambient relative humidity ≤70 %; above that, switch to the moisture-resistant type and increase ventilation;

• Bring tiles on site 24 h in advance, stored flat in the original packaging, and do not open packs early (an open pack absorbs moisture).

2.2 Tools

Table 2-1 Main tools

2.3 Accessories

As in 05 Painted T-Bar Grid: main runner T24×38 @≤1200, cross tee T24×26 @600, L wall angle, φ6 hanger rod, hanger clip, splice clip and M8 expansion bolt. Mineral fiber tiles are light, so hangers at 1200×1200 are sufficient and no closer spacing is needed.

03 Method 1: Exposed Grid (Mainstream)

1. Set out and fix the wall angle

   Close the level line on all four walls, keep the lower edge of the L angle flush, fixings at ≤300.

2. Install hanger rods and main runners

   Hangers at 1200×1200, main runner camber 1/200–1/300, joints staggered.

3. Install cross tees

   At 600 spacing, tabs pushed fully home, installed to a taut line.

4. Level

   Flatness ≤3 mm/2 m, joint height difference ≤1 mm.

5. Trial lay one run

   Lay one full run dry and check pattern direction, joints and shade before continuing.

6. Lay the tiles

   Support the tile on both edges with both hands, tilt it into the grid and lay it flat; never grip one corner, as the corners are the weakest point of a mineral fiber tile; keep pattern and needle direction consistent.

7. Cut tiles

   Measure at two points and take the smaller value; score several times with a sharp knife and snap over a block; cut edge to the wall.

8. Cut openings and clean

   Use a hole saw and fit a protective ring around the opening; dust off with a soft brush or a vacuum, never a wet cloth.

Three hard rules

① Never stand on the tiles and never rest tools on them (local pressure dents the tile permanently);

② wear clean gloves throughout, since sweat and grease leave permanent marks on light-colored faces;

③ cut edges must face the wall or a concealed side, because an exposed cut absorbs moisture and crumbles.

04 Method 2: Concealed Grid

Use tongue-and-groove mineral fiber tiles (grooved on all four edges) with the concealed-grid runner series; the finished surface shows no grid. The sequence matches Chapter 5 of 01; the differences are:

• The tongue-and-groove edge is weaker than on gypsum tile, so a trial lay is mandatory: confirm that the joints run straight before final fixing;

• Use a suction lifter to install; never hook a finger into the groove (the groove chips immediately);

• Leave a 2 mm joint with no filler; a concealed-grid field is hard to repair once part of it is damaged, so always provide access panels.

05 Accessories and Details

• Wall angle: L25×25, fixed at ≤300, miterd at 45° at corners;

• Cross tee: the end tab must be pushed fully home — failing to do so is the main cause of tiles dropping;

• Hanger rod: φ6 threaded rod; never substitute wire or cable ties;

• Edge trim: turn the cut edge to the wall and, where needed, cover it with a matching trim strip.

06 Detailing

• Luminaires: up to 3 kg may be fixed to the tile face with the integral clips, with a washer on the back; over 3 kg needs independent hanger rods and must never hang from the grid or the tile;

• Air grilles: fit a 25×25 aluminum angle frame around the opening, bearing on the main runners;

• Access panels: 600×600, made up from a full tile, frame on at least 2 independent hangers, cover fitted with a safety chain;

• Spaces with high acoustic demand: leave a 200–300 cavity behind the tiles to improve low-frequency absorption markedly;

• Wall junction: leave a 5–8 mm gap and close it with a matching trim strip or sealant (fungus-resistant sealant in wet areas).

07 Quality Acceptance

Table 7-1 Permissible deviations

08 Common Problems

Table 8-1 Typical defects

09 Product Storage and Handling

9.1 Environmental Requirements

Table 9-1 Warehouse conditions

9.2 Stacking

• Pallet or dunnage at least 100 off the floor and 100 from walls;

• Face up and flat, stack height ≤1.2 m, at most 10 layers of 15 mm tile;

• Cover with a vapor barrier overhanging at least 200 on all sides, without wrapping the whole stack;

• Never stack other materials on the tiles: compressive strength is low and a load leaves permanent marks;

• Take tiles layer by layer from the top, never from the middle.

9.3 Shelf Life

Recommended stock ≤6 months, maximum ≤12 months. Sample tiles that are out of date or come from damaged packs: check for sagging, powdering at the edges and excessive moisture content. Dispatch first-in-first-out.

10 Transport and Safety

• Load flat, stack height ≤1.2 m, secured with strapping and covered with a rain-proof tarpaulin for the whole trip;

• Never ship with heavy goods that can crush the stack; pass tiles one by one when handling;

• Cutting produces dust: wear a dust mask and goggles;

• Mineral fiber can irritate the skin: wear long sleeves and gloves, and wash after work;

• Use a safety harness above 2 m, work from trestles or scaffolding, never stand on the tiles.

11 Appendix: Checklists

11.1 Delivery Inspection

• Size, thickness and batch consistent; one batch per space

• No sagging, stains or chipped corners

• Packaging intact, no signs of damp

• Pattern direction clearly marked

• NRC and fire performance test reports supplied with the shipment

11.2 Before Installation

• Pressure testing, insulation and fire-stopping above the ceiling complete

• Ambient humidity ≤70 %, no leaks

• Grid components from the same series, tabs intact

• Grid layout and luminaire positions set out

• Clean gloves and a vacuum on hand

Mineral Fiber Ceiling Tile · Installation and Storage Guide · V1.011 chapters · 3 figures · Dimensions in mm