Reflectivecoated glass

Reflective-coated glasses offer medium to high solar gain control by the action of a range of reflective coatings. Coatings may be applied on-line during the float process or subsequently as sputtered surface treatments to clear or body-tinted glass.

Deskcant

Fig. 7.17 Typical double-glazing unit

Deskcant

Fig. 7.17 Typical double-glazing unit

Table 7.3 Typical overall U-values (W/m2 K) for windows, doors and roof windows

Type of frame

Type of frame

Table 7.3 Typical overall U-values (W/m2 K) for windows, doors and roof windows

Wood

Metal

Thermal break

PVC-U

Glass separation (mm)

6

12

6

12

6

12

6

12

Windows

Double glazed

3.3

3.0

4.2

3.8

3.6

3.3

3.3

3.0

Double glazed, low E glass

2.9

2.4

3.7

3.2

3.1

2.6

2.9

2.4

Double glazed, argon fill

3.1

2.9

4.0

3.7

3.4

3.2

3.1

2.9

Double glazed, low E, argon fill

2.6

2.2

3.4

2.9

2.8

2.4

2.6

2.2

Triple glazed

2.6

2.4

3.4

3.2

2.9

2.6

2.6

2.4

Double glazed doors

Half glazed

3.1

3.0

3.6

3.4

3.3

3.2

3.1

3.0

Fully glazed

3.3

3.0

4.2

3.8

3.6

3.3

3.3

3.0

Roof windows less than 70o from horizontal

Double glazed

3.6

3.4

4.6

4.4

4.0

3.8

3.6

3.4

Other windows/doors

Single glazed windows/doors

Solid timber panel door

Half glazed/half timber panel door

Wood

4.7 3.0 3.7

Metal 5.8

Thermal break 4.3

PVC-U 4.7

Available colours in reflection are blue, green, grey, silver, gold and bronze, although colours by transmission may be different (e.g. Reflectafloat is silver in reflection but bronze in transmission). By combining the range of coatings with different body-tinted glasses a wide range of solar control properties is achieved.

Where reflective coatings are to be applied after the float manufacturing process, all other working such as toughening and bending must be completed prior to the surface treatment. While many mineral coatings are durable in normal use as single glazing, they are damaged by abrasives, and may also exhibit minor imperfections, although these are considered acceptable if not observed at a distance closer than 3 m and are less than 2 mm in diameter.

0 0

Post a comment