Contract Window Coverings

This collection of window covering products includes fabrics suitable for Vertical, Roller and Pleated blinds, and slat for Venetian blinds. Each product has been selected for its aesthetic quality, and its suitability for use in public and commercial buildings (i).

Fire Regulations

Fabrics within this collection meet with the fire regulations specified by European Standards. The fabrics have either been woven with non-flammable, fibre glass, Trevira CS or impregnated/coated with fire retardants.

Details of the standards are given below;

BS 5867 Part 2 Type B (1980) (British)

In accordance with BS5438: 1876 Test Method 2. Textile Fabrics & Fabric Assemblies subjected to a small Igniting Flame.

M1 Standard (French)

In accordance with NF P 92 - 503. The test is particularly hard on synthetic fabrics like fibreglass and polyester. It focuses on the melting droplets as the fabric is subjected to a flame.

B1 Standard (German)

In accordance with Din 4102-B1. The test is particularly hard on natural fabrics.

Technical Performance

Architects and design engineer use the solar and optical properties of fabrics to assist in the design of temperature control systems within the buildings. The installation of internal window blinds can be more cost effective than installing air conditioning system, to control the building heat. The installation of suitable window blinds can reduce the glare within a building, which is particularly relevant where computers are used intensively. There are legal obligations stated in the health and safety regulations for areas with display screen equipment (ii) (iii) require that 'windows shall be fitted with a suitable system of adjustable covering to attenuate the daylight that falls on the workstation.'

Technical Properties

The technical properties are given for each fabric including; Solar Transmission, Reflectance and Absorption. They have been calculated (iv) in accordance with ISO 9050, ISO/160 and BS EN 410 (v). The Total Solar Energy Transmittance and Shading Co-efficient values have been derived in accordance with European Standard Pr EN 13363-1 (vi) for the fabrics in 4 standard glazing configurations Pr EN 13363-1.

Solar Transmission

The ratio of the amount of total solar energy allowed to pass through a glazing system to the amount of total solar energy falling onto the glazing system.

Expressed as a percentage or decimal portion of a total unit of:

1. For example, if half the total solar energy transmits through a glazing system its total solar transmittance would be expressed as 50% or 0.50.

Solar Reflectance

The ratio of the amount of total solar energy which is reflected outward by a glazing system to the amount of total solar energy falling on the glazing system. Expressed as a percentage or decimal portion of a total unit of 1.00. Solar Absorption = 1.00 (solar transmittance + solar reflectance)

Shading Co-efficient

This is the ratio of the heat gain (or solar energy entering a room) with the blind in place, to that of the heat gain of ordinary clear glass. Results are given for single glazing, double glazing, triple glazing and double glazed glass with low emmitance coating. The lower the shading co-efficient, the greater the effectiveness of the fabric. In the calculation of the shading co-efficient the following g and u values were assumed;

The assumed u values for single, double and double low-e glazing were 5.7, 3.0 and 1.6Wm^-2°C^-1 respectively.

Light fastness

The light fastness indicates the stability of the fabric's colour after subjection to natural light.

Measured against a scale of 1-8.

Where 1 is poor and 8 is good.

British Standard = 4

FOOTNOTES:

(i) In response to the EU DIRECTIVE 90/270 passed in 1990, which deals with daylight regulation at the office environment. Foundation legislation in European countries.

(ii) Department of Employment The health and safety (display screen equipment) regulations 1992. Statutory Instrument 1992 No 2792. London, HMSO, 1992.

(iii) Health and Safety Executive Display screen equipment work. Health and safety (display screen equipment) regulations 1992. Guidance on regulations. London, HMSO, 1992.

(iv) Spectral measurements made by Professor .M. G. Hutchins, Solar Energy Material Research Laboratory, Oxford Brookes University.

(v) International Standard ISO 9050, ISO/TC 160, 'Glass in building: and Ultra-violet Transmittance, and related Glazing factors 'Geneve, Switzerland, 1990; BS EN 410 Glass in building - Determination of luminous and solar characteristics of glazing, 1998.

(vi) Pr EN 13363-1, Solar protective devices combined with glazing - Calculation of solar and light transmittance - Part 1:Simplified method, CEN Draft Standard, CEN./TC89/WG7 N85, (1998)

Fabric Properties