Black wool serge has been used for stage and theatre curtains for very many years for a few reasons. It is made from sheep’s wool which has been woven to produce a fabric which is very thick and rich and is also very durable. It is inherently flame retardant to BS5867 which makes it an ideal fabric for stage curtains since it can be used "as is" without any retardant needing to be added to it.

Black wool serge curtains can be used to muffle sound and improve the acoustics. Wool serge is already a thick material but can be of varying weights. The average is 500 gsm (grams per square metre) but can range from 300 gsm up to 1,000 gsm – a kilogram, or 2.2lbs. Then, of course, it can be pleated to a greater or lesser degree: the more pleats there are, the better the curtain will be at preventing sound waves travelling through it. This means that it can have a number of uses such as backdrops, legs, tormentors, and flybars. In some theatres it has even been used for front of house curtains. Wool serge is available in widths of 120 cm to 180 cm – approximately 4 feet to 6 feet.

Of course, black serge curtains can really help to reduce light penetration. They are not completely blackout but can have a very strong dimming effect. Again, the thicker the material and the more pleats there are, the more light will be prevented from travelling through. Furthermore, when used as a backdrop it reflects very little light as well, so if bright stage lights are directed at it most of the light will be absorbed. If it is necessary to prevent all light passing though black serge, then of course it can be lined as well, and a side benefit of that is that it will help even further with the acoustics.

Of course, black wool serge is not the only material that can be used for stage curtains. There are many others. Cotton velvets have a directional pile with a great matte finish. They come in a range of colours, so are suitable for fronts of house curtains as well as for other purposes, and there is also a budget range of cotton velvets available. In order for them to become flame retardant, they need to be chemically treated, and the effect of this will wear off with time and depending how often they are washed or dry cleaned. This means that they will need to be retreated from time to time.

Probably the most luxurious and heavy stage velvets are mohair velvets which can be used for front of house curtains. Some of these can be embossed with a pattern, or perhaps with your theatre logo on them. They have a great colour clarity and very good acoustic qualities.

Then there are polyester/synthetic stage curtains as well. These are very resistant to wrinkling, so are more suited for touring than other velvets. However, they have another big benefit in that they are inherently flame retardant as well. One brand of polyester materials is Trevira CS. The chemical structure of this polyester fibre means that it cannot burn, and in the event of a fire it will only give off a very small amount of toxic fumes.

Because polyester fibres need no chemical treatment in order to make them fire resistant, it is also beneficial to the environment. The chemicals that are added to materials that are normally combustible such as cotton velvets are harmful to the environment, so by specifying polyester materials for your stage curtains you are not in any way damaging the environment. Furthermore, you won’t need to have them retreated on a regular basis as you do with other materials, saving both cost, and environmental damage.

Of course, when you are considering new theatre curtains, the price will be high on your list of priorities. The type of material you choose, and the actual size of the curtains, will be major factors in the cost, and since no two venues are the same it is not possible to quote hard and fast figures. However, a good curtain manufacturer will be happy to meet you on site and discuss all your options.