Using polyvinyl chloride (PVC) windows has been the subject of intense discussions in recent decades. Opinions about the impact on environment and health were divided between chemical industry on one hand and environmental organizations, on the other hand. While the plastics industry says “PVC is similar to any other material”, the results of this study commissioned by World Wildlife Fund and some of the most important environmental organizations, say that the PVC is neither durable nor harmless to health. PVC is currently the most widely used material in Europe. In the UK are sold each year about 6 million PVC windows – two times more than wooden windows. Concern over deforestation and wildlife extinction led to negative reactions on the use of wood as raw material. These worries were heavily loaded in the 90’s by companies in the plastics industry through advertising campaigns like “Save a tree. Get your PVC”, campaigns which promoted plastic as a superior alternative to wood.

PVC pollute the environment in several ways

A product that comes from non-renewable resources can not be durable. PVC has as raw material 40% oil. PVC windows produce 43% more wastes than the wood ones: about 82 % of the waste go to landfills, 15% in incinerators and only 3% are recycled. By 2020, will be produced about 6.4 million tons of waste from PVC windows. Recycling capacity will range, unfortunately, somewhere in a fifth of that amount. An overview of the life cycle and destruction shows that wooden windows are a much lower environmental burden than the PVC.

Eventually, even the burning of PVC produces pollutants. World Wildlife Fund always had the opinion that wood from forests carefully groomed by foresters, represent a good resource, considered inexhaustible. Producers who want to take into consideration the durability, namely the use of natural resources in a careful manner, should take the wood from reliable sources. Currently, Forest Stewardship Council (FSC ) is the only certified system recognized by WWF and by the most important environmental organizations and which guarantee the forestry exploitation (ie science, which gives the durability and the inexhaustible character of the forest resources).

Besides the environmental arguments against PVC, many studies demonstrated that, in terms of life time, wooden windows are 14-25 % more advantageous financially than PVC . There is countless information about the performances of the PVC windows compared to those of wood. Each time, independent organizations like BRE Building Research Institute, demonstrated in comparative studies between wood and PVC that wood has superior technical qualities. On the other hand, several studies commissioned by the PVC industry have demonstrated its superiority over wood. In June 2004, the European Commission presented a long awaited report, which should rectify the situation. * The 325 page study is based on 30 published comparative analyzes and concludes: ” In terms of window frames, one of the most important areas of application of PVC, the used studies does not confer a” victory ” in the sense of preferences, but most have shown that none of these materials have better performance in terms of the standard impact categories”.

Therefore, various interest groups left an open space or interpretation. Despite numerous studies, it could not have been taken a position regarding the ecological safety of PVC till now. * This study addresses to manufacturers and builders, who are forced to decide in choosing the optimum material both in terms of economic and ecological acceptability and also in terms of quality-price ratio.

Numbers and factors determining the purchasing decisions
Basic factors:

Wood PVC
Raw Raw
Approximately 79 % of the wooden windows sold in the UK is made of light wood, such as treated pine. Another type of preferred light wood is the duglas. To these the hardwood windows are added, such as oak and chestnut. Because of their durability in time, these are the top choices and represents about 21 % of sales in the UK. Wood is an unlimited resource and can be considered as sustainable by the responsible foresters. PVC contains 57 % chlorine (which is extracted by passing electric current through salt water). The other 43% are composed of ethylene (water and carbon extracted from oil or gas). The reaction between chlorine and ethylene results in a monomer and vinyl chloride (VCM), and by polymerization, results the PVC. Thus, the PVC is made of 43 % limited resources
Additives Additives
Wood care products: resin and wax that gives the frame a higher impermeability and facilitates application of paint
Fungicides – inorganic boron salts, such as potassium octaborate or azole group representatives, such as propiconazole and tebuconazole.
Solvents – solvents such as turpentine or, more often, water, containing other emulsifying substances that release less volatile organic compounds (VOC) .
Adhesives – to assemble the frame itself, are used both in the factory and at the destination.
In the PVC frames production, other chemicals are also used:
Heat stabilizers – prevent degradation and make PVC waterproof and light –resistant: lead, barium, calcium, zinc.
Lubricants – wax or fatty acids
Fillers – Calcium carbonate
Catalysts sealing – acrylic rubber/chlorinated polyethylene
Pigments – titanium dioxide as a whitening agent.
(Additional information about PVC windows components are listed in Table 1).
Manufacturing Manufacturing
In Windows Wood report design, selection and installation, (Methods of design, selection and installation of wooden windows) the British Society for Research and Wood production (TRADA) say that the manufacture of PVC windows uses energy 8 times greater than that consumed to manufacture the wooden windows . Additives and chemicals used in the production of PVC have been successful both in production and finishing, but it was discovered that at the end of the product life cycle, the recycling is hampered. One of the most controversial aspects of the debate between environmentalists and manufacturers of PVC is if during the production process dioxins are released and whether they are harmful to the environment. Cadmium-based stabilizers are no longer used in Europe in the production and processing of PVC windows. Today we can see a return to lead salts, much less harmful to the environment than the system with barium and cadmium, although cadmium is technically superior.

Table 1, Chemical components of PVC windows

Material Role Quantity
PVC polymer 81,5%
Acrylic rubber sealing catalyst 6,0%
TiO2 pigment 3,5%
Lead phosphate and stearate stabilizer 2,5%
Calcium carbonate filler 5,0%
Wax and fatty lubricants 1,5%

Windows market size:
Each year in the UK are sold nearly 12 million windows. Almost half of them are PVC . Wooden windows have a market share of approximately 25%.

Wood PVC
Long time ago, in the Western Europe, the wood was the most commonly material used for windows. In the ’60s, in the UK, about 60 % of the windows were made of wood. In 1983, only half of the existing windows were made out of wood, and beginning with 1994, the market is dominated by the PVC windows, the wooden windows share sold decreased by 23%. Since the ’90s, the number of sold wooden windows began to grow from year to year (see Figure 1). In 2000, the UK has sold about 3 million wooden windows, of which 57 % in the public sector and 43% in the private sector. 86% of sold wooden windows were purchased in order to achieve 14% for the renovation and construction of new buildings. In 2003, the UK has sold 3.6 millions of wooden windows, evaluated to 360 million pounds (about 522 million). The demanded researches in 2004 by the British Woodworking Federation and Michael Rigby Associates marketing firm, show that 79% of sold windows are made from light wood and 21% of hard wood. These studies estimate that 85 % of hard wood and 83% of soft wood come from “sustainable” cultures. In 2003, Great Britain consumed 37 million cubic meters of which 85 % were attributed to the construction industry. In Europe, PVC is still the most common material used to make windows. 13% of PVC consumption in Europe is attributed to manufacturing windows. After Germany, the UK is the second largest market in Europe. Over the years, sales of PVC in the UK were up almost continuous (cf. Figure 2 ) and went up in 2001 to 5.7 millions PVC windows . That same year, the public sector customers – 33% and private sector 67%. PVC was used for renovations in proportion of 83 % and for new constructions in proportion of 17 %. PVC market sales in 2003 were estimated at 4 billion pounds (5.8 billion euros) and sales of PVC windows have been estimated at about 2 billion pounds (2.9 billion euros). PVC has been the dominant material in the production of windows. UK produces annually about 790.000 tons of PVC (which worth 392 million pounds, or 569 million euros). According to the statements of the representatives of the packaging industry, construction is the second buyer of plastics. 250.000 tons of polymers are used annually. Plastics are used mainly for the production of windows, doors, pipes, cables and floors. In 1989, in the UK, approximately 100,000 tons of raw materials were used for the manufacture of PVC windows. In 2000, the necessary raw material from the PVC was 240.000 tons.
Resource inventory Resource inventory
Wood from certified sources is a real inexhaustible resource. Approximately 94% of windows sold in the UK are made of wood from Scandinavia (especially Sweden). UK is the 4th largest importers of wood products in China, Japan and the United States of America. .In 2003, Great Britain exported 33 million cubic meters of wood products and gained about 5 billion pounds (7.26 billion euros). Meanwhile, from the british forests were cut approximately 7 million cubic meters of wood for commercial purposes, with the FSC agreement. The wood production in the UK, estimated by FSC for year 2020 is approximately 15 million cubic meters. Worldwide, forest areas which covered 6 billion hectares at the end of the last glaciation, decreased to 3.9 billion hectares (about 30 % of the dry surface of the planet). Existing forested area is composed of 95 % of natural forests and 5% of forest plantations which produce about 1.6 billion cubic meters of wood. Globally, in 2002 there were 390 million cubic meters of processed wood (hard wood and soft wood). Meanwhile, the global consumption increased to 388.9 million cubic meters of processed wood. Worldwide, many times, wood is procured illegally from forests – about 10 % of the annual production of wood in the UK is of illegal origin. 850 million hectares of forest are destroyed around the world and each year another 14.6 million hectares are added. The illegally produced wood in Russia reaches the countries with high processing power like Sweden, Finland and the UK. For this reason, it is important that the wood used to manufacture window to come from a licensed place and certified by FSC. The PVC contains 43% oil, a limited raw material. From studies it can be concluded that the british oil deposits will be sufficient until 2023. In February 2003, a study called the White Paper concluded that beginning with 2010, the UK will become an oil importer. The British government concluded that “up to a high degree of self-sufficiency to oil imports will make a country vulnerable to the price increment and to the supply interruption of the raw material due to political instability or conflict.” Although it is difficult to estimate the amount of oil required to manufacture PVC windows, it is clear that by decreasing the resources, will lead to higher prices. In 2002, Great Britain used 69 million tons of oil, of which 40 million were imported. The British government expressed the desire to limit dependence on fossil fuels and oil. In Kyoto Protocol, the UK signed up to reduce the greenhouse gas emissions by 12.5 % below the level recorded in 1990. The government signed up to reduce emissions by 60% by 2050 and carbon dioxide emissions by 20% by 2010. Emission of carbon dioxide derives, for example from the combustion of fossil fuels to produce electricity. Inter- State Association for climate (IPCC ) stated in the third annual report that there was a significant increase in greenhouse gas emissions and that it can be observed the appearance of a global warming phenomenon emergence. The United States is the most important pollutant, being responsible for 24% of annual emissions of carbon dioxide. In Great Britain, in 2003, there was an increase in carbon emissions dioxide instead of a decrement. Therefore, Great Britain must have some relevant solutions to help reduce dependence on fossil fuels that contributes to negative consequences on climate change.

* Source http://komfortwood.utopium.eu/INFORMATION.html. * Article taken from the Wide Forest site (www.wwf.org.uk) – „Window of Opportunity” * More information can be found on nongovernmental and environmental sites as well as on www.wwf.org.uk, www.foei.org (Friends Of The Earth), www.woodlandtrust.org.uk (Woodland Trust), www.fsc.org (Forest Stewardship Council), www.greenpeace.org (Greenpeace).