Next. Advanced technology that doesn t cost the Earth

Transcription

1 Next Generation Windows Advanced technology that doesn t cost the Earth

2 Our present to the future There is now widespread acknowledgement that the world s natural fossil-fuel resources are finite and, unless some drastic action is taken, we will face an energy supply crisis sooner rather than later. It makes eminent sense therefore, to reduce our energy consumption in order to cut back on energy production. In both situations, the NorDan NTech Passive window, with its astonishingly low whole window U-value of 0.7 W/m 2 K, was used in an external envelope which was highly thermally efficient, yet allowed the inside of the houses to be light and airy. The Offsite 2007 exhibition at the BRE in Watford offered a glimpse of the way ahead for cost-effective, thermally-efficient and energy-conserving construction in the form of several revolutionary buildings. NorDan was proud to be associated with two of the houses on view which achieved the highest energy ratings: the Kingspan Lighthouse which achieved Level 6 and the Stewart Milne Group Sigma Home, which was awarded a Level 5 rating. Image courtesy of Stewart Milne Group Kingspan Lighthouse This building combines clever use of an open-plan arrangement within a highly insulated and air tight construction, in conjunction with various advanced energy-saving technologies, to achieve the highest energy rating available Code Level 6. NorDan NTech Passive windows were incorporated into the construction, allowing the area of glazing to be optimised without compromising the thermal efficiency of the building. Stewart Milne Group Sigma Home This four-storey demonstration house achieved an energy rating of Code Level 5 under the Code for Sustainable Homes. Here the large windows were designed to optimise natural solar gain and provide passive security surveillance at upper floor levels. This was made possible by reducing the whole window U-value to 0.7 W/ m 2 K (well below the Irish standard of 2.2 W/m 2 K) using the NorDan NTech Passive window system.

3 What is NTech Passive? This product combines the latest cutting-edge technology with good, old fashioned Norwegian craftsmanship and was developed from an award-winning prototype, which had been produced in response to a challenge to lower the U-value standards of the late 1980s. The standard NorDan tilt & turn window has been used in basically the same form for more than forty years in buildings situated in some of the most inhospitable parts of Europe. In its current form this original window, with it s North European pine frame and sash combined with a double-glazed (low-e coated) unit incorporating an aluminium spacer, achieves an overall U-value of 1.6 W/m 2 K (1.4 W/m 2 K with argon gas in the cavity). Why did we do it? The current Irish standard is 2.2 W/m 2 K and the Norwegian domestic standard is to be reduced to 1.2 W/m 2 K by August The challenge for NorDan was to enhance the thermal performance of its products and try to achieve a value under 1.0 W/m 2 K. This they have achieved, quite dramatically with the development of the NTech Passive window with a remarkable U-value of just 0.7 W/m 2 K.

4 NTech low energy window NTech passive window 20% reduction IN energy loss! 92mm insulated frame (on 3 of the sides) Double glazed sealed units Opening and fixed windows Low-emissivity coated glass SuperSpacer 4mm glass-16mm Argon- ES4mm glass U-value = 1.2 W/m 2 K 54% reduction IN energy loss! 105mm insulated frame & sash (on all 4 sides) Triple glazed sealed units Low-emissivity coated glass SuperSpacer ES4mm glass-16mm Argon- 4mm glass-16mm Argon- ES4mm glass U-value = 0.7 W/m 2 K

5 How did we do it? Firstly, detailed tests were carried out to identify where the main areas of heat loss occurred. From the results it was clear that the frame, although constructed from selected quality pine which is regarded as having excellent natural insulating qualities, needed to have an additional thermal break included if the frame was not to become disproportionately thick. After much intensive research and testing, a robust, highly efficient and environmentally friendly insulation board was developed which could be laminated into the pine sections, prior to them being machined into sections for product assembly. The resulting components were then run through a rigorous testing schedule to ensure that the new sections could perform to NorDan s high standards of weather resistance and security. SuperSpacer technology Secondly, NorDan tried several glazing combinations with various edge spacing bar systems before establishing that the best results were obtained with the use of a triple glazed unit with argon gas in the cavities, a combination of super low emissivity coatings and an Edgetech silicon SuperSpacer. Unlike the typical aluminium spacers, SuperSpacer technology has a much lower thermal conductivity. Consequently the temperature at the edges of the glass is several degrees warmer. By keeping the edge of the glass warmer, the window can withstand even lower external temperatures before condensation forms on the inside. Energy saving Subsequent computer modelling and independent verification proved that the NTech Passive product had a whole-window U-value of 0.7 W/m 2 K (the actual figure achieved was 0.66 W/m 2 K), far superior to what was required but which set a new standard for those who are serious about energy conservation. By employing this advanced technology, just think how much energy could be saved by using NorDan NTech Passive windows. For example: A reduction in U-value of 0.1 W/m²K per 1m² of window achieves an annual energy saving of 10 kwh. Each 0.1 of a U-value equates to 10 kw/m² of glazing per annum, based on an average temperature differential of 6 C (there are regional variations on this, which means that, for instance, this figure can vary on average from 8.1 kw/m²k in Aberdeen to 5.5 kw/m 2 K in London). Electricity costs are on average 16.3 cents/kw/h. An average sized 3 bedroom house has 20m² of external glazing. Therefore, in our average 3 bedroom house, for every 1.0 of a U-value, the annual cost for electrical heating lost through the windows will be (20 x 10 x 16.3) 326. If this is applied to a current standard glazing specification with a U-value of 2.2 W/m²K, then the average annual cost to the householder would be ( 326 x 2.2) If the same house was fitted with NTech Passive windows (0.7 W/m²K) that would fall to (326 x 0.7) The energy saved in the process over the 60 year expected service life of the window would have a consequent knock-on effect on the power generation requirement, resulting in a reduction of the overall emissions into the atmosphere. A winwin situation for both customer and planet! This picture was taken with an infrared camera. Colours indicate the surface temperature with the white and red areas indicating high heat loss. Heat is clearly escaping from the one window. The opposite window showing extremely low energy loss is a NorDan Standard window. When it comes to energy conservation, it has to be NorDannaturally.

6 Creative potential for architects By improving the insulation value of windows, it is possible to offer larger and more aesthetically versatile glazing solutions to building designers, without compromising on energy efficiency. This impacts on the internal space where greater floor area is made available by having the ability to place furniture closer to windows whilst still maintaining internal comfort levels in the vicinity of the glazed areas. By using the new NTech window technology, designers are offered greater scope in the overall design of buildings, whilst satisfying increasingly stringent environmental requirements. NorDan has always been in the forefront of window design and technology. With this innovative development of a tried and tested window system, window technology has been taken into the next generation, for the benefit of this, and future generations. There are many similarities between the climate of Norway, where NorDan NTech windows are designed, developed and made, and that of Ireland, where the wind-chill factor exacerbates the low temperatures we experience in winter. Using NorDan NTech windows ensures an equable internal climate, no matter how inclement the external weather may be. Measured temperature ( o C) Calm Light Wind speed (m/s) Actual temperature ( o C) Medium Strong The wind-chill factor exacerbates low temperatures With the very real threat of global warming, windows play an increasingly important part in the retention of heat within buildings and in the consequent reduction in wastage of vital energy resources. Despite the adoption of more stringent standards for the performance of windows, there is still scope for improvement. To this end, NorDan and SINTEF (The Foundation for Scientific and Industrial Research in Norway) are cooperating to achieve even lower U-values in our highly efficient and environmentally friendly windows. In the home of the future, windows with a U-value similar to the NTech Passive, as part of an airtight, highly insulated external envelope, will ensure that energy usage and bills will be greatly reduced, to the benefit of the planet.

7 Fresh air with added comfort A well insulated window ensures an improved living environment, as reduced heat loss gives a more stable indoor temperature. This makes it easier to maintain a comfortable internal environment free from cold spots. Research has shown that an internal air temperature of around 20 o C feels fresher and more comfortable than one of around 23 o C, even if there is no measurable difference in the air quality. Generally speaking, it is better to avoid high indoor temperatures. Temperatures in excess of 24 o C, in combination with high humidity, lead to an increase in house mite and other deleterious micro organisms within a building. Higher temperatures are also the cause of condensation and the release of gasses from building materials and furnishings. What Next? At NorDan, everything is done in the pursuit of excellence by combining continuous scientific-based improvement with the best environmentally-responsible practices. Currently, the NTech range is in production and covers the majority of standard products. The NTech Passive and the standard high-performance timber window are both available with a proprietary NorDan aluminium cladding to improve life-span and reduce maintenance costs. In order to maximise the enormous potential of the NTech range, NorDan is developing a highly insulated door to complete the energy-efficient filling of all external openings in the new types of construction. The programme will continue with a reappraisal of all other window types currently produced in order, ultimately, to offer a complete range of energy-efficient options to architects and designers.

8 For further information, please contact your nearest NorDan Ireland office: Commercial residential NorDan Vinduer Ltd Spilmak Place, Bluebell Avenue, Bluebell Industrial Estate, Dublin 12 NorDan Residential, Bluebell Avenue, Bluebell Industrial Estate, Dublin 12 NorDan Residential, Link Road, Ballincollig Industrial Estate, Ballincollig, Cork NorDan Residential, Oldcastle Road, Kells, Co. Meath NorDan Residential, North Point, Tuam Road, Co. Galway Tel: Fax: Tel: Fax: Tel: Fax: Tel: Fax: Tel: Web: Advanced technology that doesn t cost the Earth