Energy Savings

In renovation & new build

Reducing energy consumption is one way to save energy. Heating the home guzzles the most energy in English homes, and about 40% of total energy consumption is spent on keeping the house heated.

With the prospect of rising energy costs in the coming years, heat is a major expense for homeowners. Reducing unnecessary energy waste leads to huge savings.

Think long term when it comes to renovation

Replacing 15 to 20-year-old windows makes it possible to reduce the house’s heat loss by about 30%. This reduces the heating bills and gives a family a bit more spending power.

Energy-enhancing solutions are not free, but bear in mind that the cost of new windows is a one-off expense, which should be regarded as an investment that will soon pay for itself.

Example: 20 to 25-year-old windows have a UW-value of about 2,5. New KASTRUP ENERGY triple glazed windows have a UW-value of 0,78. Let’s assume a home has a 50-m2 window surface and heating costs of around 14 pence per kWh. Consequently, with Kastrup windows you will save more than £800 on heating per year.

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Sustainable new build

Right now, the trend is energy-efficient housing, and the demands for this are greatly increasing.

That does not only mean building in an energy-efficient way. It also means that you need to create value in the home that will last for several years. This is why Kastrup develops its products with an eye for durability, longevity and the technological challenges of tomorrow.

New build gives you the freedom to design everything exactly as you want. We are seeing larger areas of glass in new, modern houses. Kastrup’s most slender window series INVI, which is perfect for this type of new build, our AluFrontLine panelled door with wood on the interiors and aluminium on the exterior, and our sliding doors enable you to create a modern, high-quality home.

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Valuable facts for your new windows

UW value in W/m2K = the window’s heat insulation
The lower it is, the less heat loss. The overall UW value of the window is a measure of how well the window insulates. The Uvalue varies depending on the size and design of the window.

Ug value in W/m2K = the heat insulation of the glass
The lower it is, the less heat loss. The Ug value of the glass is an expression of the insulating ability of the glass measured at the centre of the glass.

G value in % = solar energy transmission
The higher it is, the warmer it is. The G value is that part of the sun’s heat that penetrates the window. If the amount of solar heat outside is 100% and the G value of the window is 0.63, this means that 63% of the sun’s heat penetrates the window.

LT value in % = light transmittance
The higher this is, the lighter it is. The LT value describes the proportion of sunlight that penetrates the glass. If the LT value of the glass is 0.8, it means that 80% of daylight penetrates the glass.

RW value in dB = noise reduction
The higher it is, the greater the silencing effect. RW is an expression of the noise-cancelling effect of the glass. The human ear experiences half the noise with a silencing effect of 8-10 dB.

Double glazing or triple glazing

When you are choosing window glass, consider whether the pane should be constructed as double glazing or triple glazing and what quality it should be.

The cheapest solution is double glazing. One advantage of the two glass panes is that you get more daylight and thus more heat from the sun in your living room. On the other hand, the heat insulation is poorer than with triple glazed windows, and this impacts the heating bill and comfort during the winter.

Triple glazed windows provide better energy savings and no draught from the window surface. There is less natural heat from the sun that penetrates the glass and triple glazing is also about 10% more expensive compared to the cost of a double-glazed window. When fitting new windows in your home, you should regard it as an investment in terms of comfort and reduced heating costs.

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