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Trickle vent double glazing

If you have ever come across the term Trickle Vent Double Glazing you might be thinking that this is some form of modern innovation which has been introduced to further increase the thermal efficiency of Double Glazing. You would of course be mistaken.

In fact the Trickle Vent referred to is a very small opening on the window to allow small amounts of ventilation into rooms that are intended to be ventilated naturally rather than by some mechanical means.

Double glazing is a very effective means of controlling the heat losses from within a building. The effectiveness of a double glazed installation will stop any draughts that may have been present previously. Whilst draughts are the unwanted ingress of air from the outside, in stopping the draughts the double glazing also limits the change of air within the room that draughts would otherwise have contributed to. Draughts are uncontrollable what is required is a controlled form of ventilation.

The quality of the air in a building is an important consideration for a number of reasons. The optimum water balance is vital in order to avoid musty smells, moisture, moulding and allergies. Modern building and the highly effective double glazing systems minimise heat loss through the double glazed windows and doors. However, a certain level of cold air ingress into a room is still required for several reasons. The fabric of the building is at risk without some level of fresh air movement through the double glazed window system. The occupants’ health is also affected by the consequences of a lack of ventilation.

Taking these factors into account modern double glazed window systems can have a trickle vent built into the double glazed frame. This will enable a light trickle of cold, fresh air to enter the room via the double glazing. Most will have a facility for you to control the level of air flow through the trickle vent. Controlled natural ventilation is a healthy option to air conditioning. It is also a more sustainable choice as it requires to uses no energy and has no running or maintenance costs.

The fitting of these vents will avoid any damage to the fabric of the building by reducing any levels of condensation. In a property containing 4 people, each will contribute approximately 4 pints of moisture per day through showers, baths, boiling kettles, cooking etc. This adds up to well over 100 pints of water vapour per week - a huge volume of moisture, which must go somewhere. Add the other airborne contaminants which exist in a typical home - dust, tobacco products, exhaust gases and it not difficult to understand the scale of the problem.

To solve the problem Trickle Vents can be fitted to new or existing windows. These can be fitted in the top of the frame or if there is no room in the frame a glazed-in vent can be fitted on top of a glass unit. The added cost of fitting these vents is minimal when set against the total cost of the double glazing.

You may ask why go to the trouble of fitting these Trickle Vents when all that is necessary is to open the window. Trickle venting as the name suggests allows a very small amount of air into the building without disturbing the effectiveness of the Double Glazing. They can remain open for as long as thought necessary and closed to suit. Opening a window will not only allow too much cold air into the building but may be a security risk particularly if you were to leave the building having inadvertently left it open.

In summary buildings need to be well insulated in order to reduce energy consumption and improve the comfort of the internal environment but adequate ventilation is also necessary. In modern buildings constructed to meet present day building standards some form of ventilation is also necessary. Trickle ventilation will satisfy that need.