Products supplied by BJH Windows & Conservatories


How should you take care of Ultraframe Conservaglass?

Please see the downloadable attached guide - Conservaglass Maintenance

Why do I have condensation on the outside of my windows?

Condensation is the process by which water vapour in the air is changed into liquid water. Condensation generally occurs in the atmosphere when warm air rises, cools and loses its capacity to hold water vapour. The water vapour condenses on a cool surface to form water, this is a normal reaction when warm air meets a cold surface. Condensation occurs naturally in our environment.

Condensation affects new and old buildings alike. As properties have become better heated and insulated the instances of condensation forming are on the increase. Older style houses were often built on suspended floors, had chimneys and were generally quite draughty. First evidence of condensation may be water droplets forming on the inside of the window pane, because the glass has a lower temperature than the fabric of the wall. Please remember the windows are not the cause of the condensation, they are merely an indication of a condensation problem. A family of four in a three-bedroom property can generate as much as 18 gallons of water per week as a result of cooking, bathing and by drying clothes indoors. With double glazed windows and doors and no ventilation this moisture becomes trapped within the property and can cause mould growth, commonly seen around windows and external corners of the walls.

Internal condensation is more likely in the winter months. This happens when moisture in the air contacts a surface whose temperature is lower than the dew point (the temperature in which air manufactures dew).

Condensation can only be controlled, but there are some steps that you can take to reduce your indoor humidity level.

One way is to make sure that all appliances requiring a vent (for example tumble dryers) are vented properly. Avoid using gas heaters (these produce a lot of moisture) and install extractor fans. Extractor fans are an excellent way to increase the air flow and reduce humidity if installed correctly. Another option is to make sure that your home is properly vented.

Why do I have condensation on the outside pane of glass?

The temperature of a typical double glazed window is usually above that of the exterior night time air because of the heat flow from the warm interior of the building. But if the unit has a very low U-Value (thermal conductivity) from the use of a low emissivity coating and Argon gas - then on a still air night, the temperature of the outer glass surface can easily fall below the exterior air temperature or even its dew point temperature. When the glass temperature falls below the dew point temperature condensation occurs. This condensation will not evaporate until the glass is heated by wind, sunlight or heat transfer from inside your house. Our triple glazed windows will suffer external condensation, as they are very thermally efficient! In short the more efficient the windows are, the likelyhood of external condensation will rise!

Condensation between the panes of glass?

Unfortunately this means the seal on the glass unit has failed. The easiest solution is to replace the glass unit, a very simple task on modern glazing that has a beaded system. BJH offer a free measuring and quoting service. All old glass units are sorted and skipped for recycling.