Condensation in peep holes?

We got an expensive PVC door a number of years ago. There's a peep hole but we've never really been able to use it. At this time of year it's particularly bad. All you can see it a big drop of water and as such everything beyond it is distorted.

I googled and someone says the condensation is caused by a temperature difference between the outside and inside of the exterior lens. It says the exterior needs to be properly sealed. I've had a good look at it and it seems well sealed to me! Any ideas how I can remedy this and actually use it?!?!?

MisseyB

Where is the condensation gathering? On the inside of the glass, the outside of the glass or between the two panes of glass?

Thanks for the reply. I think it's on the inside of the exterior lens.

MisseyB

i would have thought that the peep hole should come as a ready sealed unit like double glazing units. Otherwise there would always be the potential for moisture to get in and condensate.

If that's not the case and you've checked the exterior seal then it might be an issue with moisture from the inside. In my experience most homes are very humid, particularly in winter when people air clothes on radiators. You might find that the lovely warm moist air inside is condensating on the cold glass of the exterior lens.

Could you go back to the supplier about it?

I doubt it as we've had the door for donkey's years! I purchased another peep hole on eBay. Hopefully it's just a dodgy one we got for free. Unfortunately I'm not getting my hopes up as the letterbox and other orifices drip with water continuously over the winter.

MisseyB

It definitely sounds like your door doesn't provide a thermal barrier to the cold.

A good expample of a thermal barrier in action is a styrofoam cups full of ice on a warm day. Even with the difference in temperature between the ice and the air the insulative properties of the styrofoam prevents condensation. Try the same thing with a glass and it'll be full of condensation.

If you can't improve the insulative properties of the door you might try reducing the humidity in the air in the vicinity of the door. You could to this by venitlating the space or by restricting the movement of moisture around the house. You could do this by closing bathroom and kitchen doors and making sure no wet clothes go on radiators in the room with the door.