Double Glazing Condensation

Do you have trickle vents on your windows? If not then you need to crack open the window a little bit whenever you can to improve the airflow. Also, do you dry clothes near or in the room?
 
Trickle vents open in the windows 24/7 (throughout the house), we use the downstairs bathroom mostly (which is vented to outside), and the kitchen is well away from the bedrooms (and also vented). We have a gas fire, although it hasn't been on for ages and it isn't flueless.

"You want to try to avoid too much airflow in that area " - interesting. Given that the window doesn't seal properly, there is a draft all around it. Could this be making the problem worse?
 
jamief said:
Trickle vents open in the windows 24/7 (throughout the house), we use the downstairs bathroom mostly (which is vented to outside), and the kitchen is well away from the bedrooms (and also vented). We have a gas fire, although it hasn't been on for ages and it isn't flueless.

"You want to try to avoid too much airflow in that area " - interesting. Given that the window doesn't seal properly, there is a draft all around it. Could this be making the problem worse?
Click to expand...

It depends, if its cold dry air from outside getting in then wont be making much diff, but if the air from outside is causing lots of warm air to travel to that position then when the air cools it drops moisture.
 
I think I'll see how I get on with the dehumidifier and leaving the kids door open overnight. Failing that, the window does need replaced.
 
jamief said:
I think I'll see how I get on with the dehumidifier and leaving the kids door open overnight. Failing that, the window does need replaced.
Click to expand...

As a temporary solution, get some wide white pvc insulation tape (40mm wide) and tape around the gaps on the 'leaky' window. This prevents it from opening but will eliminate the drafts. We have a similar problem in 2 of the bedrooms in our place and are not in a position yet to change the windows (as we want to do them all at the same time, £££!). We still have top windows that open, but they dont leak only the big windows leak.
 
jamief said:
I think I'll see how I get on with the dehumidifier and leaving the kids door open overnight. Failing that, the window does need replaced.
Click to expand...

Some of the suggestions in this thread have been ridiculous. Here's what I'd do.

Leave the kids door wide open 24/7. If after 3 days you still have an issue buy a dehumidifier or turn your heating up a little.

What temperature is your thermostat on at? How is the radiator in their bedroom? How warm is it in their bedroom?

There is no way I'd be looking at vents or replacing the window without looking at all the zero cost options first and foremost.

Half of your breath is basically moisture. 2 kids in a small room will make a lot of moisture. you need to combat it with heat and airflow. So door must remain open at all times, especially if they are in the room to let the moisture get out the room. It must not be too cold in their room to allow the moisture to evaporate and find a way to disperse (which is why airflow and temperature is key).
 
condensation is where hot moist air hits cold air

it is normal for air in houses to be more humid

I think your on the right track with the window gaps, tape them and see
 
Turning the heating up will make no diff if its allowed to go super low at night, ie if the house insulation is bad.
Higher heat increases the airs ability to hold moisture, as soon as it cools it will lose that.
You would have to keep the temp going higher and higher to give it room to absorb some more moisture.

Interestingly dry air also warms faster (lots of energy to heat water) so a hidden benefit of dehums is that it feels like your heating works better. But equally it will seem to cool quicker as well (less stored heat)

Also just a note to remember that the fire service do not recommend sleeping in a room with an open door. If its closed and there is a fire in house you will be alerted likely before practically any smoke is in the room, if the room door is open then it can fill really quickly (fire dependant of course). If you do go with open doors I would ensure that you have good detectors so that you have maximum time to react should the worst happen.
Us site, quick google didnt turn up the UK one. Interesting fact is you are also recommended to have a smoke alarm in any room you sleep in. I bet most of us fail on that, which considering the cost of a basic smoke alarm is pretty poor oversight

http://www.nfpa.org/News-and-Resear...sed-to-best-protect-themselves-in-a-home-fire
 
As a kitchen fitter i come across houses with bad condensation problems all the time. Quite often when we rip out an old kitchen out there will be black mould on the walls behind kitchen cabinets.
The vast majority of houses that have this problem are Victorian, 1930's houses and houses built up until the very late 1960's. They all share one thing in common, either no cavity wall at all or where there is a cavity wall (1960's onwards) there is no cavity wall insulation. If there is no cavity (Victorian and 1930's houses) the external walls will always be cold in winter, but because there is no cavity the internal walls will always be cold as well. For latter houses with a cavity but no cavity insulation, the problem is the same but just takes longer before the inside wall becomes as cold as the external wall.
What type of house do you have OP ?
 
I fit Mechanical Ventilation & Heat Recovery Units and Positive Input Ventilation Units as part of my job as an electrician.

A lot of houses have poor ventilation, this is due to the retrofitting of cavity wall and loft insulation, so damp air is struggling to escape the house due to them becoming more air tight.

As the damp air cools it find the coldest spot, the windows, and clings to it. Window trickle vents aren't going to do enough. If you actually do the calculations for how many people are in the house, how much moisture is being produced and how much the trickle vents can move then you'll find them woefully inadequate.

My recommendation would be to install a PIV unit. These things take the air from your loft and filter it, some have comfort heaters too, then they blow this around the house. You will find that a PIV will all but eliminate condensation problems by keeping a constant supply of clean dry air moving around the house.

PIV units start from about £300 for a Nuaire unit and the Enviro-Vent and Vent Axia units can go past £500 for the higher spec ones.

If you are comfortable with fitting a fused spur in your loft taken from a lighting circuit then it is something you can install yourself to save the cost of having a specialist do it. It would take little over an hour to get done, the hardest part is cutting a large hole in the ceiling for the ducting.
 
Thank you - interesting read. Our house was built about 1925 and either has no cavities, or they are incredibly small, so no CW insulation. These PIV units - look interesting, do you typically have one per house? I'll also look into taping the window - it would at least rule out the leaky window as being the issue (or not).
 
Sounds like you are trying your best RE the airflow but I would recommend a Nuaire PIV.

Latest eco models add some nice features. Constant fresh, warm air flow around the house. Just read the amazon reviews from people with really bad condensation.
 
topgun06 said:
Does it work well, easy to install? What did you wire it up to?

I've looked at these in the past. But I should first start by installing extractor fans in my bathroom and kitchen, as at the moment we have to open the windows, and in the winter months, it is freezing!
Click to expand...
Yes it works well and relatively easy to install. I didn't do the wiring however as said previous its effectively a fused spur off lighting socket.
I posted some pics in this thread
https://forums.overclockers.co.uk/threads/bungalow-build-log.18757204/page-3
 
TallPaul1878 said:
I fit Mechanical Ventilation & Heat Recovery Units and Positive Input Ventilation Units as part of my job as an electrician.

A lot of houses have poor ventilation, this is due to the retrofitting of cavity wall and loft insulation, so damp air is struggling to escape the house due to them becoming more air tight.

As the damp air cools it find the coldest spot, the windows, and clings to it. Window trickle vents aren't going to do enough. If you actually do the calculations for how many people are in the house, how much moisture is being produced and how much the trickle vents can move then you'll find them woefully inadequate.

My recommendation would be to install a PIV unit. These things take the air from your loft and filter it, some have comfort heaters too, then they blow this around the house. You will find that a PIV will all but eliminate condensation problems by keeping a constant supply of clean dry air moving around the house.

PIV units start from about £300 for a Nuaire unit and the Enviro-Vent and Vent Axia units can go past £500 for the higher spec ones.

If you are comfortable with fitting a fused spur in your loft taken from a lighting circuit then it is something you can install yourself to save the cost of having a specialist do it. It would take little over an hour to get done, the hardest part is cutting a large hole in the ceiling for the ducting.
Click to expand...

We are about to have a PIV system fitted, 60s detached bungalow with all the trappings to make it condensation hell - double glazed, cavity & loft insulation with 3 of the 4 fireplaces blocked off!

What is the difference between envirovent and nuaire in your experience, money to a degree is not an issue as just want a long term solution?

Do you recommend the heat versions, is it ok to insulate around them?

Don’t suppose you work on Norfolk area, struggling to find installers with knowledge of the products!?
 
Shimmyhill said:
We are about to have a PIV system fitted, 60s detached bungalow with all the trappings to make it condensation hell - double glazed, cavity & loft insulation with 3 of the 4 fireplaces blocked off!

What is the difference between envirovent and nuaire in your experience, money to a degree is not an issue as just want a long term solution?

Do you recommend the heat versions, is it ok to insulate around them?

Don’t suppose you work on Norfolk area, struggling to find installers with knowledge of the products!?
Click to expand...
I'm in the North West sorry. If you contact Enviro-Vent they will put you in touch with a qualified installer.

The PIV unit would be situated above the loft insulation, either on a platform or suspended from the roof beams. I took my course at Enviro-Vent so obviously they pushed their own products whilst I was there but in my experience the Nuaire brand is perfectly fine.

The price difference comes down to built in functions. Enviro-Vent have better filters, the unit is more compact and it has a lot more sensors so it ramps up if it detects the house humidity is getting too high. The MIVs are multi room, so rather than having one large duct in the landing that moves air around the property it has a number of smaller ducts that can be directed into a couple of rooms.

A comfort heater just takes the chill off the air from the loft, it's not important but it's a nice feature. Some customers complain that the house becomes colder but really that's just the sensation of air moving around and, as a previous poster has mentioned, drier air heats up much faster so there is a considerable energy saving there.

In a bungalow an MVHR unit is an option. They both extract and supply the air from a property, removing damp air and recycling the heat through a heat exchange chamber to warm the incoming air that is taken from outside. These come at a significant cost though and I usually only recommend these as part of a full refurbishment.
 
Another vote here for the nuaire drimaster.

I had one installed last month and it has dropped our Relative Humidity upstairs from mid 70s to mid 40s.

Just make sure you've got ventilation in the loft. We never had an issue with condensation in ours but I still got some felt lap vents to make sure.
 
You must log in or register to reply here.
Back
Top Bottom