Condensation in conservatory with glass roof

JG54

Hi 
I recently have replaced my old conservatory with poly roof replaced for a glass roof one.

Any advise on what will help with the condensation build up at night on the glass roof? 

Would a trickle vent be beneficial? Conservatory is 3mx4m attached to open kitchen with brick wall left n right.

Any suggestion/ advice would be welcome. 

grumbler

Are you saying that that there is no door between the kitchen and the conservatory and there was no condensation with polycarbonate roof?

This is hard to believe.

JG54

grumbler said:

Are you saying that that there is no door between the kitchen and the conservatory and there was no condensation with polycarbonate roof?

This is hard to believe.

Hi, yes that is what I am saying. I have put up with the old poly roof for 10 years which was already there when I moved in. 

Could it be because the conservatory is still too new with plaster and cement floor? The cement was laid 5-6 weeks ago. The walls plastered last week.

grumbler

Yes, this is possible.

Bendy_House

It's also quite likely that the old poly roof had numerous draught gaps in it which kept it dry!

Have the kitchen doors been removed permanently? If not, the simple cure would be to close these doors at night, and leave a couple of conservatory windows on vent setting overnight - sorted.

If the doors are no longer there, then the solution is still to vent the room, but that will mean the kitchen will be a bit colder too.

Just have the heating set to prevent the house becoming too cold overnight - say at 12-14oC - and then coming on a good half hour before you get up. As soon as you're up, close the venting windows in the kitchen/connie - job done.

If a main part of the cause is the water still coming out of the plaster and concrete, then you can expect the situation to improve over the next month or so. But there's an equal chance the cond is from the kitchen and living areas - the glass roof is simply one of the coldest parts in that whole area.

JG54

Bendy_House said:

It's also quite likely that the old poly roof had numerous draught gaps in it which kept it dry!

Have the kitchen doors been removed permanently? If not, the simple cure would be to close these doors at night, and leave a couple of conservatory windows on vent setting overnight - sorted.

If the doors are no longer there, then the solution is still to vent the room, but that will mean the kitchen will be a bit colder too.

Just have the heating set to prevent the house becoming too cold overnight - say at 12-14oC - and then coming on a good half hour before you get up. As soon as you're up, close the venting windows in the kitchen/connie - job done.

If a main part of the cause is the water still coming out of the plaster and concrete, then you can expect the situation to improve over the next month or so. But there's an equal chance the cond is from the kitchen and living areas - the glass roof is simply one of the coldest parts in that whole area.

Thanks and you are right. The poly roof already had gaps and was leaking hence the replacement to glass and brick walls.

The house already came with the conservatory open to the kitchen - not doors between them. The kitchen itself is a double story extension and has glass doors to the main living area.

can I ask what windows on vent setting is? If I don’t have this would a trickle vent help? Not too sure if it is too late to install one.

Bendy_House

Most windows have a 'vent' setting that has it 'cracked' open around 10mm, and can be locked in that position to keep it secure. If yours don't have that, then adding trickle vents should do a similar job. Not sure how easy it is to fit them, tho'.

I think I'd be reluctant to fit retrospective trickle vents, at least not unless they are unobtrusive and reasonably priced.

For the time being, at least, I think I'd just wait and see if the amount of cond falls away as the extension is finished off - it might do.

What you could do to almost certainly help is, once the heating has gone off for the night, open some windows in the extension a couple of inches, and let it vent while you get ready for bed. Then just close them (for security) before you retire. A half-hour venting will likely help, a bit at least...

Most cond forms overnight, of course, as the house temp falls and the cooler air can no longer hold on to the moisture in it. That's why a small amount of overnight ventilating is the most effective - it clears it as it tries to form.

Doozergirl

Bendy_House said:

Most windows have a 'vent' setting that has it 'cracked' open around 10mm, and can be locked in that position to keep it secure. If yours don't have that, then adding trickle vents should do a similar job. Not sure how easy it is to fit them, tho'.

I think I'd be reluctant to fit retrospective trickle vents, at least not unless they are unobtrusive and reasonably priced.

For the time being, at least, I think I'd just wait and see if the amount of cond falls away as the extension is finished off - it might do.

What you could do to almost certainly help is, once the heating has gone off for the night, open some windows in the extension a couple of inches, and let it vent while you get ready for bed. Then just close them (for security) before you retire. A half-hour venting will likely help, a bit at least...

Most cond forms overnight, of course, as the house temp falls and the cooler air can no longer hold on to the moisture in it. That's why a small amount of overnight ventilating is the most effective - it clears it as it tries to form.

Trickle vents *are* cheap and unobtrusive. 

Imagine how much water goes into cement and plaster, OP.  It's a lot and it takes a long time to dry - about a month per inch of concrete.  Even paint has a massive water content.  That is your main issue at the moment, it's just drying out.  You can get a dehumidifier to help the process along.  

Then it is entirely possible that your new roof is more airtight than your old
one and doesn't allow as much moisture to escape, in which case you will
need to manage ventilation better once the room has dried out.  

JG54

Yes! I have discovered that the side windows have the vent setting hence I leave them on that setting during night. Will that act as a trickle vent? 

I have the conservatory doors open during the whole day plus windows. 

Omg! Have done the snagging and it is bad. Poor craftsmanship. 

greenface2

vent as much as possible while the conny dries . trickle vent the openers on a night latch when you can and if you feel safe to go out or bed on a night latch . glass is still better than poly carb but imaging the heat and steam coming from your kitchen the glass no matter how good thermal values isn't as good as the rest of the building and moisture collects on cold spots 

Bendy_House

JG54 said:

Yes! I have discovered that the side windows have the vent setting hence I leave them on that setting during night. Will that act as a trickle vent? 

Yes, a very good trickle vent

I bet you'll find a dramatic difference the next morning after you leave these cracked open.