Condensation in a Concrete Built Porch

[sorethumb]

Ok Porch has no heating and is already condensating in the mornings. No window vents and no Air block and no heating in it,.

Porch is double glaszed and main door to house in in porch. Internal door between porch and house. Condesation get worse when you open the internal door into the porch to get shoes/ mail/ go out door. If I go out at 6am then it is condensated by 7:30 when G/F goes out....

What is the best options to stop this and stop Condensation and Damp would a heater help>?

 

[Static]

Leave the exterior door open or lower the temperature in your house to the same as in the porch..

In all seriousness you should put in some ventilation in the porch to keep the condension under control..

 

[ajrobb]

As Static says, ventilation. You also want to keep out warm moist air from the house, so fit draught excluder to the internal door. I've just added a ventilator to a similar porch and, after a couple of weeks, the musty smell finally went.

I'd also worry about whether you have adequate ventilation in the house. Check for mould behind large items of furniture against outside walls.

Yes, a heater would help but I went for ventilation instead.

 

[foxhole]

A heater is of no use to prevent condensation, makes things worse if the air is warm as it can hold even more moisture.Ventilation is only solution.

 

[ajrobb]

A heater is of no use to prevent condensation, makes things worse if the air is warm as it can hold even more moisture.Ventilation is only solution.

As the porch is not inhabited, a heater will help raise surface temperatures above dew point. Shop windows use local heaters to keep the windows clear. HOWEVER, if the porch is full of wet wellies and coats, yes, a heater will make things worse.

Ventilation is the preferred solution.

A dehumidifier would also work but is overkill unless the porch is used for drying coats etc.

 

[foxhole]

A heater is of no use to prevent condensation, makes things worse if the air is warm as it can hold even more moisture.Ventilation is only solution.

As the porch is not inhabited, a heater will help raise surface temperatures above dew point. Shop windows use local heaters to keep the windows clear. HOWEVER, if the porch is full of wet wellies and coats, yes, a heater will make things worse.

Ventilation is the preferred solution.

A dehumidifier would also work but is overkill unless the porch is used for drying coats etc.

Don't agree on either point.

 

[sorethumb]

Leave the exterior door open..

This would pose a bit of a scurity problem as the door Exterior door on the porch is the security door leaving it open would then allow "MR Bulglar" to walk in though a interion door.. This option is not an option.

I take it that the condensation / steaming up of the windows is the warm are meeting the cold glass. To stop this I take it we are recommending stopping the heat getting into the porch. However the porch is the path in and out of the house.

Ventalation - As the windows & door are UPVC and were fitted with no vents. What is the best way to ventilate the porch. How would I fit a vent?

 

[Richard C]

Weve only just gone through all of this, read almost identical thread;
//www.diynot.com/forums/viewtopic.php?t=241780&highlight=

 

[foxhole]

Weve only just gone through all of this, read almost identical thread;
//www.diynot.com/forums/viewtopic.php?t=241780&highlight=[/QUOTE]Problem is people want to use the porch as something it is not, an internal room.

 

[Richard C]

Why have you transferred your post to the thread I linked as a reference for you, you’ll cause all sorts of confusion.

Mmm Great solution not Shame I want to use this space for storage of ackets and boots ect dogs leads, so they are not in the hall dripping on carpet etc. I think when winter comes you solution would allow the water on jackets / floor etc just to freeze up.

A properly built & insulated porch will be cold but won’t freeze up & certainly won’t be damp; if you want to store/dry damp clothing in there you will certainly need ventilation in there; your failing to grasp what causes condensation in the first place.

Anyway I particually don;t want a "External Door" between the porch and the house. That to me would be defeatest becasue if I make the joining door an External door then the porch becomes "outside" so whats the point of the "porch"

A porch is not supposed to be inside, that’s the whole point; are you aware current Building Regulations require an external insulation grade door between the main property & the porch or it is no longer a porch but an extension which means the whole lot must comply with Building Regs. Likewise, any heating in there must be capable of being independently controlled & isolated to comply with BR’s.

As foxhole states, a porch is to provide a second barrier to wind and heat loss, that's all it's for.

 

[ajrobb]

if you want to store/dry damp clothing in there you will certainly need ventilation in there

I agree with RC, with wet coats you MUST have ventilation. Whether you have heating as well to help them dry is another matter. With double glazing in the porch and a single-glazed door to the house, you are going to get some heat coming from the house. I think you ought to seal the internal door to prevent more moisture escaping into the porch from the warm house.

On cold mornings, the outside relative humidity is often 100% and dew forms outside. We often get dew on the outside of our double glazing. Too much ventilation (like leaving the exterior door open) and the porch can suffer from the same dew. You need some heat to raise the surface temperatures above dew point.

Warm air in the house has much more moisture than outside (even when dew is forming outside), it is just that the warmer surfaces in the house are normally above the internal dew point temperature.

Your porch suffers condensation because it is neither warm nor dry. The easiest way to dry it is to isolate it from the moist air in the house and to ventilate it to the drier air outside. Currently, it is the wrong way round; the double glazing seals it from the outside and the internal door lets moisture out from the house into the porch. That is all before you add wet coats...

 

[sorethumb]

A porch is not supposed to be inside, that’s the whole point; are you aware current Building Regulations require an external insulation grade door between the main property & the porch or it is no longer a porch but an extension which means the whole lot must comply with Building Regs. Likewise, any heating in there must be capable of being independently controlled & isolated to comply with BR’s.

Ahh but this is an existing porch been on the property for many years, It is Termed a porch, well that what I call it, but is tied into the main roof with slate. Therefore we are not looking at a new build property. The heart of the property was built in 1798 and the extensions were 1900 through to 1980. Porch probably is about 40 years old.

 

[Nige F]

Leave the exterior door open..

This would pose a bit of a scurity problem Ventalation -

Leave the letter box open