single brick skin porch condensation/damp

1 Jan 2010
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United Kingdom
I have a porch with a pitched roof, built on the outside of the house and it is single brick skin construction. It used to be open (ie just covered space) with only an inner front door (between porch and main house). Recently, in order to create more 'inside' space, we put a new front door on the outside of the porch space.
The problem inevitably, is that with this cold weather the inner walls of the new enclosed porch stream with condensation and shoes/coats go moldy. The house is exposed brickwork so I can't externally render the porch without it being totally out of character. I intend to paint the outside with Thompsons water seal, but it is really an inside treatment that won't take up too much space that I need. I'm putting a small radiator in this weekend to keep the temperature up, but i think this might make the condensation problem even worse.

It's only a porch, so I'm not really bothered about warmth - just need to keep it dry.

any ideas? [/b]
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Are you saying that the outside door is now located on the porch and that there is no door separating the porch from habitable?

When is porch not a porch? When it is an extension.:cool:
No, there is now an internal glazed door between porch and habitable house. Sometimes we leave this open for air'flow, but as the porch is so cold, this lets in cold air to the house.

Thnaks for your swift reply by the way!
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Thanks hotrod, :eek: , is that right? I hadn't thought of that. But will that stop condensation in the porch? I suppose the theory being the porch will not then draw heat in from the main house (which is causing the condensation)?. It will effectively become a cold porch - but dry - a separate 'space'.

How will the new rad in the porch effect this?

This all reminds me of physics at school!
a single skinned porch, probably with an uninsulated roof and floor, is always going to be cold. If you let warm moist air from the house into it, it will be damp as well. Best thing is to treat it as outdoors, ventilate it on both sides so that cold dry air can flow through. That will sort out the condensation. You need to keep the house/porch door shut and draughtstripped to prevent cold air coming in or moist air going out.
All very useful tips here guys, thanks a lot. I will put theory into practice in next few days!!
Any other advice always welcome!
Thanks hotrod, :eek: , is that right? I hadn't thought of that.

Yes, it should be an exterior grade door and frame with appropriate draughtproofing to 'seal' the house from the porch. Otherwise, the porch becomes an extension of the dwelling from a Building Regulations POV and therefore subject to the regulatory requirements of The Building Regulations. ;)
makes sense when you think about it...and the tip about building regs is right too. I should know that really...being a construction project manager!! oops. (more industrial though to be fair!!)
Hi guys, I know this is an old thread but I found it through google. Instead of making a new thread I thought I may aswell continue here, I have the EXACT same issue as the original poster.

After reading the comments I will be installing 2 vents in the porch but can anyone recommend a good paint that will not go mouldy/show condensation? Am I right in thinking something like sandtex exterior paint would be suitable?

Also what size vent should I be fitting I was thinking 4" like they use to vent a tumble dryer and then a set of grills for inside/outside? or would that be too much?

Any other help/suggestions would be appreciated thoroughly fed up of the 'mouldy' porch now!

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