bifold door condensation

[andy183]

Hi, I've had a triple glazed aluminum bifold door installed.

The doors work great, however I've noticed that just on the underside of the frame on which the doors hang that I have condensation. I am fitting a engineered wood floor which will come up to the edge of the frame. It will be hiding this space so once it is installed I will not be able to see the underside of the bifold. I've included a photo that shows the gap (for some reason it is upside down)

I am worried that this gap and the condensation will lead to problems in the future. e.g mould etc.

Does anyone have any suggestions on how to overcome this issue?

Untitled

• andy183
• 23 Nov 2014
• 1

 

[freddiemercurystwin]

How do you know its condensation and not a leak somewhere? Condensation does not typically appear on the lowest part of the frame. A leak however ........

Are any of the drainage holes/channels blocked?

The obligatory more photos (the right way up) request.

 

[AronSearle]

Yes more pics please.

Is the external ground level higher than the wood flooring, hard to tell in your upside down picture but it looks like it could be?

Pics of...

Inside and outside, front and side{ish} view. Of particular interest will be external cills, seals and threshold details.

Is the wetting only occurring at the base, what about the sides? I would agree with Freddy that condensation is unlikely to occur at *just* the base.

 

[andy183]

Here are some more pics

http://s1242.photobucket.com/user/azt5150/library/?sort=3&page=1

The external ground is lower than wood flooring and the bifold.

 

[AronSearle]

Could be condensation as there appears to be no foam filler under the door, not really sure it is myself. Does the internal wetting coincide with wet weather.

Look at the running track on the bottom at the cill threshold. The way the door is detailed means water can get into that, does this channel have drainage and where does it drain to? Is there a gap under the cill on the outside, or is the mortar line tight to the underside. Lastly check that water cannot penetrate the joint where the metal channel meets the timber frame.

If water isn't getting in through that area then condensation is more likely, foam fill that gap.


As an aside, what kind of weather performance is expected from the door, it has no pressure relief grooves or drip details. The seal on the edge where the doors fold together and meet goes under the hinges, it will be fine for a typical back garden in a sheltered location, but wind driven rain in exposed locations may breach the seals.

 

[andy183]

Could be condensation as there appears to be no foam filler under the door, not really sure it is myself. Does the internal wetting coincide with wet weather.

There is definitely no foam under the floor. It is just open to the air. I don't think it does coincide with wet weather. It seems to be when we have the central heating on max and the temperate difference is highest between outdoors and indoors. The only other thing that occurs to me is that we have had the room painted and the floor has been drying out so their is also lots of internal water.

Look at the running track on the bottom at the cill threshold. The way the door is detailed means water can get into that, does this channel have drainage and where does it drain to?

The bifold doors have a drainage cill that lets any water in the drain away to the outside out of the bottom track

Is there a gap under the cill on the outside, or is the mortar line tight to the underside. Lastly check that water cannot penetrate the joint where the metal channel meets the timber frame.

If water isn't getting in through that area then condensation is more likely, foam fill that gap.

Thanks for the advice. Stupid question from me, how does the foam prevent condensation?

As an aside, what kind of weather performance is expected from the door, it has no pressure relief grooves or drip details. The seal on the edge where the doors fold together and meet goes under the hinges, it will be fine for a typical back garden in a sheltered location, but wind driven rain in exposed locations may breach the seals.

The door is in a back garden and very sheltered by trees etc.

Here is the actual door that I have.

https://www.vufold.co.uk/external-bifold-doors/ultra-folding-doors/12ft-grey-aluminium-and-oak

 

[Gazman16]

A few things Ive spotted:
1. Where is the DPC level on your house?
It looks like the underside of the cill has been rendered right upto the frame, Although this looks nice and neat it is a cold bridge.
2. Ideally the cill should over hang the brickwork my a minimum of 25mm. This combined with the high ground level (ideally 300mm minimum) could just be causing moisture to soak through.

I would start by using expanding foam in the gap under the frame. Check that where the cill meets the brick is well sealed with silicone and get a few coats of waterproofer on the bricks below the cill.

 

[AronSearle]

The bifold doors have a drainage cill that lets any water in the drain away to the outside out of the bottom track

Yes I see in your link now.

https://www.vufold.co.uk/media/manuals/ultra/vufold-installation-ultra-12.pdf

Page 8

It is hard to tell from your pictures if they have left a gap at the drainage channel outlet under the cill, if they have it looks tight. If in doubt put a small amount of water into the groove and make sure you see it dripping out under the cill. My concern is that it is not running out clear, and may be working it's way backwards.

how does the foam prevent condensation?

If you look at the cill detail on page 8 of that document, you will see they carry the alloy through the frame with no thermal break. So there is a cold surface in that void under the door, cold surface = condensation. It is also likely you see the back of the outer leaf of uninsulated brickwork under the door. Foam filler will help to reduce the cold bridge and so reduce or eliminate condensation. It should be there already, looks like you still have work going on? Make sure they have also foam filled or otherwise in the cavity around the frame generally when it was installed.

 

[andy183]

I spoke to the bifold people where where actually really helpful. They said they hadn't seen condensation in that part of the door previously.

Looks like the builder when he installed the frame didn't take into account the weep holes which are on the bottom track. The water has no were to go as they are blocked by cement and brick.

The fix appears to be to just drill holes in line with the weep holes to allow the water to escape.

 

[andy183]

A few things Ive spotted:
1. Where is the DPC level on your house?
It looks like the underside of the cill has been rendered right upto the frame, Although this looks nice and neat it is a cold bridge.
2. Ideally the cill should over hang the brickwork my a minimum of 25mm. This combined with the high ground level (ideally 300mm minimum) could just be causing moisture to soak through.

I would start by using expanding foam in the gap under the frame. Check that where the cill meets the brick is well sealed with silicone and get a few coats of waterproofer on the bricks below the cill.

The dpm is one brick course below the door. Where the cil meets the brick is actually cemented. I'm going to put in expanding foam under the gap as a precaution and apply some waterproofer liquid myself.