ᐅ Patio doors with a low threshold

Hm, for example, we had the problem of water penetration with our "old" balcony door despite having a 15cm (6 inches) threshold.

Of course, water should not be standing against the glass, but I don’t necessarily consider water penetration during heavy rain to be the most important factor for or against a low threshold...

Hello Doc,

Doc.Schnaggls schrieb:

Of course, water shouldn’t be standing directly on the glass, but I don’t necessarily consider water ingress during heavy rain to be the most important criterion for or against a low threshold...

It should be, because "derstefanm" and the window installer of the parents are quite right. In "nordanney’s" case it’s probably not an issue, since there is enough space under the bangkirai wood for the water to drain away.

There are several window installers – including ours – who explicitly point out this problem and require to be released from liability in case their concerns occur. According to DIN 18195, the threshold must be at least 15 cm (6 inches) above the finished floor – that means above the terrace. This can be reduced to 5 cm (2 inches) if a drainage channel with a discharge into the sewer is installed or if the terrace is covered.

From practical experience: some time ago, we visited a used property where a balcony was built on one side of the attic and the access to the adjacent room was sealed off with a door threshold (sliding door). Despite the balcony being covered, water was standing inside the room; this was very clearly visible because the building still had night storage heaters installed in recesses behind the glass.

By the way, why was an exterior window sill installed on the terrace door of your construction project?

Regards, Bauexperte

BeHaElJa schrieb:
There is also something else – new construction thresholds. Look it up on Google, they look different.

I checked Google myself but didn’t get much clearer. Is it about having no thresholds at all? Do you have any specific source or picture so I can better understand what it looks like?

derstefanm schrieb:
The window installer who fitted the doors and windows in my parents’ extension said that if you install a door with a low threshold, there is no warranty covering water ingress from heavy rain.

Our builder brought up the same topic. But he didn’t mention anything about warranty exclusions. He said we need to use different window profiles, MD 90 instead of MD 82. These are designed to withstand weather exposure permanently. A proper drainage system on the terrace would also be necessary.

Regards,
Alex

@Bauexperte: Our terrace is open on three sides, and along the edges it steps down in two levels by just under 2 meters (6.5 feet). With this design, I can't imagine water ever accumulating on the terrace high enough to press against the door.

The exterior window sill was installed as standard in our build—below it there is a gravel layer with drainage to keep moisture away from the house wall.

Is this unusual?

Regards,

Dirk

Hello Dirk,

Doc.Schnaggls schrieb:
@Bauexperte : Our terrace is open on three sides, and the edges drop down in two steps by nearly 2 meters (6.5 feet). With this construction method, I can’t imagine the water on the terrace ever rising high enough to push against the door.

It depends on the substructure and the slope, that’s what I would say. However, I assume your provider’s subcontractor would not take any risks, and that the substructure including the slope is correct.

Doc.Schnaggls schrieb:

The exterior window sill was installed as standard in our case – underneath there is a gravel bed with drainage to keep moisture away from the house wall.
Is this unusual?

Yes. Normally, the terrace surface is extended into the recess instead of installing a window sill there. That is why in our ground floor design, no window sills are planned at patio doors.

Regards, Bauexperte

We also left out all the window sills at the ground floor terrace doors... The general contractor then gave us a credit of about 1000 € (approximately 1100 USD). We thought it was better than risking them getting warped.