Lift-sliding door or 2 double-wing doors at KFW55

Hello,

we are planning to install a lift-and-slide door in the living room instead of 2 double doors side by side, each having 2 sides that open inwards (I don’t know the name right now).

In the living room, these are the only windows, and on the ground floor there is only one more window in the open kitchen.

What are the advantages and disadvantages of a lift-and-slide door compared to the 2 double doors, also regarding a KfW55 house??

Advantages: Space-saving when open Modern appearance With sufficient opening width, more connection between "Indoors and Outdoors". Disadvantages: More expensive Requires minimum width to be really more effective Possibly complicated opening mechanisms (especially if it is intended to be a lift-, slide-, tilt door) are not easily understood by everyone (children) and are sometimes prone to defects Very heavy at "worthwhile" size (children) Pinching potential, as attention must be paid to other areas (below). This is often not yet learned...

ok thanks

It should only be a lift-and-slide door
the width will be about 5m, so 2.5m per element
Surcharge from the builder: 5000€

Regarding kfW55, there are no major disadvantages?

Is a lift-and-slide door prone to defects?

We definitely also find the lift-and-slide door better
More modern and more window area

In terms of size, it will even get the approval of . But it will also be very heavy and, of course, a strain on the entire mechanism. If it is good quality, then according to my father-in-law, it is not necessarily more prone to defects than "normal" windows. The installation will be hell, but you don't have to do it.

The high surcharge was also explained to me

They say that everything has to be reinforced because the lift-and-slide door will become very heavy for us (triple glazing because of KfW55)
But once it is installed, you can slide it open and closed normally, right?

Installation is not my problem :)

Do you think the surcharge of €5000 is reasonable or is that way too expensive?

Installing it later would of course be much more expensive

The high surcharge was also explained to me.

They say that everything has to be reinforced because the lift-and-slide door is really heavy (triple glazing due to the KfW55).
But once it's installed, you can open and close it normally, right?

Installation is not my problem :)

Do you think the surcharge of €5000 is reasonable or is that way too expensive?

Installing it afterwards would of course be even more expensive.

It's hard to say, since quality also plays a role there. Our lift-and-slide door (width: 3m) costs about €1,500 surcharge.