ᐅ Installing Windows After Construction?

Hello,

we are currently working on renovating our kitchen. The plan is to replace the existing kitchen in about 2 years and also change the layout. We would like to have more natural light and a nice view of the front yard and garden. Our wish is therefore to add an extra window above the kitchen counter, specifically above the sink.

Has anyone had this done before or has experience with this? Could you advise us on how to proceed, what we need to check, and roughly how much it might cost? This would help us include it in our budget planning.

My idea is to go to an architect who can assist with structural issues, submitting applications to the building authority (building permit/planning permission), etc., and then have the work carried out.

How can I find out in advance whether a) it is structurally feasible and b) whether approval is required? Also, what factors would the approval depend on? The distance from the desired window to the property boundary is about 10 meters (33 feet), and the adjacent lot is undeveloped.

How complex is the process—just cut a hole, install the window, finish it nicely, and done?

For your information:
Our exterior wall consists of 30 cm (12 inches) Ytong blocks plus exterior plaster, and the window should be about 1.20 m (4 feet) wide, not floor-to-ceiling.
Directly below the proposed window are water and sewage lines, but this should not be a problem since the window is not floor-to-ceiling.

I appreciate your tips and experiences before I get too attached to the idea of this window and then find out it might not be so straightforward.

By the way, we are located in Lower Saxony.

Jurassic135 schrieb:

How complicated is it? Just cut a hole, put in the window, fix it up nicely, done?

Usually, yes.
Of course, a lintel with proper support on the remaining walls must be installed above the window. This lintel is then insulated on the outside, and the exterior plaster must be applied professionally to avoid any weak points at the junction.

It should be checked beforehand whether there are electrical cables in that area, but unless there is a power outlet directly below, this is generally not the case and is easy to verify.

You don’t need a building permit / planning permission or an architect for this.
Windows only need to be coordinated with neighbors if the distance to the property boundary is very small, which does not apply here.
Having a structural engineer check whether the exterior wall at that point can carry the load over the smaller opening and determine the required lintel width is recommended and won’t hurt.
You will need a bricklayer, a plasterer, and a carpenter or window installer, or skilled professionals in these trades.

Thanks in advance for the reply!

There is an outlet under the desired window (for the dishwasher, about 40 cm (16 inches) high near the water supply and drainage, which is also supposed to be reused), but shouldn’t the connection come from below and not run higher up?

Is it really not necessary to get building permit / planning permission involved at all?
Since it was quite a hassle for our double carport, I find that hard to believe 😀 That would be great...

So, structural engineer, tradespeople, materials.
Would it be possible to manage with just a few thousand euros, or what should one realistically budget?
I know prices vary a lot, but I’d like a rough estimate to include in our savings plan.

I also don’t think you need approval from the building authority for a window, but I would recommend contacting them in advance to check—better to be safe. Otherwise, just get the mason to install the lintel. I assume the mason handles the structural calculations themselves, right? Then the wall needs to be replastered afterward. Do you have no additional insulation, just the Ytong blocks?

I would roughly estimate the cost of a window at around €800 (about $880), but it can of course be significantly more. You can install the window yourself if you want. I have no idea what a tradesperson would charge for that. Inside, you’ll also need to connect the window frame to the plaster again. In my experience, the total would be somewhere in the range of €2,500 to €3,000 (about $2,750 to $3,300). A lot of money and mess for a bit more light.

Jurassic135 schrieb:

Is it really necessary to involve the building authority at all?

If it changes the exterior facade so significantly that it affects the overall appearance of the street. Something along those lines.
This would be the case, for example, if you live in a mid-terrace house where uniformity is required.
Or if you want to add about 6m² (65 sq ft) to a windowless facade facing the street. In that case, I would at least call the building authority.

Isn’t it a semi-detached house in your case? Probably originally built by a developer who, for simplicity and cost reasons, constructed a twin house? However, that doesn’t necessarily mean that uniformity is required. What does your development plan or design guidelines say?

Exactly, it is a semi-detached house. However, the entrance and the kitchen side are located on the side, not at the front, and in our case, they face away from the street and the neighbors at the very back. The new window is practically invisible, especially from the street, so it really shouldn’t concern anyone. There are two semi-detached houses here, so four halves in total; this is not a new development but situated among existing buildings.

The development plan only includes special design regulations for an adjacent area; our section is explicitly exempt from these. Probably because we live between older buildings anyway, and there is no uniform appearance here—new constructions stand next to old farmhouses and 1960s buildings, all mixed together in terms of shapes and colors.