ᐅ Terrace House Upper Floor Extension

The ground floor will be occupied during the renovation, so the work should not be noticeable there. The wish was for a transversal gable (4 m (13 feet)) starting from the ridge towards the south, extending over the elevated terrace on the right side of the house. The basement exterior stairs come up on the left side. The south side has two rooms. The attic is used as a bedroom.

We have submitted a preliminary drawing, but the building authority requires a gable in the middle. Use of the attic is not possible. There is still a chimney in the center of the house.

On the upper floor, we have about 48 m2 (516 sq ft) of living space. Which would be more cost-effective: attaching a separate concrete box that does not fit structurally, or adding two north-south dormers with a maximum width of 3 m (10 feet)?

For rough cost estimates, we would be grateful. The roof structure needs to be stabilized and insulated: collar beam roof.

We would appreciate any ideas.

[quote="Windfange, post: 34159"]

We would appreciate rough cost estimates..

Somewhere between 20,000 € and 150,000 €, but it can also be more expensive........ 😎

Let me ask in a different way: which could be more cost-effective, an extension built with a timber frame or brick construction?

Also, has anyone ever extended a suburban house with an L-shaped addition? We only wanted one more room on the upper floor, so we had the (rejected) idea of sleeping in the attic. Now we are considering adding about 4 x 4 m (13 x 13 feet)...

Attached is the drawing of our requested renovation that was rejected