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Aerial view of a construction site with two ground slabs, one freshly cast, one with walls starting to rise, photo

24 August 20266 min read

Basement or Ground Slab: Soil, Groundwater and the Decision Before the Building Application

The ground under your plot decides between basement and slab before your budget does. Why groundwater south east of Berlin matters, when the waterproof concrete tank becomes mandatory and what actually drives the cost.

New buildShell construction

Shell of a house with brick masonry, scaffolding and a timber roof truss on a construction site, photo

17 August 20266 min read

Masonry house or prefab: build time, warranty and what your plot dictates

Both methods get you a finished house. The decision comes down to your plot, how long you can still change details during construction, and who stands in front of you when a defect needs fixing.

New buildPlanning

Renovated late-19th-century facade with stucco ornament, timber windows and a converted roof storey next to unrenovated period buildings, photo

10 August 20266 min read

Renovating a listed building: consent, typical conditions and the Denkmal-AfA tax break

Which consent has to be in place before the first measure, what the heritage authority requires for facade, windows and roof, and how the Denkmal-AfA lets you write off the renovation costs.

RenovationListed buildings

Door on an escape route with an exit sign and escape route pictogram, photo

3 August 20267 min read

Structural Fire Protection: Building Classes, Fire Resistance and the Proof in Your Building Application

Whether a wall must withstand fire for 30 or 90 minutes depends on the building class. What structural fire protection means for design, permits and costs, from new builds to conversions.

Fire ProtectionPlanning

Stripped-out floor with bare concrete walls, construction dust and steel props on a renovation site, photo

27 July 20266 min read

Gut renovation of an older building: sequence, hazardous materials and costs

From strip-out to handover: what has to be settled before the first demolition hammer, in what order a gut renovation runs and which items drive the cost in an older building.

RenovationOlder buildings

Bricklayer laying concrete blocks with trowel and mortar on a shell wall, photo

20 July 20266 min read

The structural shell: trades, sequence and duration from excavation to topping out

From the batter boards to the topping-out ceremony: which trades build the shell, in what order the steps follow each other and which factors drive duration and cost, with a focus on construction sites in Berlin and Brandenburg.

Structural shellConstruction sequence

Masonry shell of a house extension under construction

15 July 20266 min read

Adding an Extension to Your House: Permits, Structure and Costs in Berlin and Brandenburg

An extension adds living space on the plot you already own. What the development plan allows, why the junction with the existing building is the real task, and which factors drive the costs.

ExtensionBuilding in Existing Stock

Modern detached single-family house, new build, in daylight, photo

6 July 20265 min read

KfW Funding for New Builds 2026: Programmes 297, 298 and 300 at a Glance

KfW 297, 298 or 300? All three new-build programmes for 2026 require Efficiency House 40 but differ in loan limits and target group.

FundingNew Build

Photovoltaic panels on a building roof as a symbol of energy renovation, photo

1 July 20266 min read

Heating Grants 2026: KfW 458 and the 21 July Deadline

KfW 458 covers up to 70 % of a heating replacement. From 21 July 2026 the maximum drops to 19,600 €. Why the application has to come before the contract.

FundingHeating