Building permit documentation for a holiday house, Račice

A holiday house once stood on a sloping plot above the Berounka river inside the Křivoklátsko protected landscape area. It is gone, and our task was to document its replacement. For private clients we prepared the design documentation for the permit application, covering a modular timber building set on a masonry basement.

The brief was a new holiday house on a plot that falls towards the Berounka river and sits inside the Křivoklátsko protected landscape area. An older recreational building stood on the same plot and has been demolished, so in substance this is a new building replacing one that no longer exists. The clients are private individuals, which is why the client field reads as anonymised. The goal was the Czech DSP stage, the design documentation submitted with a combined planning and building permit application.

The work is grounded in site data. We laser scanned the plot and registered the scans into a single point cloud, and the coordinates of the foundation slab were available from a measured survey. Surveying and design sit in the same office here, so the point cloud fed straight into the model. Older material existed as well, a design by another practice from 2017 and a geotechnical investigation from 2018. Material of that age is input rather than a finished answer, because both the brief and the regulations move on in the meantime. A BIM model was then built in Revit, including the interior fit out with sanitary ware, furniture and openings, and the drawings were generated from that model. An IFC exchange model kept the structural engineer working on the same geometry as the architectural team.

The house has three levels. A club room with services in the basement, a living room with a kitchen area and a terrace on the ground floor, two bedrooms and a bathroom above. That adds up to roughly 135 m² of floor area and about 520 m³ of enclosed volume. The pitched roof rises at 35° and carries a standing seam metal covering, and heating is designed as an air to water heat pump with underfloor distribution. No new utility connections are created, the building ties into an existing well and an existing wastewater tank. The clients signed off the concept over a set of visualisations and floor plans before the drawing set was finalised. Detailed design for construction was outside the scope of this commission and the permit stage does not replace it. The model the set was generated from is the usual starting point for that next stage.

Project challenges

The hardest part is joining two different worlds. The upper part of the house is a catalogue timber module with fixed dimensions and fixed build ups. The basement is the opposite, individually designed masonry set into a slope. The two have to meet precisely and satisfy the fire and structural assessments at the same time, so they are resolved in parallel rather than one after the other. The site adds its own constraints. A sloping plot inside a protected landscape area drives the siting, the levels and the appearance of the building, and those are exactly the points an authority asks about. The third issue is language. When a new building replaces one that has been demolished, the vocabulary of new build and of reconstruction tends to get mixed in the documents. Factually it is a new building on the same plot, and every part of the documentation has to say so consistently.

Project outputs

• Accompanying report (part A) and summary technical report (part B)
• Technical report for the architectural and building design, part D.1.1.1
• Site plans C1 to C3, including the coordination site plan
• Floor plans, sections and elevations, parts D.1.1.2 to D.1.1.4
• Drawing and schedule of construction build ups, part D.1.1.5.1
• Fire safety design and structural design including the structural assessment
• IFC coordination model for the structural engineer
• Set of visualisations used for the client sign off of the concept
• BIM model in Revit (RVT) and the point cloud from laser scanning (RCS)