Drawing a floor plan without SketchUp: from sketch to VEKA volumes

For every EPC file, you calculate from three key figures that follow directly from your floor plan:

• Gross floor area: the area of each level, measured to the outside of the exterior walls, added up across all levels within the protected volume.
• Protected volume: the volume of all spaces that are heated or intended to be, from basement to attic, bounded by the heat-loss surfaces.
• Heat-loss surfaces: every surface through which the protected volume loses heat, such as an exterior wall, a roof plane, a slab-on-grade floor, or a wall facing an unheated garage or storage room.

You don't determine these three figures independently: they all follow from the same floor plan, with the right levels, walls and openings drawn correctly. A mistake in your floor plan, such as a wrongly delimited garage, therefore carries through into all three figures.

The classic workflow has two steps: first you measure on site with a tape measure or laser and note everything on paper or in a sketch app, then you redraw those measurements that evening or the next day in SketchUp. That handover already costs time on its own, but the real problem is that mistakes only become visible while redrawing: a forgotten wall, a swapped measurement, a corner that didn't quite feel square on site. By then you're no longer there to re-measure it.

A second time sink is that SketchUp has no idea what VEKA needs: you have to manually calculate or export areas and volumes yourself, per level, and transfer them separately into the VEKA portal. A floor plan drawn directly on site, with the right levels and a tool that calculates volumes automatically, eliminates both steps.

The wall-by-wall tool in Plattegrond v2 lets you draw each wall by entering a starting point, a direction and a length, while you literally walk through the building. For the length you have two options:

• Bluetooth laser: connect a laser (Leica DISTO range or common Bluetooth lasers from brands including Bosch, Stanley and Stabila) and every measured distance lands directly in the right field, with no retyping.
• Manual entry: without a laser on hand, measure with a tape measure and type the length in yourself.

Either way, the file shows afterwards which measurement came from the laser and which was entered manually, so if in doubt you immediately know which value to check first.

Few homes have perfectly square corners, and on site you rarely measure to the millimetre. Plattegrond v2 handles that in two ways.

Automatic straightening

A corner within 45 degrees of the nearest right angle is automatically straightened to that 90° multiple. A wall you draw slightly off-square therefore still ends up straight on screen, in line with how most homes are actually built.

Rescaling on an extra measurement

If you re-measure a wall you'd already drawn, the app only adjusts the sides not yet measured: a side you've already measured with the laser keeps its exact length. Sides you haven't measured yet automatically inherit the correct scale from the axis you have measured, so your floor plan immediately shows realistic proportions, even before you've measured everything.

For aligning corners and edges, a 400 mm snap tolerance also applies: draw a new wall close to an existing corner or edge and the drawing snaps to it automatically.

Plattegrond v2 works with a fixed order of levels: basement (K), ground floor (GL), upper floors (V1 to V3) and attic (Z). Which levels your file expects is derived automatically from the data you entered when creating the file: the number of levels, and whether a basement or attic is present.

You draw each level separately, with its own outer outline, interior walls and ceiling height. That matters because the gross floor area per level gets added up, and a floor with a smaller footprint (for instance because of a sloped roof or a set-back facade) should never simply inherit the area of the level below it.

The most common mistakes when drawing a floor plan are:

• Not correctly delimiting an extension or garage as unprotected volume, which throws off the heat-loss surface calculation.
• Skipping or merging a level, for instance a mezzanine or a partially lowered ceiling, resulting in an incorrect gross floor area.
• Drawing only the outer outline without interior walls, which stops rooms from being correctly delimited for the rest of the file.
• Manually overwriting an already-measured side during a correction, instead of letting automatic rescaling do the work on the unmeasured sides.
• Setting the front facade orientation incorrectly, which affects the sun exposure and heat-loss calculation per facade.

Each of these mistakes is usually invisible on screen: you only notice once the calculated areas or volumes don't match what you saw on site.

If you have an existing building plan from the architect as a PDF, you no longer need to start from scratch. The floor plan from an architect's PDF (beta) feature recognises walls, doors and windows in the uploaded plan and prepares a first floor plan per level.

That pre-drawn plan is a starting point, not a final result: you check it during the survey, correct where recognition goes wrong, and still measure the critical dimensions with the laser or tape measure to be sure the plan matches the as-built situation. An architect's plan shows the design after all, not necessarily what was ultimately built. Because the feature is in beta, this on-site check remains a fixed part of your workflow.

Once your floor plan, levels and openings are drawn, the app automatically calculates:

• The gross floor area per level and the total.
• The protected volume, based on the ceiling heights per level.
• The heat-loss surfaces per facade, roof plane and floor, with the correct orientation per facade.

Those three figures form the basis of a large part of the VEKA data entry. You see them in your file, can check them against your drawing, and overwrite them manually where needed, for instance when a local peculiarity can't be correctly derived from the floor plan. That way you save the calculation work without losing control.