Can I enquire without original drawings?

Yes. Send photos, a sketch and a description of your plans. We identify the missing information. Archive research, a site survey or further investigation may be needed and will be agreed separately.

What does the approval guarantee cover?

If the municipality requests additional information about our calculations within the original brief, we provide it within the agreed scope at no additional professional fee. This does not guarantee a permit. Read the terms on the guarantee page.

How soon will the documents be ready?

The schedule is confirmed in the quotation after your information has been assessed. The completeness of the drawings, further investigations and the scope of calculations determine the turnaround time. Include your preferred date in your enquiry.

Structural calculations for an additional storey

What does this project require structurally?

Additional weight passes through floors, walls and columns to the foundations. Wind loads, stability and the connection to the existing house also change. Calculating only the new roof is therefore often insufficient.

Which information helps with your enquiry?

Drawings of all storeys
Design of the new storey
Information about existing foundations and floors
Material build-up and any previous calculations

You do not need to have everything ready. State which documents are available and what is still unknown. We first assess whether there is enough information to define the brief. A site survey or further investigation may be necessary.

What can your brief include?

Analysis of the agreed load path
Design of new load-bearing elements
Design justification for the existing elements being assessed

The quotation records which elements will be calculated and drawn, the information used as a starting point and when the documents will be delivered. This makes the scope clear to you, your adviser and your contractor.

What is not automatically included?

Architectural drawings, ground investigations, archive research, site visits, supplier calculations, temporary support and construction supervision are included only when explicitly agreed. Materials and construction work are outside the calculation fee.

Permits and structural assessment

Check the procedure for your activity and location through the Dutch Omgevingsloket. A structural report substantiates the agreed elements; it does not determine whether the entire building proposal is permitted.

Read about permits and the municipality's role

From information to final project documents

Once your enquiry is agreed, the design basis is recorded, calculations and drawings are prepared and internally checked. Your contractor receives the final documents with a revision reference. Any discrepancy in the existing situation or change to your plans must be reported before work on the affected element continues.

View the process