Rooftop addition · calculationFrom €629 excl. VAT (business) · €761.09 incl. VAT (private customers)What can be included in your commission?
Your quote specifies the exact elements and documents. The following topics matter for this structural calculation:
The additional storey
The load-carrying elements and loads of the agreed rooftop addition.
The existing load path
The structural elements below the addition that need to be considered within the agreed assessment.
Connections and drawings
The agreed connection details and drawings to coordinate the new and existing construction.
Calculations, drawings and construction work are separate parts of a project. Your quote defines what is included. Mention any questions about a site visit, temporary support or design changes.
Start with a short description and the information you already have. Sending an enquiry is free of obligation and does not place a paid order.
What is assessed?
An extra layer adds weight and wind load. That is why the structural engineer looks beyond the roof: the entire bearing route to the foundation is relevant. A light build-up can have advantages, but still needs to be calculated.
Existing drawings do not always reflect the actual situation. A site survey or additional investigation may be necessary before the design is determined.
What data is needed?
The following information can be used to prepare the assessment. The structural engineer determines whether additional research is necessary.
| Information | What should you send? |
|---|---|
| Existing construction and foundation drawings | Gather available records for the whole house, including earlier alterations. |
| Preliminary design of the additional storey | Mark the additional storey and proposed stair opening on the design. |
| Desired facade and roof materials | Include available product specifications and identify choices that are still open. |
| Photos and available research reports | Identify the storey shown in each photo and the building element covered by each report. |
Not everything available yet? Describe what you have and what is missing. You do not need to calculate load capacity yourself. Any survey or additional investigation needed will be discussed for your project.
Materials and drawings
The choice of materials and connections follow from the design. Read more about Structural timber and the difference between a architectural drawing and a construction drawing.
How does the process proceed?
You describe your project and share the available data. The assignment, any additional information and planning are then coordinated. Check it out complete step-by-step plan for all phases.
Price and scope: agree these points first
The price above is a starting point. Compare quotations covering the same elements and ask for additional work to be listed separately.
What should be calculated?
Define both the new storey and the existing load path to be assessed. Discuss the stair opening, connections and any strengthening of the house and foundations.
What needs a separate agreement?
A site survey, material testing, ground investigation, architectural drawings and permit assistance are not automatically included. Ask which supplier documents will be checked.
What affects the schedule?
Assessing the existing building comes before final choices. Different materials, a changed layout or missing archive records can affect the investigation and schedule.
Ask your quotation to identify who prepares the calculations, who provides the drawings and who answers technical questions. State your preferred date; feasibility is agreed for your commission.
Can I already order material?
Order structural parts based on the coordinated and current design data. A preliminary estimate is not a complete basis for this.
Is a site visit necessary?
That depends on the project and the available information. Sometimes drawings and photos are sufficient for the inventory; sometimes an admission or additional examination is necessary.
What happens if my plan changes?
Report changes before they are implemented. The structural engineer assesses whether calculations and drawings need to be adjusted.
Frequently asked questions about roof construction
Is a light roof structure always possible?
A low net weight can be beneficial, but is not an automatic confirmation. Use load, wind, connections, stability and the existing carrying route are also relevant. The structural engineer must determine what information about the home and foundation is required to assess the design.
Which drawings are needed for a roof structure?
Collect the new design and available drawings of the existing foundation, floors, load-bearing walls and roof. Add information about previous breakthroughs and renovations. Indicate which data is missing. The structural engineer then determines whether a site survey or further investigation is necessary.
Should the new stairs also be included?
A new stair opening can change the floor and surrounding structure. Therefore, share the stair location, desired opening and floor heights at the same time as the design of the structure. Determine who calculates the opening and who coordinates the dimensions with the stair supplier.
What if the existing home needs to be reinforced?
Ask which reinforcements are being developed within the assignment and what additional information is required for this. Discuss the consequences for layout, finishing, implementation and budget. Include the chosen solution in the current drawings before ordering the structure or required parts.
Related structural topics
- Roofs and roof extensions
- Foundations and earth retaining structures
- Complete buildings and transformations
Your project location
Provide the building address and share available drawings and photographs. Discuss whether a site survey is needed and which travel or investigation costs form part of the commission.