Common mistakes on building drawings
![]() |
Many types of drawing can be used during the design and construction of buildings, often prepared by different disciplines or teams, working separately from one another. There are several common mistakes that can be made when producing or interpreting drawings that can lead to costly delays and avoidable remedial work.
A simple but common mistake is drawings not being complete. This can be a particular problem where designers do not have the necessary experience, supervision, quality systems or time to produce the drawings required. Incomplete drawings can lead to requests for information and change orders when the work starts on site.
Designers may also omit some detailing during the design process, such as window details or roof construction details, intending to complete them later, and will instead provide notes about what that portion of the construction should consist of. This can become a problem If they do not return to update the drawings before construction begins.
Drawings may not be coordinated, in particular if they are prepared by different teams, for example, the information on structural drawings may not be consistent with ductwork drawings. This can result in 'clashes', such as ventilation ducts running through structural beams (a hard clash), or insufficient space for installation works or access for maintenance (a soft clash). To try and void this problem, the design team should regularly review all up-to-date working drawings to ensure that they coordinate accurately.
Building information modelling (BIM) can help prevent clashes. Clash detection software can identify clashes between different disciplines' BIM data and generate clash reports. However, this should not be relied upon as a fail-safe check, and should not be used to justify poor design co-ordination processes. For more information see: Clash avoidance.
There may also be inconsistencies between drawn information and written information, such as schedules or specifications. It is important therefore that information is not duplicated between different types of document, but rather that one refers to the other. For example, a drawing may include notes referring to additional details in specification clauses.
In terms of personal drawing style, designers may have in-house habits that are not understood by other teams or disciplines. This can lead to misinterpretation and mistakes. It is important therefore that drawings adopt standard methods and procedures for preparation, symbols, hatching, annotation and so on. These should be agreed at the outset so that early drawings do not have to be corrected. This is particularly important when drawings are prepared using computer aided design (CAD) or BIM. BIM can involve the federation of information prepared by multiple teams to create a single model. If the information is not created consistently, incompatibilities can emerge that can be costly and time consuming to correct.
In terms of technical details, common mistakes include:
- Incorrect or inconsistent scales being used across drawings.
- Doors opening the wrong way or with insufficient opening space (i.e. opening into other doors, cabinets, windows, etc.).
- Facilities located in impractical places.
- Undersized, impractical or awkward spaces.
- Poorly detailed junctions or abutments between different components or systems.
- Incorrect symbols.
- Inconsistent revision numbers.
- Poor reproduction.
- File exchange or conversion errors.
- Software incompatibilities.
- Un-buildable, or difficult to build elements.
- Missing components.
- Inconsistent information.
- Illegible writing.
- The use of acronyms that are not understood.
- Notes that are not understood.
[edit] Related articles on Designing Buildings
- Common mistakes in construction tenders.
- Common spelling mistakes in the construction industry.
- Defects.
- How to draw a floor plan.
- Manual drafting techniques.
- Perspective.
- Rotring.
- Symbols on architectural drawings.
- Technical drawing.
- Techniques for drawing buildings.
- Types of drawings.
- Working drawing.
Featured articles and news
Ebenezer Howard: inventor of the garden city. book review.
Grenfell Tower fire – eight years on
A time to pause and reflect as Dubai tower block fire reported just before anniversary.
Airtightness Topic Guide BSRIA TG 27/2025
Explaining the basics of airtightness, what it is, why it's important, when it's required and how it's carried out.
Construction contract awards hit lowest point of 2025
Plummeting for second consecutive month, intensifying concerns for housing and infrastructure goals.
Understanding Mental Health in the Built Environment 2025
Examining the state of mental health in construction, shedding light on levels of stress, anxiety and depression.
The benefits of engaging with insulation manufacturers
When considering ground floor constructions.
Lighting Industry endorses Blueprint for Electrification
The Lighting Industry Association fully supports the ECA Blueprint as a timely, urgent call to action.
BSRIA Sentinel Clerk of Works Training Case Study
Strengthening expertise to enhance service delivery with integrated cutting-edge industry knowledge.
Impact report from the Supply Chain Sustainability School
Free sustainability skills, training and support delivered to thousands of UK companies to help cut carbon.
The Building Safety Forum at the Installershow 2025
With speakers confirmed for 24 June as part of Building Safety Week.
The UK’s largest air pollution campaign.
Future Homes Standard, now includes solar, but what else?
Will the new standard, due to in the Autumn, go far enough in terms of performance ?
BSRIA Briefing: Cleaner Air, Better tomorrow
A look back at issues relating to inside and outside air quality, discussed during the BSRIA briefing in 2023.
Restoring Abbotsford's hothouse
Bringing the writer Walter Scott's garden to life.
Reflections on the spending review with CIAT.
Retired firefighter cycles world to raise Grenfell funds
Leaving on 14 June 2025 Stephen will raise money for youth and schools through the Grenfell Foundation.
Key points for construction at a glance with industry reactions.