Ductwork shop drawings produced from the coordinated Revit model — DW/144 compliant, spool-numbered, and dimensioned for direct use in the fabrication shop. No manual redrawing step. No interpretation gap.
We cover the complete range of deliverables your project requires — modeled, coordinated, and documented to the standard your site team can actually build from.
Traditional ductwork shop drawings are produced by a draughtsman who takes the coordination agreement from a meeting, interprets it, and redraws it in CAD. The problem with that process is the interpretation step. Duct offsets agreed in a coordination meeting are sometimes recorded as sketch notes. Hanger positions discussed verbally don’t make it into the drawing. Transitions that were changed late in the coordination process appear in the drawing in their original position.
When shop drawings are produced from a coordinated Revit model, the interpretation step is removed. The duct offset in the drawing is the duct offset in the model — the one that was agreed in the coordination meeting, updated in the model at the time, and included in the signed construction release. The fabricator receives exactly what was coordinated.
For UK projects following BESA DW/144 and working within BS EN 1505 duct sizing standards, this also means the gauge and stiffening requirements can be generated automatically from the model data and incorporated into the drawing annotation — reducing the manual effort required to produce a complete fabrication package.
We confirm that the ductwork model has been through coordination sign-off and all clashes are resolved. We do not produce fabrication drawings from an uncoordinated duct model.
We work with the contractor to define spool boundaries — where one prefabricated section ends and the next begins — based on site access, installation sequence, and vehicle delivery constraints.
Coordinated duct plan views are extracted from the Revit model by floor and zone. Duct sizes, levels, offsets, and access door positions are annotated. Support spacings are added per the applicable standard.
Section cuts through congested areas — plant rooms, riser shafts, multi-service ceiling voids — are added where depth relationships cannot be read from plan views.
Individual spool sheets are produced for each numbered duct section, showing overall dimensions, connection geometry, and stiffening requirements for workshop fabrication.
A duct specification schedule is produced listing each section with material, gauge, stiffening class, and sealing class per DW/144 or SMACNA as applicable.
Completed drawings are reviewed against the Revit model. Dimensions are checked on critical offsets and transitions. Drawings are issued in PDF and DWG at the agreed revision.
Yes. For UK projects, BESA DW/144 is the default ductwork fabrication standard. Our duct shop drawings incorporate DW/144 gauge requirements, stiffening classifications, access door sizing, and sealing class requirements. For international projects, we work to SMACNA HVAC Duct Construction Standards or project-specific fabrication standards as specified in the MEP specification.
Yes. Spool-level fabrication drawings are a standard part of our duct shop drawing scope. We define spool boundaries in consultation with the contractor, assign spool reference numbers, and produce individual spool sheets showing all dimensions, connection geometry, and material specification required for workshop fabrication. The spool reference is incorporated into the installation drawing so site teams can identify and position each section.
Kitchen extract ductwork — commercial cooking extract, grease extract systems — is subject to DW/172 (BESA guide for commercial kitchen ventilation) in addition to DW/144. We model kitchen extract as a separate duct system with the required fire-rated construction, grease filters, and access provisions incorporated into the model and reflected in the shop drawings. For specialist systems including clean rooms, pressurisation, and laboratory exhaust, we apply the relevant project specification and applicable standards.
Yes. Where ductwork has been installed without full BIM coordination, or where post-installation as-built records are required, we can develop as-built duct drawings from site measurements or 3D laser scan data. Point cloud data is processed in Autodesk ReCap and used as the basis for a Revit as-built model, from which as-built drawings are extracted.
Design changes during construction that affect ductwork routing or sizing are managed through a formal revision process. We update the Revit model to reflect the change, rerun coordination checks on the affected zone, and issue revised shop drawings with a new revision. Spool drawings affected by the change are reissued, and the drawing register is updated. We document the reason for revision and the coordination impact in the revision note.
