OFFLINE · PRACTICAL RETURN OPTIONS V27.37
Field walkthrough → automatic assessment

Assess the building. Plan the supplies.

Field-tested sizing calculations, supply recommendations, and report previews in our new black-and-green interface.

Job & sizing

Cavity returns are recorded as existing conditions only; they are not assigned a verified airflow capacity. Check local code and manufacturer requirements before recommending reuse.

Measure the grille face, not the duct opening. Estimates use gross grille area; actual free area and delivered CFM must be verified.

Add as many returns as needed. Each receives its own preliminary recommended duct size.

Residential ceiling-height choices retain your original 0.8 / 0.9 / 1.0 CFM/ft² factors. Commercial occupancy uses editable preliminary airflow factors. Existing permitted outdoor-air ventilation is retained; LAS FieldMech does not recalculate ventilation requirements.

Add a room

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Enter a room name and square footage. The gray examples are hints, not filled-in answers.

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Commercial occupancy factors are preliminary field estimates, not engineered loads. Existing outdoor-air ventilation is outside LAS FieldMech replacement sizing scope. Draft planning aid. Branch capacities are provisional and require verification of installed airflow, available static pressure, duct length/fittings, noise and register performance. Damper percentages are starting positions, not calculated flow reductions.