Overall HVAC System Strategy

Designing an HVAC system on Revit was definitely a challenge for me. Despite the struggles I encountered, I will admit that I certainly enjoyed the process and have learnt more than I could have ever imagined within a week.

My overall HVAC system design revolves around ensuring all spaces are adequately ventilated and energy efficiency is at the forefront of my design. Considering this is an academic building, I believe it is important to increase natural ventilation and so, I implemented an open study area within the center of the building.

The building is 30,000 sq. ft. and code requires 20 cfm per person, which is approximately equivalent to about 150 sq. ft. per person — this results in an occupancy capacity of 30,000 sq.ft./150 sq.ft. per person = 200 people occupancy capacity for my building.

Cooling and Heating Strategies

Passive cooling is my priority and I installed architectural and mechanical features to enhance the conservation of energy, such as: self-operable windows, an exposed atrium with optimized ventilation, glazing on windows, and economizer mode controls within the BAS. When passive cooling is not a feasible option, there are 2 vertical split systems installed that feed both floors — each floor contains their own AHU split system for greater temperature control. The split systems supply heating and cooling for the entire building other than the atrium, which is an exposed outdoor area. The supply diffusers installed provide 500 cfm of air and the quantity of diffusers and returns are determined by the area.

3D View

Angled 3D View

North Elevation View

Close View of Duct Layout Design

Level 1: HVAC Layout

Level 2: HVAC Layout

View of HVAC System Installed within Architectural Model

First Floor:

Second Floor:

HVAC Equipment Selected

Return Diffusers

Supply Diffusers

Air Handling Unit

Mechanical Flow Calculations

Space Type Energy Analysis

Room Schedule

Room Floor Plan

Space Schedule

Special HVAC Challenges

The greatest challenge I encountered when designing my HVAC system was ensuring my ducts aligned with my ceiling heights. Every time I created my floor layout for my ductwork, it would be misaligned and the amount of time it took to ensure all of my supply diffusers and return grills were aligned was stressful. I did not anticipate having this problem when I completed my HVAC model via the mechanical template since my elevations were aligned, but the problem arose when I linked my mechanical model to my architectural file. Once I linked them, my elevations were all over the place and it took quite a bit of time to recalibrate everything since many of my design elements readjusted when I copied my floor levels to align my designs. In addition, I spent hours attempting to figure out why I was unable to get the systems analysis report to work for me. I sought out help from youtube, revit’s help pages, even friends and I do not know why it would not work despite all of the troubleshooting I performed.