Metal Frames and Podiums for HVAC and Chillers

Why separate frames and podiums for HVAC and chillers on the roof are needed

Industrial chillers, rooftop air conditioners, and ventilation units are rarely installed “just on the slab.” They require metal frames, brackets, and podiums that:

• redistribute the load onto the roof’s load-bearing structures;
• provide the required installation elevation and slopes;
• create space for piping, drainage, and maintenance;
• reduce vibration and noise transmitted into the building.

For HVAC designers, installation companies, and owners of retail and warehouse facilities in Tashkent, the question is not whether to make a frame, but how to avoid mistakes when the frame and equipment are already on the roof, but the roof cannot handle the load or the dimensions don’t match.

What metal structures are used: frames, brackets, podiums

Support frames for HVAC and chillers

Most often these are welded or bolted metal structures made of steel sections:

• a closed rectangular contour matching the equipment footprint;
• longitudinal and transverse beams under the support points;
• connection nodes to embedded parts, beams, or decking.

Frames are used for chillers, rooftop units, and large air handling units.

Brackets and cantilever systems

Brackets are used when equipment is cantilevered beyond the roof edge or attached to walls/beams:

• cantilevers for medium-sized air conditioning units;
• brackets for air ducts and silencers;
• supports for outdoor units of VRF systems.

Here, the calculation of cantilever length and deflection, joint stiffness, and weld quality are critical.

Podiums and service platforms

Podiums are frames raised on posts above the roof:

• to level the installation elevation on complex roof geometries;
• to bypass parapets, skylights, trays;
• to provide safe access for equipment maintenance.

Often a podium combines the functions of a support frame and a service platform with stairs and guardrails.

Key requirements for frames for specific equipment

To ensure the frame “fits” the equipment without rework on the roof, you must consider at the calculation stage:

• Overall dimensions and support points of the specific chiller or unit model;
• weight (operating, with refrigerant and water);
• dynamic loads from compressors and fans;
• mounting scheme: via vibration isolators, rails, OEM frames;
• operating conditions: exposed roof, sun, dust, possible chemical exposure;
• roof type: flat/pitched, solid slab, profiled sheet on beams, presence of embedded parts.

Without this input, the calculation becomes guesswork and installation turns into on-site rework.

7 common mistakes at the specification and design stage

1. No reference to a specific equipment model

A common situation: the specification only says “frame for 200 kW chiller.” The actual model is selected later, and it turns out that:

• support points do not align with the frame beams;
• the chiller length/width exceeds the frame;
• bolt holes do not match the plates.

As a result, on the roof they cut, extend, and drill what has already been painted and delivered.

How to avoid it: specify the model and manufacturer in the specification from the start and attach a drawing/catalog with support points.

2. Ignoring the roof structure

The client provides only an equipment layout plan. Without information on the roof structure, the metalwork manufacturer cannot see:

• where beams and girders run;
• which areas are load-bearing and which are only insulation and screed;
• where supports can and cannot be placed.

The frame may end up bearing on “weak” zones, and the load goes into the insulation and waterproofing.

How to avoid it: attach a fragment of the structural section to the specification: roof layers, beam layout, allowable loads.

3. No connection details to the building

The wording “free-standing frame on the roof” without wind and seismic calculations for Tashkent conditions is a risk of:

• equipment shifting in strong winds;
• roof damage from a “walking” frame;
• issues during inspections by operating organizations.

How to avoid it: define the connection scheme in advance: to embedded parts, beams, parapets; describe it in the specification and coordinate with the building structural engineer.

4. Incorrect handling of vibration isolation

Sometimes vibration isolators are simply “placed by eye” on the top frame members. Typical consequences:

• uneven load distribution across isolators;
• increased vibration and noise in rooms;
• accelerated wear of vibration isolators.

How to avoid it:

• use the vibration isolator layout provided by the equipment manufacturer;
• provide a corresponding beam or reinforcement plate under each isolator;
• account for the isolator height when calculating elevations.

5. Underestimating corrosion resistance

Tashkent combines sun, dust, and temperature fluctuations. If the frame is made of plain carbon steel without proper protection, after a few seasons:

• corrosion spots appear in weld and cut areas;
• contact with fasteners and vibration isolators deteriorates;
• stiffness of individual elements decreases.

How to avoid it:

• specify the coating type in the specification (for example, powder coating on prepared metal) or another protection option;
• agree on coating thickness and color if the frame is visible from the façade or neighboring buildings.

6. Overly generic or outdated drawing

Sometimes a “typical frame” drawing is sent as the specification, which has already been modified several times on different sites. It:

• lacks current dimensions for the new chiller model;
• does not account for roof changes;
• does not reflect actual installation clearances.

How to avoid it:

• update the drawing for the specific project before ordering;
• if there is no design documentation, describe the requirements and order structural design and calculation.

7. Unaccounted time for approvals and revisions

Even if the frame is correctly calculated, timelines can slip due to:

• late submission of the final specification;
• additional approvals with the building structural engineer;
• last-minute changes to the equipment model.

How to avoid it:

• allow time for structural calculation and approval before starting production;
• fix a “point of no return” after which changes to the specification affect lead time and cost.

Mistakes in choosing materials and manufacturing technologies

Material: what is important to specify

Frames, brackets, and podiums for HVAC and chillers are usually made from:

• carbon steel (hot-rolled and cold-formed sections) with protective coating;
• stainless steel — locally, where there is constant contact with moisture or aggressive media.

Typical mistakes:

• requiring “everything in stainless steel” without real need — unjustified cost increase;
• no indication of steel grade and protection — the manufacturer chooses the minimum option, which may not meet service life requirements.

Technologies: laser cutting, bending, welding, painting

When ordering through contract manufacturing, it is important to understand which operations will be involved:

• laser cutting — precise geometry of plates, gussets, flanges;
• metal bending — fabrication of stiffeners, brackets, complex-shaped elements;
• welding — assembly of frames, posts, support nodes;
• powder coating — final protection and appearance.

Mistakes arise when the specification lacks information on:

• which surfaces must be painted and which must not (for example, areas to be welded on site);
• whether there are temperature limits for the curing oven (for assemblies with pre-installed components);
• which geometric tolerances are critical for equipment mounting interfaces.

What affects the cost of frames and podiums: factor table

The cost of metal structures for HVAC and chillers on roofs in Tashkent cannot be named in advance without a specification. Below are the main factors that affect the final estimate.

The more detailed the input data, the more accurately and quickly a quote can be provided without a “margin for the unknown.”

Timelines: from draft specification to roof installation

Timelines depend on complexity and production workload, but the sequence of stages is typical:

1. Collecting input data and draft specification
   Providing information on equipment, roof, coating, and installation requirements.

2. Preliminary calculation and structural concept selection
   Assessing section sizes, support scheme, steel quantity.

3. Design documentation development (if needed)
   Drawings of frames, brackets, podiums, connection nodes, parts list.

4. Approval
   Clarifying dimensions, elevations, nodes with the HVAC designer and building structural engineer.

5. Release to contract manufacturing
   Laser cutting, metal bending, welding, grinding, geometry control.

6. Painting and shipment preparation
   Powder coating (if provided), packing, element marking.

7. Delivery and roof installation
   Lifting to the roof, assembly, installation of vibration isolators and equipment.

To avoid disrupting the overall HVAC commissioning schedule, it is important to start work on frames and podiums before the final selection of finishes and secondary disciplines — immediately after the engineering and equipment scheme is fixed.

How to properly prepare a specification for calculation and fabrication

For calculation and fabrication of metal frames, brackets, and podiums for HVAC and chillers on roofs in Tashkent, it is advisable to specify in the brief:

1. Equipment data

   • make and model of the chiller/unit;
   • overall dimensions and (operating) weight;
   • support point and mounting scheme (drawing or catalog excerpt);
   • presence and layout of vibration isolators.

2. Roof and building data

   • roof type (flat/pitched), layer structure;
   • layout of load-bearing beams, girders, embedded parts;
   • allowable loads on the roof in the installation area.

3. Structural requirements

   • type: frame, podium, brackets, service platforms;
   • required installation elevations relative to the roof;
   • need for height adjustment, presence of guardrails and stairs.

4. Materials and coating

   • base material (steel, stainless — where exactly);
   • type of protective coating (for example, powder coating);
   • requirements for color and appearance.

5. Installation and logistics

   • site address in Tashkent or region;
   • lifting size limitations for roof access;
   • delivery format (welded assemblies or knock-down bolted units).

The more accurate the specification, the lower the risk of errors and on-site rework.

BRIX.UZ contract manufacturing capabilities for HVAC projects

BRIX.UZ operates as a contract manufacturer of metal structures for industrial and commercial facilities in Tashkent and across Uzbekistan. For frames, brackets, and podiums for HVAC and chillers we use:

• laser cutting of sheet metal for precise plates, gussets, flanges;
• metal bending for stiffeners, brackets, complex-shaped elements;
• welding of frame carcasses, posts, support nodes;
• powder coating for corrosion protection and neat appearance.

We work to the client’s specification: from calculation for specific equipment to fabrication of a batch of metal structures, taking into account deadlines and roof installation requirements.

Common client mistakes: short list

1. Ordering a frame “by eye” without reference to a chiller or unit model.
2. No data on roof structure and allowable loads.
3. Ignoring vibration isolation and actual vibration isolator layout.
4. Unaccounted access routes for maintenance, drainage, and piping.
5. Demanding maximum savings on steel and coating without assessing service life.
6. Sending outdated or incomplete drawings to production.
7. Trying to “catch up on schedule” by cutting time for calculation and approvals.

FAQ: frequently asked questions

1. Is it possible to make one “universal” frame for different chillers?
In theory you can allow for extra space and load capacity, but this is almost always more expensive and more complex than a frame for a specific model. It also worsens roof layout.

2. What if the equipment model has not yet been selected but deadlines are tight?
You can preliminarily define support locations and a general podium scheme, but it is better to start production after the model is fixed and its dimensional drawing is obtained.

3. Can you calculate a frame if we have no drawings, only a catalog sheet?
Yes, calculation is possible based on catalog data and the support point scheme. It is important that the catalog specifies dimensions, weight, and mounting scheme.

4. How to account for seismic and wind loads for roof frames in Tashkent?
When designing the structure, loads specified in the building project are considered. At the specification stage, it is important to provide the design load requirements from the structural engineer.

5. Can stainless and regular steel be combined in one structure?
Yes, stainless steel is often used locally — in areas of constant moisture or aggressive media, while the main frame is made of carbon steel with protective coating.

6. What if part of the roof and embedded parts are already installed and the equipment scheme has changed?
In this case, an up-to-date site survey and revised layout are required. Based on them, the frame and podium design can be reworked to use existing embedded parts and avoid opening the roof.

7. Can a frame be placed directly on a soft roof without anchoring?
Without calculation and verification of allowable loads, this is a risk for waterproofing and safety. Typically, load-distribution plates, supports with roof membrane protection, or anchoring to structural elements are used.

8. Do you only fabricate, or can you help with calculation as well?
We can work both from finished drawings and from a specification, with structural calculation for specific equipment and roof conditions.

How to request a metal structure calculation for your equipment

To obtain a calculation for metal frames, brackets, and podiums for HVAC and chillers on the roof, prepare and send:

• make and model of the equipment (chiller, rooftop unit, air handling unit);
• overall dimensions and weight of each unit;
• support point and mounting scheme (drawing or catalog);
• a fragment of the roof plan showing the installation location;
• information on roof structure and allowable loads;
• requirements for structure type (frame, podium, brackets, service platforms);
• preferences for material and protective coating;
• site address and installation/logistics constraints.

After receiving this data, we can perform the calculation, propose a structural solution, and provide fabrication lead times.

Request a calculation

Send your specification in any convenient format (drawings, PDF, plan sketch) and receive a technically sound solution for metal structures for your HVAC equipment, taking into account roof conditions and construction schedule.