What should be prepared before drawing design begins?

What should be prepared before drawing design begins?

This question is very much to the point and directly addresses the core work of the MEP Director at the project initiation stage. Drawing design is not about drawing as soon as you start; it is about "troops and horses not yet moving, but provisions and fodder going first." As the MEP Director, before drawing design begins, I must ensure that preparations across the following six dimensions are fully in place; otherwise, subsequent design will inevitably require rework, clash, and exceed the budget.

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1. Confirmation of Brand Standards and Design Brief

This is the "constitution" of all design.

• Standard Reference: Whether it is Marriott, Hilton, InterContinental, or IHG, each brand has its own dedicated MEP Design Criteria (such as Marriott's MEP Design Criteria and InterContinental's Engineering Standards). These standards are usually more stringent than national standards. For example, Marriott requires guest room fresh air volume of no less than 30 CFM/room (about 50 m³/h), while GB 50736 only requires 30 m³/h·person; InterContinental requires the emergency generator to carry 100% of the hotel's fire load + 50% of life safety load + 25% of domestic load.
• Practical Key Points: The latest version (2024/2025 version) of the brand's MEP design guide must be obtained, and a "standards alignment meeting" must be held with the brand's engineering director. For example, Hilton has explicit requirements for the temperature and humidity control accuracy of the pool dehumidification system (26±1℃, RH 50-60%), while the national standard only gives a range. If this is not confirmed in advance, the brand review will directly reject it after design completion.
• Decision: If brand standards conflict with local codes (for example, Shanghai local standards require hotels to adopt solar hot water systems, but InterContinental standards do not allow rooftop solar to affect the facade), the MEP Director must lead the coordination with the brand, the design institute, and the drawing review center, and issue a Technical Deviation Application to clarify the solution and cost impact.

2. Full-Discipline Interface Division and MEP Point Load Information List

This is the insurance against "drawing clashes."

• Standard Reference: GB/T 50328 Code for Archiving of Construction Project Documents requires that a List of Interdisciplinary Information Submissions should exist before design. But more critically, the MEP Director must personally review the following information submissions:
• Architectural Discipline: Floor height, clear height requirements (for example, a five-star hotel lobby clear height ≥8 m, guest room clear height ≥2.8 m), shaft locations, equipment room dimensions (the minimum areas of the substation, boiler room, and chiller plant must be calculated in advance).
• Structural Discipline: Equipment foundation loads (for example, the chiller foundation load must be ≥8 kN/m²), reserved openings (such as the size and location of openings for air ducts passing through beams).
• Interior Finish Discipline: Ceiling shapes, light trough locations, curtain box depth, wall finish materials (affecting the depth and embedding method of switch and socket back boxes). For example, stone walls require embedded galvanized steel plates, while wood veneer can be slotted directly.
• Landscape Discipline: Outdoor lighting, irrigation water intake points, rainwater collection tank locations.
• Practical Key Points: Formulate an MEP Point Load Information Submission Schedule, requiring all disciplines to provide preliminary information submissions at the schematic design stage (rather than the construction drawing stage). For example, the interior finish discipline must provide the MEP point layout drawing for "guest room bedside table/desk/TV wall" in advance; otherwise, if the interior finish is adjusted by 1 cm later, the MEP pipelines will need to be rearranged.
• Decision: When the interior finish requirement for a "no main light design" causes extreme congestion of pipelines in the ceiling, the MEP Director must make the call: whether to use BIM simulation for pipeline coordination? Whether to move some pipelines into walls or under the floor? Whether the cost increase is within budget?

3. Investigation of Municipal Conditions and Local Policies and Regulations

This is the key to determining whether the system scheme can be implemented.

• Standard Reference:
• Power Supply: GB 50052 Code for Design of Power Supply and Distribution Systems requires hotels to clarify the municipal power supply level (Grade I loads require dual power supplies, and five-star hotels also require standby generators). The power supply bureau's Power Supply Scheme Approval must be obtained in advance to confirm: whether dual-circuit 10 kV lines on the same pole are allowed? Whether a self-built switching station is required?
• Water Supply: GB 50015 Code for Design of Building Water Supply and Drainage requires hotels to clarify the municipal water supply pressure (usually ≥0.25 MPa); if the pressure is insufficient, variable-frequency water supply equipment must be installed. A Certificate of Pressure at the Municipal Water Supply Connection Point must be obtained in advance.
• Gas: It is necessary to confirm whether the municipal gas pipeline has been laid to the red line boundary and the location of the gas pressure regulating station (it cannot be located in a densely populated area and must meet the GB 50016 fire separation distance of ≥6 m).
• Drainage: It is necessary to confirm the elevation of the municipal rainwater and sewage pipe network. If the hotel basement elevation is lower than the municipal pipe network, a sewage lifting pump station must be installed (according to GB 50014 drainage planning).
• Local Policies: For example, Beijing requires new hotels to achieve Green Building Level 2 or above, Shanghai requires hotel hot water systems to adopt a combined solar + air-source heat pump system (according to Hu Jian Guan [2015] No. 934), and Shenzhen requires hotels to reserve charging pile parking spaces ≥20% (according to Shen Fa Gai [2024] No. XX). If these are not investigated in advance, the construction drawing review will inevitably be rejected.
• Decision: If municipal gas is not available, an alternative scheme of "electric boiler + heat pump" must be launched immediately, and the impact on operating costs must be evaluated (the operating cost of electric boilers is 2-3 times that of gas), while an Energy Scheme Comparison Report must be submitted to the owner.

4. Full-Discipline Pipeline Coordination Principles and Clear Height Control Strategy

This is the MEP Director's most core coordination work.

• Standard Reference: GB 50222 Code for Fire Protection of Building Interior Decoration Design requires the clear height of evacuation corridors to be ≥2.2 m, but the clear height of five-star hotel lobbies and ballrooms is usually required to be ≥4.5 m. MEP pipelines (air ducts, cable trays, water pipes, sprinkler pipes) must be precisely positioned.
• Practical Key Points: Before design begins, a Pipeline Coordination Design Guideline must be formulated to clarify:
• Avoidance Principles: Small pipes yield to large pipes (air ducts > cable trays > water pipes > sprinkler pipes), pressurized pipes yield to gravity pipes (drainage pipes have priority), branches yield to mains.
• Clear Height Calculation: For example, standard guest room corridor: interior finish ceiling elevation 2.4 m, requiring reservation of: structural beam depth 0.8 m + air duct 0.3 m + cable tray 0.15 m + sprinkler main pipe 0.1 m + ceiling keel 0.1 m = 1.45 m; therefore, the clear height from the bottom of the structural beam to the floor must be ≥3.85 m.
• BIM Application: Decide whether to invest in BIM forward design (cost increase of about 15 yuan/m²). If the project is complex (such as a high-ceiling lobby or curved corridor), BIM must be used; otherwise, the later demolition and modification cost will be more than 10 times the BIM cost.
• Decision: When the interior finish requires a "no ceiling" design but MEP pipelines cannot be concealed, the MEP Director must decide: whether to adopt a "exposed ceiling painting + conduit routing" scheme? Or locally lower the slab to create "false beams"? This must be confirmed by signature of the MEP Director, Interior Finish Director, and architect.

5. Fire Protection System Scheme and Submission Review Prejudgment

This is a red line—there is no room for any wishful thinking.

• Standard Reference: GB 50016"Code for Fire Protection Design of Buildings"explicitly requires:
• Hotels are classified as "Class I high-rise public buildings" (hotels with building height >50m or area >1000m²) and must be equipped with a Fire Alarm System (FAS), automatic sprinkler system (sprinklers), and smoke control and exhaust systems.
• Guest rooms must be equipped with independent smoke detectors (per GB 50116 Clause 6.2.1).
• Kitchens must be equipped with gas leak alarms + automatic shut-off valves (per GB 50028).
• Practical Key Points: Before design begins, a "Fire Protection Scheme Pre-review Meeting" must be held with the local fire protection drawing review center (e.g., Beijing Fire Protection Review Center, Shanghai Drawing Review Center) to clarify:
• Whether "natural smoke exhaust" is permitted? If not, a mechanical smoke exhaust machine room must be provided (occupying area).
• Whether the fire water tank capacity must be calculated as the "sum of indoor and outdoor fire water demand"? Or can the outdoor municipal makeup water volume be deducted?
• Whether the sprinkler system must use "quick-response sprinklers" (typically required for five-star hotel guest rooms, per GB 50084 Clause 6.1.2).
• Decision: If the local fire department requires "hotel guest rooms must be equipped with fire hose reels" (per GB 50016 Clause 8.2.4, but not mandatory), the MEP Director must weigh: adding hose reels will result in exposed water pipes in guest rooms affecting the interior finish; should fire hydrants be added in corridors instead? This must be jointly determined with the Interior Finish Director and fire protection consultant.

6. Cost Budget and Bidding Strategy

This is what the owner cares about most.

• Standard Reference: GB 50500《Code of Bills of Quantities and Valuation for Construction Works》requires design estimate error ≤10%, but the MEP Director must lock in the "bulk equipment procurement strategy" in advance.
• Practical Key Points: Before design begins, the following must be completed:
• Equipment Selection List: For example, should chillers be centrifugal or screw type? Should brands be locked to "imported first-tier" or "domestic joint venture"? This directly affects the system scheme (centrifugal chillers require cooling towers; screw chillers can be air-cooled).
• Bidding Model: Should the "MEP general contract + owner-supplied equipment" model be adopted? For example, elevators, generators, boilers and other large equipment are often owner-supplied (to control brand quality), but embedded parts must be reserved in advance (e.g., elevator guide rail embedments, generator exhaust pipe embedments).
• Quota Design: Issue"MEP Cost Control Indicators"to the design institute, e.g., HVAC system cost ≤400 RMB/m², electrical system ≤300 RMB/m². If the design exceeds this, optimization must be carried out immediately (e.g., changing fan coil + fresh air system to VRV + fresh air can reduce cost by 20%).
• Decision: If the owner's budget is tight, the MEP Director must decide: should the "smart guest room control system" be downgraded to "ordinary switch panels"? Should the "BA system" be changed from full coverage to "monitoring key equipment only"? A"Cost Optimization Scheme Comparison"must be issued, clearly stating the impact on operations.

Summary: MEP Director's "Pre-design Checklist"

| No. | Preparation Item | Key Action | Standard/Code Reference | Decision Point |
|------|--------|----------|----------------|--------|
| 1 | Brand standard confirmation | Obtain the latest MEP standards, hold a standard alignment meeting | Brand MEP Design Criteria | Issue"Technical Deviation Application"when brand and local codes conflict |
| 2 | All-discipline data submission | Develop"Point Location Data Submission Schedule", review interior finish point location drawings | GB/T 50328 | Decide whether to adopt BIM when pipeline conflicts occur |
| 3 | Municipal conditions survey | Obtain power supply, water supply, gas, and drainage approvals | GB 50052/50015/50028 | Initiate alternative scheme assessment when municipal utilities are unavailable |
| 4 | Pipeline coordination principles | Develop"Pipeline Coordination Design Guidelines", clarify clear height control | GB 50222 | Pipeline treatment scheme for areas without suspended ceilings |
| 5 | Fire protection scheme pre-review | Hold fire protection pre-review meeting, clarify system forms | GB 50016/50116 | Decision on controversial items such as fire hose reels |
| 6 | Cost budget lock-in | Complete equipment selection list, issue quota design indicators | GB 50500 | Assessment of impact of downgrade schemes on operations |

Final word of advice: Before drawing design begins, the MEP Director must hold at least 3 "all-discipline coordination meetings" (architecture, structure, interior finish, landscape, MEP) and produce"Design Kick-off Meeting Minutes"signed and confirmed by all parties. If any party has not signed, drawing design must never start. This is experience earned through blood and tears.