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Office Renovation in Hong Kong: Cat A/B, Approvals & Timeline香港寫字樓裝修：Cat A/B、審批與時間表

Office renovation in Hong Kong hinges on the Cat A/B split and BD approval. What the landlord provides, the FS251 and WR1 approvals, and realistic fit-out timelines.香港寫字樓裝修的關鍵，在於 Cat A/B 的劃分與屋宇署（BD）審批。業主提供甚麼、FS251 與 WR1 審批，以及切合實際的裝修時間表。

The programme is set by approvals, not by the build

An office renovation (寫字樓裝修) in Hong Kong is scoped by one line in the lease, the Category A / Category B split, and paced by one constraint: BD approval. The most common way an office fit-out overruns is submitting the statutory applications after the design is frozen, when they should have run in parallel with it from day one. Understand the Cat A/B split and the approval clock, and the rest of the project falls into a predictable rhythm.

This is general guidance; confirm the specifics for your premises with the relevant departments and your landlord before you programme.

Cat A vs Cat B: know exactly what you’re inheriting

The lease divides the work between landlord and tenant:

  • Category A (landlord provides): base ceiling, main air-conditioning, the fire sprinkler network, washrooms and lift-lobby finishes.
  • Category B (tenant builds): partitions, workstations, meeting rooms, branded reception, carpet, furniture and AV.

The costly ambiguity is that “shell” and “Cat A finished” are different starting points. Confirm in writing exactly what Cat A includes, because whatever is missing falls into tenant scope and budget. This is a lease-negotiation question to settle before you sign, not a surprise to absorb mid-build.

The three statutory bodies

Three authorities usually touch an office fit-out, each with its own trigger and certificate:

BodyScopeCertificate
BDPartition and layout work usually under the Minor Works Control System; larger or structural changes need General Building Plans + an Authorised Person (AP),
FSDFire-safety provisions, means of escape, sprinkler and detection changes, exit signageFS251 on completion
EMSDNew wiring or electrical change by a registered electrical workerForm WR1, then a periodic WR2 recheck

The fire and electrical certificates gate the handover, so the fire contractor and the registered electrical worker (REW) should be booked early.

BD approval is the clock that matters

BD approval alone commonly takes 6–10 weeks, which makes it the hard constraint on the programme. The single biggest lever on your timeline is therefore to start the submission at design stage and run design development and the BD, FSD and EMSD tracks as parallel workstreams, never sequentially. If you are working within a landlord’s rent-free fitting-out period, work backwards from the deadline and submit the statutory applications on day one.

Realistic timelines

Benchmarks by size and complexity:

  • A typical 5,000 sq ft Grade-A Cat B project: ~12–16 weeks brief-to-handover, 2–3 weeks brief and concept, 4–7 weeks design development with submissions in parallel, 6–8 weeks build, 1–2 weeks snagging and move-in.
  • Small offices, 1,000–2,000 sq ft without complex submissions: can compress to 8–10 weeks.
  • Phased occupancy is possible, completing one floor and migrating teams in batches, or staging a floor zone by zone, but it adds programme time and needs noise-window scheduling.

The six-stage process

  1. Brief and measure, including a Cat A handover survey to record exactly what you are inheriting.
  2. Design development, with statutory submissions launched in parallel.
  3. Approvals in flight.
  4. Build.
  5. Snagging, the defect list closed before handover.
  6. Handover, as-built set, warranty terms and FF&E.

Keep the quote itemised

An office quote moves on finish level, the density of partitions and meeting rooms, M&E scope (AC zoning, added power, sprinkler or detection changes), AV and IT infrastructure, programme urgency and the complexity of the statutory submissions. Your protection against mid-project add-ons is itemisation, a round lump sum hides them. Confirm in writing who carries the M&E alterations, and whether the figure assumes “shell” or “Cat A finished”.

How Primeworks handles this

We start with the Cat A handover survey, so the scope you price is the scope you actually inherit, not an optimistic reading of the lease. From there we run design development and the BD, FSD and EMSD submissions as parallel tracks from day one, which is the single biggest defence against a blown programme. The quote is itemised by trade so mid-project add-ons have nowhere to hide, and the fire and electrical certificates that gate the handover are booked early rather than left to the end.

工程進度由審批決定，而非施工

香港的寫字樓裝修，其工程範圍由租約中的一行字劃定，即 Category A / Category B 的劃分，而工程節奏則受一項限制主導：屋宇署（BD）審批。寫字樓裝修最常見的超時原因，就是在設計定稿後才遞交法定申請，而這些申請其實應該由第一天起與設計同步進行。只要弄清 Cat A/B 的劃分與審批時鐘，其餘的工程便會步入可預期的節奏。

以下屬一般指引；在編排進度前，請就你單位的具體情況向相關部門及業主確認。

Cat A 對 Cat B：清楚知道你承接的是甚麼

租約把工程劃分為業主與租戶兩部分：

  • Category A（業主提供）： 基本天花、主要冷氣、消防灑水系統、洗手間及電梯大堂裝飾。
  • Category B（租戶興建）： 間隔、工作枱、會議室、品牌接待處、地毯、傢俬及影音設備。

代價高昂的含糊之處在於：「毛胚（shell）」與「Cat A 完成」是兩個不同的起點。以書面確認 Cat A 具體包含甚麼，因為凡缺少的部分都會落入租戶的工程範圍及預算。這是簽約前應該談妥的租約談判問題，而非施工中途才要吸收的意外。

三個法定機構

寫字樓裝修通常牽涉三個部門，各有其觸發條件及證明文件：

機構範圍證明文件
BD間隔及間格工程一般在**《小型工程監管制度》下進行；較大或結構性改動則需入則（General Building Plans）及認可人士（AP）**，
FSD消防安全設施，走火通道、灑水及偵測改動、出口指示完工時的 FS251
EMSD由註冊電業工程人員進行的新電線或電力改動WR1 表格，其後定期 WR2 覆檢

消防及電力證明是交場的關卡，因此消防承辦商及註冊電業工程人員（REW）應及早預約。

屋宇署審批才是關鍵的時鐘

單是屋宇署審批通常就需要 6–10 週，這使它成為工程進度上的硬性限制。因此，影響時間表最大的槓桿，就是在設計階段便開始入則，並將設計深化與 BD、FSD、EMSD 三條軌道作為平行工作流推進，而非逐項順序進行。若你在業主提供的免租裝修期內施工，應由死線倒推，並於第一天遞交法定申請。

切合實際的時間表

按規模與複雜程度的基準：

  • 一個典型的 5,000 sq ft 甲級寫字樓 Cat B 工程：由簡介到交場約 12–16 週，簡介及概念 2–3 週、設計深化 4–7 週（審批同步進行）、施工 6–8 週、執漏及遷入 1–2 週。
  • 小型辦公室，1,000–2,000 sq ft、無複雜審批：可壓縮至 8–10 週。
  • 分階段進駐是可行的，完成一層後分批遷移團隊，或將一層分區推進，但會增加工程時間，並需要編排噪音時段。

六個階段流程

  1. 簡介及量度，包括一次 Cat A 交場勘察，準確記錄你所承接的現狀。
  2. 設計深化，法定申請同步展開。
  3. 審批進行中。
  4. 施工。
  5. 執漏，交場前完成缺陷清單。
  6. 交場，竣工圖則、保養條款及 FF&E。

保持報價逐項分列

寫字樓報價受多項因素影響：裝飾等級、間隔與會議室的密度、機電範圍（冷氣分區、加裝電力、灑水或偵測改動）、影音及 IT 基礎設施、工程緊急程度，以及法定申請的複雜性。對抗工程中途加項的保障就是逐項分列，一個籠統的總額只會把它們藏起來。以書面確認由誰承擔機電改動，以及報價是以「毛胚」還是「Cat A 完成」為前提。

Primeworks 的做法

我們由 Cat A 交場勘察開始，讓你報價的範圍就是你實際承接的範圍，而非對租約過於樂觀的解讀。由此起，我們由第一天起將設計深化與 BD、FSD、EMSD 申請作為平行軌道推進，這是防止工程超時最大的防線。報價按工種逐項分列，令中途加項無所遁形；而作為交場關卡的消防及電力證明，我們及早預約，而非留到最後。

Frequently Asked Questions常見問題

What's the difference between Cat A and Cat B fit-out?Cat A 同 Cat B 裝修有咩分別？ +
Category A is what the landlord provides, base ceiling, main air-conditioning, the fire sprinkler network, washrooms and lift-lobby finishes. Category B is what the tenant builds: partitions, workstations, meeting rooms, branded reception, carpet, furniture and AV. The trap is that a 'shell' and a 'Cat A finished' unit are different starting points, and the gap falls straight into your scope and budget. Confirm in writing exactly what Cat A includes, it is a lease-negotiation question, not a construction one.Category A 是業主提供的部分，基本天花、主要冷氣、消防灑水系統、洗手間及電梯大堂裝飾。Category B 是租戶興建的部分：間隔、工作枱、會議室、品牌接待處、地毯、傢俬及影音設備。陷阱在於「毛胚（shell）」與「Cat A 完成」是兩個不同的起點，兩者的差距會直接落入你的工程範圍及預算。以書面確認 Cat A 具體包含甚麼，這是租約談判問題，而非施工問題。
How long does an office fit-out take in Hong Kong?香港寫字樓裝修要幾耐？ +
A typical 5,000 sq ft Grade-A Cat B project runs about 12–16 weeks brief-to-handover: 2–3 weeks brief and concept, 4–7 weeks design development with statutory submissions running in parallel, 6–8 weeks build, and 1–2 weeks snagging and move-in. Small offices of 1,000–2,000 sq ft without complex submissions can compress to 8–10 weeks. Crucially, BD approval alone commonly takes 6–10 weeks, so submissions must start at design stage rather than after.一個典型 5,000 平方呎的甲級寫字樓 Cat B 工程，由簡介到交場約需 12–16 週：簡介及概念 2–3 週、設計深化 4–7 週（法定審批同步進行）、施工 6–8 週、執漏及遷入 1–2 週。1,000–2,000 平方呎、無複雜審批的小型辦公室可壓縮至 8–10 週。關鍵是屋宇署審批本身通常需 6–10 週，故必須在設計階段就開始入則，而非之後。
What approvals do I need for an office renovation in Hong Kong?香港寫字樓裝修需要咩審批？ +
Three statutory bodies are usually involved. The Buildings Department (BD) handles partition and layout work, usually under the Minor Works Control System, with larger or structural changes needing General Building Plans and an Authorised Person. The Fire Services Department (FSD) covers means of escape, sprinkler and detection changes and exit signage, certified by an FS251 on completion. EMSD covers new wiring and electrical change by a registered electrical worker, certified on Form WR1 with a periodic WR2 recheck. Run all three in parallel with design from day one.通常牽涉三個法定機構。屋宇署（BD）處理間隔及間格工程，一般在《小型工程監管制度》下進行，較大或結構性改動則需入則（General Building Plans）及則師。消防處（FSD）負責走火通道、灑水及偵測改動、出口指示，完工時以 FS251 證明。機電工程署（EMSD）負責由註冊電業工程人員進行的新電線及電力改動，以 WR1 表格證明，並有定期 WR2 覆檢。三者應由第一天起與設計同步進行。

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