How Much Does a Home Annex Cost in Jeddah?
Building an annex is the fastest way to add living space, an office or a guest room without moving or expanding horizontally. But cost differs sharply between a sandwich panel annex and a conventional one. This guide compares both honestly and details the cost items people usually forget.
Most requested annex types
- Rooftop annexes: the most common in Jeddah, using otherwise wasted space.
- Garden annexes: ideal as a majlis or standalone office.
- Annexes with bathroom and kitchen: need plumbing and add 15% – 25% to cost.
- Portable prefab annexes: built off-site and installed within days.
Sandwich panel vs conventional construction
| Item | Sandwich panel | Conventional |
|---|---|---|
| Cost per m² (basic finish) | SAR 700 – 1,200 | SAR 1,400 – 2,200 |
| Build time | 2 – 4 weeks | 2 – 4 months |
| Load on the roof | Very light | Heavy, needs structural study |
| Thermal insulation | Built in | Requires separate layer |
| Can be dismantled and moved | Yes | No |
| Expected lifespan | 15 – 25 years | 40+ years |
Cost items people forget
- Slab or base preparation.
- Electrical installation and distribution board.
- Plumbing and drainage if a bathroom is included.
- Air conditioning and ventilation.
- Quality doors and windows.
- Interior finishing: gypsum, paint, flooring.
- Lifting materials to the roof for upper-level annexes.
Indicative examples by size
Figures are indicative and vary with finish level, location and access.
- 4×5 m (20 m²) without bathroom: SAR 15,000 – 24,000.
- 5×7 m (35 m²) with bathroom: SAR 30,000 – 48,000.
- 6×10 m (60 m²) with kitchen and bathroom: SAR 55,000 – 85,000.
Permits and requirements
Before starting, confirm municipal requirements for rooftop construction and permitted build ratios, and verify the roof can carry the additional load.
Lightweight annexes are usually easier structurally, but that does not remove the need for regulatory checks.
Tips before you build
- Define the use precisely before design — a bedroom differs from an office or storage.
- Ask for an itemised quote, not a single lump sum.
- Agree the build duration in writing, with a delay clause if relevant.
- Plan electrical and AC routes before closing walls, not after.
Note: prices in this article are indicative and vary with specification, quantity and site conditions. For an exact figure for your project, request a free quote.
Frequently asked questions
Does a rooftop annex need roof strengthening?+
Panel annexes are lightweight and usually need no strengthening on a sound roof, but a technical inspection is always advised, especially on older buildings.
How long does a panel annex take?+
Two to four weeks depending on size and finish, versus two to four months for conventional construction.
Can the annex be relocated later?+
Yes — one of the main advantages of sandwich panels is that they can be dismantled, moved and reinstalled with limited material loss.
