What Does Shed Assembly Actually Cost?

A flat-pack shed in boxes isn't the same as a shed in your garden. Here's what assembly actually costs.

Quick Price Guide

Shed Size	Assembly Only	Assembly + Felt	With Base
4x3 / 5x3	£80-£120	£100-£150	+£150-£250
6x4	£120-£180	£150-£220	+£200-£300
8x6	£180-£280	£220-£350	+£300-£450
10x8+	£280-£400	£350-£500	+£450-£650

Exeter area prices, 2025. Assembly assumes existing level base.

---

What's Included in Assembly

Basic Assembly

• Unpacking and checking all parts
• Building floor frame
• Attaching floor boards
• Erecting walls
• Fitting roof panels
• Hanging door(s)
• Fitting any windows
• Basic checks everything's square and secure

Not Usually Included

• Roof felt (often separate charge or DIY)
• Base preparation
• Treatment/painting
• Shelving and internal fittings
• Electrics

---

The Base Question

No base = no shed assembly.

A shed must go on a level, solid surface. Without this, the shed will warp, rot, and fail.

Base Options

Paving slabs:

• Laid on sand, levelled
• DIY-able but time-consuming
• Cost: £15-£25 per m² DIY, £40-£60 per m² installed

Concrete slab:

• Most solid option
• Needs excavation, formwork, mixing
• Cost: £50-£80 per m² installed

Timber frame base:

• Pressure treated bearers on blocks
• Quicker than concrete
• Cost: £30-£50 per m² materials + labour

Plastic grid base:

• QuickJack or similar systems
• Fast to install
• Cost: £25-£40 per m² + labour

Base Preparation Time

Add 2-8 hours depending on method and ground conditions. This is separate from assembly.

---

Factors Affecting Price

Shed Quality

Budget sheds (overlap, thin boards):

• Quicker to build (simpler design)
• Flimsier = more fiddly to align
• Some are surprisingly time-consuming due to poor quality

Mid-range (tongue & groove, thicker):

• More substantial
• Better engineered = easier to assemble
• Worth the extra cost usually

Premium (thick walls, workshop quality):

• Heavy panels
• May need two people throughout
• Higher assembly cost but better shed

Shed Size

Bigger = more panels = more time. But it's not linear - a shed twice the size doesn't take twice as long.

Access

Good access: Direct from driveway/path Poor access: Through house, up steps, over lawn, round corners

Poor access adds significant time carrying heavy panels.

Ground Conditions

Level, ready base: Standard pricing Sloping ground: May need frame adjustment or more complex base Soft ground: May need additional support

---

DIY vs Professional

DIY Assembly

Pros:

• Save £100-£300
• Satisfaction of doing it yourself
• No scheduling constraints

Cons:

• Takes much longer (full day typically)
• Risk of mistakes
• Heavy panels need helpers
• Tools required

Time: 4-8 hours for typical 6x4, longer for bigger

Professional Assembly

Pros:

• Done in a few hours
• Experience means fewer mistakes
• Includes handling heavy panels
• Proper tools and techniques

Cons:

• Cost
• Scheduling

---

The Felt Question

Shed roof felt is essential but often done badly.

Felt Options

Standard mineral felt: Cheap, lasts 3-5 years Torch-on felt: Better, lasts 10+ years (harder to DIY) Shingles: Longer lasting, more expensive

Felting Cost

Add £30-£100 depending on shed size and felt type.

DIY Felting Tips

• Warm day (felt is easier to work)
• Start from bottom, overlap upwards
• Use enough clout nails
• Seal edges properly

---

Typical Complete Job

Example: 8x6 shed

Item	Cost
Shed (typical mid-range)	£400-£600
Base (timber frame)	£150-£250
Assembly	£180-£280
Felt	£50-£80
Treatment	£40-£60
Total	£820-£1,270

Compare with "£450 shed" advertised - the true installed cost is always higher.

---

Treatment Options

Factory Treated

Some sheds come pre-treated. Check what's included - some "treatments" are just temporary preservative for transit.

DIY Treatment

• Treatment fluid: £20-£40
• Brush or sprayer
• Time: 2-3 hours

Professional Treatment

Usually £40-£80 including treatment cost. Worth adding to assembly visit.

---

Installation Process

Before I Arrive

• Base ready and level
• Clear access route
• Shed delivered and checked for damage
• Ideal: opened and parts laid out

The Build

Small shed (4x3, 5x3): 2-3 hours Medium (6x4, 8x6): 3-5 hours Large (10x8+): 5-8 hours

After Assembly

• Walk-through showing features
• Check door/window operation
• Discuss treatment/maintenance
• Collect packaging (or leave for you)

---

Common Issues

Missing Parts

Happens more than you'd think. We check before starting. If something's missing, manufacturer needs to supply.

Quality Problems

Budget sheds sometimes have:

• Warped panels
• Pre-drilled holes that don't align
• Split boards

We work with what's there, but there are limits.

Unlevel Base

Can't magic a level shed from an unlevel base. This needs fixing first.

---

Need a shed assembled? I build sheds across Exeter - with or without base preparation. Call 01392 964094 or get a quote.