Pressure Treated Grandmaster Fusion with Side Shed
FREE DELIVERY — selected postcodes*  ·  10% OFF GRANDMASTER — CODE GM10
Summerhouse · GRANDMASTER · DOUBLE GLAZED · TWIN ROOM

A summerhouse and
a store in one.

The Fusion combines a full Grandmaster summerhouse with an integrated side storage shed. Double glazed as standard — two buildings, one delivery.

From £2,127£1,914

Build your Summerhouse.

Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove

Made in Britain
Selected size: None
Description

The Fusion Classic combines a full Grandmaster summerhouse with an integrated side storage shed, giving you a garden room and extra storage in one delivery. Extra tall long double doors and double glazed windows and doors are included as standard, with an extra strong double-sided roof truss for durability. Pre-assembled modular panels make it a spacious, easy-to-build twin-purpose garden building.

Key features
  • Pressure-treated 11mm tongue and groove shiplap cladding (16mm upgrade available)
  • 27x44mm panel framing, key supports doubled to 54mm
  • Integrated side storage shed
  • Extra tall long double doors
  • Double glazed windows and doors as standard
  • Side-hung opening windows as standard
  • Extra strong double-sided roof truss
  • 11mm tongue and groove roof as standard
  • Green mineral felt roof covering
  • Pre-assembled modular panels
  • All fixtures, fittings and fixings included
  • Free UK delivery on selected postcodes*
View full specifications

Free delivery to most mainland UK postcodes*
Delivery available from Sep, 2nd Wed · choose your delivery date at checkout
£4,461.00
inc. VAT

Prices as per the live configurator. Paint/trim swatch colours are indicative approximations.

Get the highlights.

Watch the showcase
Pressure-treated tongue and groove shiplap cladding. 11mm or 16mm thickness available.

Pressure-treated tongue and groove shiplap cladding. 11mm or 16mm thickness available.

For a stronger and longer lasting building with engineered interlocking cladding.

Twin room design for relaxation and storage

Twin room design for relaxation and storage

Every door and window is double glazed as standard, with a side storage room.

Extra tall 2m eaves height.

Extra tall 2m eaves height.

High eaves and ridge make the interior feel like a proper room, not a garden shed.

25-year anti-rot guarantee*

25-year anti-rot guarantee*

Pressure-treated against fungal decay and rot, painting required annually.

11mm tongue and groove apex roof.

11mm tongue and groove apex roof.

Traditional apex roof with green mineral felt as standard.

Pre-assembled modular panels for easy assembly.

Pre-assembled modular panels for easy assembly.

Flatpacked and fits through a standard UK door with all fixings included.

In the box

Everything you need, in one delivery.

No hidden extras and no surprise add-ons. Your Summerhouse arrives complete — every panel, fixing and fitting ready to go.

Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove
  • Pressure-treated 11mm tongue and groove shiplap cladding (16mm upgrade available)
  • Pre-assembled modular panels
  • Extra tall long double doors
  • Double glazed windows and doors as standard
  • Side-hung opening windows as standard
  • Integrated side storage shed
  • Extra strong double-sided roof truss
  • 27x44mm panel framing (key supports doubled to 54mm)
  • 11mm T&G roof as standard
  • Green mineral felt roof covering
  • All fixtures, fittings and fixings included
  • Free UK delivery, *on selected postcodes
Configure your Summerhouse
Why the Grandmaster Fusion

Eight reasons it's built differently.

FREE Pressure Treatment

Factory-applied before it leaves us, at no extra cost.

11 & 16mm shiplap

Upgrade from 11mm to 16mm tongue and groove shiplap for an even stronger wall.

T&G Floor and Roof

Tongue-and-groove floor and roof for a solid, tight build.

Free Double Glazing

Double glazed windows and doors included as standard.

Free Premium Fixings

Every fixing and fitting included as standard, with premium quality throughout.

25 Year Anti-rot Guarantee*

Pressure-treated against fungal decay and rot. Painting required annually.

Easy Self Assembly

Stage-by-stage illustrated instructions with all fixings included.

Free UK Day Delivery*

We offer free UK delivery on selected postcodes.

Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove
YOUR GARDEN, YOUR SPACE

Two buildings in one delivery.

The Fusion pairs a full Grandmaster summerhouse with an integrated side storage shed, one building, one footprint, one delivery. The summerhouse section is double glazed with extra tall eaves, while the storage shed gives practical garden storage alongside it.

11 & 16mm
Shiplap cladding
44mm
Double-up framing
2m
Eaves height
SHIPLAP TONGUE & GROOVE CLADDING

Tough timber, built to weather.

Every Grandmaster panel is built on 27x44mm framing with key supports doubled to 54mm, giving the building a rigidity you can feel. Pressure-treated 11mm shiplap cladding with a 16mm upgrade option, an 11mm T&G roof on heavy-duty purlins and mineral felt covering as standard, backed by a 25-year anti-rot guarantee*. Built properly and treated annually, this is a building that will give you years of enjoyment.

Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove
Built to last · Made in Britain

Engineered stronger where it counts.

27x44mm panel framing with key supports doubled to 54mm, plus an extra strong double-sided roof truss. Pressure-treated 11mm shiplap with 16mm upgrade option, green mineral felt as standard and a 25-year anti-rot guarantee*.

50+
Years' experience
UK
Designed & made
Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove
Assembly

Most of the build is already done.

Your Summerhouse arrives as pre-assembled, pre-insulated panels — designed to fit through a standard UK doorway and slot together with far fewer parts than a traditional log cabin. A quicker, simpler build, whether you do it yourself or bring in help.

Every building includes clear, step-by-step illustrated instructions. We recommend two people with basic DIY know-how — or add our assembly service at checkout and we'll handle it for you.

Add assembly at checkout
Make it yours

Configure it around how you'll use it.

Floor thickness

Floor thickness

Choose 11mm or 19mm tongue and groove floor to suit how you plan to use the building.

Wall thickness

Wall thickness

Choose 11mm tongue and groove shiplap as standard, or upgrade to 16mm for a more substantial build.

Roof covering

Roof covering

Green mineral felt as standard. Upgrade to EPDM rubber roof for longer protection.

Guttering

Guttering

Add guttering to manage rainwater runoff and protect the base of your building.

Paint colour

Paint colour

High-quality paint supplied in a tub. Apply after assembly to colour and protect the timber.

Timber base

Timber base

Optional timber base frame for use on firm, level ground if you don't have an existing concrete or paved base.

Build & price yours
Grandmaster Fusion “Classic” G1000 Summerhouse with Side Shed – 11mm Pressure Treated Tongue and Groove
SPACE, DONE PROPERLY

Your building. Done your way.

Built around how you use it, with options to make it exactly right.

Specifications

SelectSize
SelectMeasurements

Overall Dimensions

Overall Width253 cm
Overall Depth229.2 cm
Total Wall Thickness (incl. insulation)80 mm
Width (internal)229 cm
Depth (internal)174.3 cm

Eaves & Ridge

Eaves Height (inc. floor)230.7 cm
Eaves Height (excl. floor)218.2 cm
Ridge Height (inc. floor)240.2 cm
Ridge Height (excl. floor)227.7 cm
Eaves Height (internal)204.4 cm
Ridge Height (internal)212.4 cm

Doors

Door Height180 cm
Door Width73 cm
Door Opening (H × W)H180 × W73 cm

Windows

Glazing Thickness4–20–4 mm
Frame Thickness (H × W)2.7 × 4.4 cm

Floor & Base

Overall Floor Size (W × D)249 × 194.3 cm
Base Size244 × 189.3 cm

Materials

Cladding9mm LP Strongcore composite
Floor materialTongue & groove
Roof materialGalvanised steel & foam insulation
Roof coveringGalvanised steel
GlazingDouble glazing

Features

Building typeGarden room
Windows4
Roof stylePent
Cladding styleComposite board
Locking systemUPVC multi-point
U-value, metal roof0.49 W/(m²·K)
U-value, walls & floor0.31 W/(m²·K)
Pre-assembled panelsYes
Interchangeable windowsNo
Fixtures & fittingsYes

Dimensions shown for the 8 × 6; imperial values are converted from metric. 15-year anti-rot guarantee on composite — annual treatment required; terms apply.

Questions, answered.

Do I need planning permission?
Usually not. Our buildings are designed to stay under 2.5m in height and fall under "permitted development," so planning permission typically isn't required. Always check with your local authority if you're in a conservation area, national park or listed building, and note the building shouldn't be used as self-contained accommodation. We don't offer legal advice — please confirm with your local planning authority before ordering.
Do I need a base?
Yes — all garden buildings must be assembled on a solid, level foundation. Our purpose-made Eze Base provides a solid, level foundation with minimal groundwork; ask us to add it to your order. Assembling on an unsuitable foundation may invalidate your warranty.
Is it difficult to assemble?
No. The panels arrive pre-assembled and pre-insulated and fit through a standard doorway. We recommend two people with basic DIY tools, and every building comes with clear, illustrated instructions. Prefer not to build it? Add our assembly service at checkout.
How is it delivered?
Kerbside, by lorry or van. You choose a preferred delivery date at checkout and we do our best to meet it — at busier times we may need to agree an alternative date with you, and we'll keep you informed throughout. Please ensure there's clear access in front of your property on the delivery date.
★ 15-year anti-rot guarantee

Bought with confidence.

Free delivery to selected postcodes, and Made in Britain.

Customer photo
★★★★★

"Genuinely warm in winter — I work in here every day now. Build quality is excellent."

— Verified buyer
Customer photo
★★★★★

"Panels went together far faster than I expected. The composite finish looks premium."

— Verified buyer
Customer photo
★★★★★

"From order to install was seamless. The team kept me informed the whole way."

— Verified buyer

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